Junkfood Science: July 2008

July 31, 2008

The exercise diet that wasn’t

“Step it up ladies,” we’ve been hearing this week. Research from the University of Pittsburg was reported as showing that it takes an hour a day of exercise for overweight women to get in shape and keep the weight off. According to the media, a new study published in Archives of Internal Medicine found “it only takes one hour of exercise a day to maintain a steady weight loss and keep those unwanted extra pounds off.”

Did reporters read the same study I did? Or, did they take their lead from a press release and fill in the rest with what’s popularly believed fat women should do?

The objective of this study, led by John M. Jakicic, Ph.D., associate professor and Director of the Physical Activity and Weight Management Research Center at the University of Pittsburgh, was to answer the debate about “the amount of physical activity that will facilitate weight loss maintenance.”

It found that no amount or intensity of exercise worked to maintain weight loss. Instead, it demonstrated that exercise was mostly unrelated to weight loss and that cutting calories will result in a temporary weight loss for about 6 months and then, even with continued caloric restrictions and exercise, the inevitable and expected weight gain trajectory ensues.

The study’s actual findings are considerably different from what we’ve been hearing in the news, but won’t be at all surprising to JFS readers or obesity experts, as they’re nearly identical to nearly every other weight loss study published over the past half century. Let’s take a look.


Overview

This two-year intervention trial had recruited 201 physically and psychologically healthy women, with an average age of 37 years and body mass index of 32.6. This registered trial [ID # NCT00006315] ran from December 1, 1999 to January 31, 2003. The interim results after the first year had been published in 2003 in the Journal of the American Medical Association and this paper is reporting the final results.

The women participants had been randomly assigned to one of four exercise groups — combinations of intensity and durations: Vigorous intensity/High duration (VH), Vigorous intensity/Moderate duration (VM), Moderate intensity/High duration (MH); and Moderate/Moderate (MM) — to burn an estimated 1,000 to 2,000 kcal/week. They’d been taught the prescribed exercise regimens and to monitor their pulse to reach their age-predicted maximal heart rates, and provided with home treadmills.

The weight loss program also included fat-restricted, very low-calorie diets aiming for between 1,200 and 1,500 kcal/day, which the researchers monitored using food frequency questionnaires; group meetings (weekly x 6 months; bimonthly x 6 months; and monthly x 6 months); telephone calls one to two times per month; and questionnaires to assess other leisure-time physical activity.

Nearly 85% of the women (170) completed the two-year weight loss study. The authors reported only the results of those who completed the study. [In other words, they didn’t skew the results by including those who dropped out and carry forward their weight losses.] Compliance with the group meetings and phone follow-ups was similar among all of the intervention groups: nearly 80% during the first six months and over the course of the study dropped to 67%.


Findings

Over the first six months, all of the groups lost weight, 8.3% to 10.8% of their body weight. There was no statistical difference in weight losses among the various exercise groups, however, and the average weight losses differed by a mere 4.84 pounds. The groups exercising the longest (regardless of intensity) lost slightly more than those exercising for half as long each week.

But wait: before you conclude that the nominal larger weight losses were because of exercise, the groups differed in their caloric intakes (1,454 to 1,551 kcal/day). Those women had also cut their average daily calories by about 97 kcal/day more than the other groups. If you believe that 3,500 kcal = 1 pound, this calorie reduction alone would account for a 5-pound weight loss. Nearly exactly the difference seen.

Thereafter, every intervention group steadily gained weight and the upward trajectories showed no signs of leveling off when the trial was stopped at the end of two years. Does this look like weight maintenance to you?

Like all weight loss studies, the familiar rebounding wasn’t because the women were pigging out and cheating on their diets. They all continued to restrict their calories to 1,454-1,689 kcal/day through the end of the trial — eating 350 to 642 kcal less per day than they had been eating while weight stable before the start of the trial. While all of the groups slipped in their exercise regimens over the two years, they also continued to exercise considerably more (about 2-5 times) than they had been at the start of the study.

If you believe the calorie theory, just considering the continued calorie restrictions, then there should have been humongous total weight losses and a dramatic difference of 60 pounds of weight lost between the groups at the end of two years.

Instead, after two years of dieting and exercise, not only were all of the women gaining weight (already nearly half of their weight loss back), but the average weight losses differed among the different regimens by less than 1 ounce per week: 6.38 pounds total at the two year mark. This, too, was not statistically significant, nor was the difference in regain trajectory patterns clinically meaningful.

In other words, weight loss was no more successful with more or less exercise. There was no statistical difference.

And again, in a secondary analysis, those “most successful losers” on the lower end of the rebound trajectories after two years, were also the women most cutting their calories - to increasingly extreme levels, down to 1,365 kcal/day, as well as exercising nearly 6 hours a week. Their calorie restrictions alone during those final 18 months, based on 3,500 kcal = 1 pound, theoretically would have resulted in the loss of another 95 pounds (1.3 pounds/week). But, of course, they were still gaining.

Once again, as the body of evidence has continued to show, regardless of the contrivance to cut calories, most everyone will lose a degree of weight temporarily, then homeostatic metabolic adjustments kick in to return body weights to their genetically-determined setpoint range. [Nor is there any support for healthfulness of starvation-level diets and extreme measures used by anorectics to a maintain weights appreciably lower than what is natural for them.]

Even the most rigidly-followed diets among the most motivated people in the real world will result in weight loss for about 6 months and then regain. It’s only the rate and trajectory of the regains that vary, not the fact of regain. As the FTC’s expert panel and every expert review of the evidence has concluded, weight regain is the rule and virtually everyone regains all of their weight by 5 years. While it is well acknowledged among obesity researchers that for a diet study to credibly demonstrate effectiveness or evaluate health outcomes, it must follow people for at least five years until weights have stabilized, this is another one that stopped well before that.

How many more decades of these studies will there need to be before people realize that weight loss interventions don’t work? While people can repeatedly lose and gain a small percentage of their weight, most yo-yoing a dozen or so pounds, the natural diversities of our sizes are not determined by calories in and calories out.

As professor and Jakicic and colleagues noted in their concluding comments:

Analysis based on randomized group assignment did not indicate a favorable contribution of exercise to weight loss maintenance... However, the greater magnitude of weight loss achieved in the present study may be a result of a greater emphasis on reduction in energy intake along with the inclusion of physical activity... This study demonstrates the difficulty in sustaining weight loss of 10% or more of initial body weight...

However, relatively high levels of physical activity appear to contribute to sustained weight loss.

The study’s conclusion — that exercising 275 minutes/week is beneficial for weight loss, and that “interventions to facilitate this level of physical activity are needed” — are a disconnect, given what the evidence actually showed. Yet this study is precisely what the evidence looks like behind the government’s 2005 Dietary Guidelines calling for an hour exercise a day for weight management.

In fact, according to Dr. Jakicic’s university webpage, his line of prior research showing “that approximately 60 minutes a day of moderate intensity is necessary to enhance long-term weight loss and prevent weight regain...has significantly influenced the physical recommendations included in the 2005 Dietary Guidelines for Americans, which supports this level of physical activity for weight control.”

But how many people actually read the research behind guidelines? Or, has everyone chosen to believe that government public health guidelines are based on something like... evidence?

© 2008 Sandy Szwarc. All rights reserved.


Disclosures

No media story reported the financial disclosure, although it was noted in both the journal article and press release: “Dr. Jakicic is on the Scientific Advisory Board for BodyMedia Inc. and the Calorie Control Council.” BodyMedia makes wearable body monitoring devices that, according to its website:

Our innovative products and patented technologies provide accurate and actionable information about the health and behaviors of people outside of the traditional clinical setting... all taking a more proactive role...through the tracking and management of day-to-day behavior modification...

As the urgency of global health issues such as obesity, diabetes, and cardiovascular disease continues to grow...BodyMedia is responding to these trends and problems by creating state-of-the-art solutions that make it easy for patients and practitioners to track a person's total energy expenditure, duration of physical activity, nutrition, and sleep.


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July 30, 2008

Family home visits

The idea is inconceivable that government agents would come into homes to evaluate if parents are feeding and caring for their children properly; screen children and family situations to identify parenting practices, children’s weights or social-emotional development that fall short of state-approved standards; and report those children and parents for case management and treatment. For Americans who don’t follow legislation and public health policies, even talk of such programs might be considered conspiracy theories. Last year, two Acts were introduced into the U.S. House of Representatives that would grant the federal government unprecedented control over parenting and implement state home visits, targeting military families and poor families first. This week, these Acts were scheduled for debate.

Dr. Karen Effrem, M.D., is a pediatrician and researcher who has been following legislation that affects parental rights and the health of children. She wrote an article this week describing the lack of scientific validity and efficacy, costs, dangers and implications for parents, children and healthcare provider of the proposals in these pieces of legislations. This issue has little to do with politics but more the cautionary insights it offers about even well-meaning public health programs.

Summaries of the legislation sound good at first glance, until you dig into the fine print:

H.R. 3289: PRE-K Act addresses state preschool programs and puts the federal government in charge of what children learn and implements services to support healthy child development.

H.R. 2343: Education Begins at Home Act directs the Secretary of Health and Human Services to fund a State early childhood home visitation program and the Secretary of Defense to fund early home visitations for military families. It also revises Early Head Start programs and adds services to conduct home-based interventions and inform new parents of proper care for infants and children under five.

Dr. Effrem has read the fine print. In her article for Education News, as well as her statement to the Subcommittee on Education Reform, she raised a number of concerns:

These bills put the government in control as both parent and educator for children from birth to age 5. Both focus on poor families who have the least wherewithal to resist this government intrusion, but they also extend to military families. The home visiting bill calls for developmental screening, which includes mental screening, and the Pre-K Act promotes mental screening of all the children and their families in these programs. And of course, parental consent, choice, and control are never mentioned for any aspect of these bills.

These programs focus on “socioemotional screening, which is mental screening,” she said. “Mental health screening is very subjective no matter what age you do it. Obviously it is incredibly subjective when we are talking about very young children.”

The Pre-K Act calls for mental screening of all the children and their families enrolled in these programs and parental consent is never mentioned, she said. But, despite claims of effectiveness, she wrote:

[E]arly childhood programs are not effective and several studies have shown evidence of academic and or emotional harm.” For instance, illiteracy rates have actually increased in New Jersey where preschool for poor children was court ordered. And, data from several national studies and surveys performed by the federal government have shown very significant increases in defiant, disobedient, and aggressive behavior, as well as impaired social skills in children who are attend preschool and child care compared to children raised at home...

Now, as is happening in Minnesota and states around the nation, these subjective screening results are going into children's records, falsely labeling them as academically, socially, or mentally defective even before they begin their academic careers. This has the potential of affecting college, military service and employment and expanding the rolls of the overburdened special education system and government control in the schools.

Moreover, she sees these programs as not helping children, but using subjective behavior or emotional measures to identify children who can be given “the myriad harmful and ineffective psychotropic drugs that are being prescribed to children at alarmingly younger ages.” These mental health screening tests have been shown to incorrectly label large numbers of children and have been shown to have high false positives, she said.

One commonly used screening instrument has a 73% false positive rating, meaning that for every 27 children supposedly correctly identified as having an emotional problem on this screening test that follow admittedly "subjective" criteria that are "value judgments based on culture" according to the Surgeon General, other families are falsely told that something is wrong with their child and referred for further evaluation and treatment which more and more commonly involves ineffective and sometimes lethally dangerous drugs.

She referenced a Boston Globe letter from Dr. Daniel Fisher, a psychiatrists who has evaluated children in schools, who wrote: “These quick-fix screening tests invariably end up with quick fixes of kids by labeling them and placing them on medication, without a comprehensive psychosocial evaluation and assistance to the children and their interpersonal environment...I know that myriad factors can cause what appear to be symptoms of mental illness.”

In her statement to legislators, Dr. Effrem reviewed the research on the effectiveness of cognitive, language, social and emotional health screenings and intervention programs in young children.

· There are no recognized signs and symptoms of abnormal mental health in children because the very same indications are also often characteristic of normal development, according to the WHO 2001 World Health Report and the 1999 report of the Surgeon General.

· Dr. Benedetto Vitiello, director of Child and Adolescent Treatment and Preventive Interventions Research Branch for the National Institutes of Mental Health, admitted that “the diagnostic uncertainty surrounding most manifestations of psychopathology in early childhood” and that little research has been conducted on the effectiveness of interventions in young children. More importantly, “the long-term risk-benefit ratio of psychosocial and pharmacologic treatments is basically unknown.”

· According to a 2005 National Center for Infant and Early Childhood Health Policy report, “diagnostic classifications for infancy are still being developed and validated” and there was a “lack of longitudinal outcome studies.”

She goes on to describe the research on other home visit intervention programs that have been tried, such as the Nurse Family Partnership, which showed few, if any, statistically significant effects on child socioemotional development or behavior. Another national home visit program, begun with the goal of reducing child abuse, also failed to show evidence of success in significantly impacting child abuse rates or risks. And finally, she reviewed the body of international evidence on Head Start programs, which surprisingly and consistently “continue to show that improvements in academic performance are not sustained much beyond the third or fourth grade.”

While the available evidence for effectiveness of the proposals in these two pieces of legislation are lacking, moving forward without considering the adverse effects on children and families was especially disturbing. Many of the concerns and weaknesses are very similar to those seen in child and teen suicide prevention screening programs, covered here.

As she told World Net Daily: “There are privacy concerns because when home visitors come into the home they assess everything about the family: Their financial situation, social situation, parenting practices, everything. All of that is put into a database.” Reporter Chelsea Schilling went on to write:

Effrem said it does not specify whether parents are allowed to decline evaluations, drugs or treatment for their children once they are diagnosed with developmental or medical conditions. “How free is someone who has been tagged as needing this program in the case of home visiting — like a military family or a poor family?” she asked. “How free are they to refuse? Even their refusal will be documented somewhere. There are plenty of instances where families have felt they can't refuse because they would lose benefits, be accused of not being good parents or potentially have their children taken away.”

When WND asked Effrem how long state-diagnosed conditions would remain in a child's permanent medical history, she responded: “Forever. As far as I know, there isn't any statute of limitations. The child's record follows them through school and potentially college, employment and military service.”

Effrem said conflicts could also arise when parents do not agree with parenting standards of government home visitors.

Even when parents voluntarily enroll their children in government preschool, they have no say over the curriculum, said Dr. Effrem. “There's plenty of evidence of preschool curriculum that deals with issues that have nothing to do with a child's academic development...things that don't amount to a hill of beans as far as a child learning how to read.” (As we’ve seen, those include things like compulsory “nutritional assessments” to identify overweight toddlers and preschoolers, and mandated teaching them ‘healthy eating’ (defined as restricting sugars, calories and fats) and exercise to eradicate obesity. This is also the same early preschool program that this legislation would equip with home visit monitoring.)

When government programs promise to know better than parents how to take care of their children, taking a careful look might most help kids. That proverbial slippery slope feels increasingly steep.


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July 29, 2008

Does banning hotdogs and bacon make sense?

Which of these sources will give you the most ingested nitrites:

467 servings of hotdogs

1 serving arugula

2 servings butterhead lettuce

4 servings celery or beets

your spit

The answer is obvious ... or is it?

How often do we hear advice to avoid processed meats — like hotdogs, bacon, ham and sausages — because they contain nitrates that have been linked to cancer? There is no safe amount of processed meats, the project director for the World Cancer Research Fund report told Dr. Albert Lim Kok Hooi of The Star this month. [Dr. Hooi’s article also claimed, ostensibly based on that WCRF report, that two-thirds of all cancers could be prevented if we were all thin, ate right and didn’t smoke. It advocated plaques at the entrance of all restaurants, school and office cafeterias warning: “Obesity causes cancer!”]

A campaign* to even ban hot dogs and other processed meats from school cafeterias in Austin, Texas, has also been in the news this month, with a local registered dietitian claiming that a single hotdog each day could increase colorectal cancer by 21%.

Since this is the last week of National Hotdog Month — and American Beer Month and National Ice Cream Month, for the full summertime meal deal — and a major international scientific safety report was recently published on nitrates in foods, which received very little media coverage, let’s look at this popular food concern.

As is nearly always the case, food fears are short on science and tall on misinformation. Many may remember that scare from the 1970s, claiming that nitrates could be carcinogenic, based on a report said to have found lymphatic cancer in 13 rats. Few consumers heard the rest of the story: that the preliminary MIT research behind that scare had had no peer review prior being acted on by the FDA and USDA, and was later discredited as faulty when an interagency working group of scientists from the FDA, USDA and NIH was convened to review the scientific data. The study was also sent to outside reviewers. As a 1983 risk assessment from the National Research Council noted, normal FDA review procedures hadn’t been followed during that scare, in what had seemed justifiable at the time to protect public health and in response to consumer group petitions; but “normal peer review would have revealed the fatal flaws in the MIT data.”

In 1981, the National Academy of Sciences reviewed the scientific literature and found no link between nitrates or nitrites and human cancers, or evidence to even suggest that they’re carcinogenic. Since then, more than 50 studies and multiple international scientific bodies have investigated a possible link between nitrates and cancers and mortality in humans and found no association.

What may be more surprising to learn is that scientific evidence has been building for years that nitrates are actually good for us, that nitrite is produced by our own body in greater amounts than is eaten in food, and that it has a number of essential biological functions, including in healthy immune and cardiovascular systems. Nitrite is appearing so beneficial, it’s even being studied as potential treatments for health problems such as high blood pressure, heart attacks, sickle cell disease and circulatory problems.


Brief history

Preserving meats using various salts has been practiced for thousands of years, even Homer’s era of 850 B.C. Salt works to kill aerobic bacteria, such as salmonella and E.coli on surfaces. But inside meats that are age-cured, the anaerobic environment enables Clostridium botulinum spores to thrive. Since around the Middle Ages, saltpetre (potassium nitrate) was used in curing meats, added both for distinct flavor and to preserve meat’s color, but it also blocks the growth of botulism and prevents spoilage and rancidity. The earliest printed cookbooks from the early 1700s show it used in astounding amounts, up to 50 times levels of nitrates and nitrites in more modern recipes. Even my old copy of Mrs. Beeton’s Book of Household Management by Mrs. Isabella Beeton, published in 1859, called for liberal amounts of salt and saltpetre.

TO CURE BACON IN THE WILTSHIRE WAY.

805. INGREDIENTS - 1–1/2 lb. of coarse sugar, 1–1/2 lb. of bay-salt, 6 oz. of saltpetre, 1 lb. of common salt.

Mode.—Sprinkle each flitch with salt, and let the blood drain off for 24 hours; then pound and mix the above ingredients well together and rub it well into the meat, which should be turned every day for a month; then hang it to dry, and afterwards smoke it for 10 days.

Time.—To remain in the pickle 1 month, to be smoked 10 days.

Sufficient.—The above quantity of salt for 1 pig.

Around the turn of the century, chemists realized that the active ingredient in saltpetre was the nitrite and this enabled sodium nitrite, in much smaller quantities, to replace saltpetre. This also greatly reduced the saltiness of the cured meats, which had to be soaked in water to be palatable. Nitrite levels in frankfurters were noted to be as high as 1,400 ppm before that change. Since 1925, when sodium nitrite was shown safe for humans, it has been approved for use in cured meats in the United States, and no cases of botulism have been associated with commercially cured meats since then. You’ll find being sold curing salts of sodium nitrate and nitrite (i.e. Morton’s Tender Quick) and Prague powders (#1 of 5.25% sodium nitrite and salt for cooked meats like lunch meats, hotdogs, hams and sausages; or #2 of 6.25% sodium nitrite and 4% sodium nitrate and salt traditionally used for longer dry-cured meats like uncooked bacon and salami).

Since 1974, the use of potassium nitrate and even sodium nitrate has been barred in commercially cured meats like hotdogs and pumped bacon by the USDA, as a precautionary reaction to that earlier scare; and only scant amounts of sodium nitrite are allowed since 1978, a mere 120 parts per million. But during the curing process, most of this nitrite forms nitric oxide, which binds to iron keeping the meat’s color pink, and the amount of nitrite remaining in the cured meats we eat has been shown to be only about 10 parts per million.


Sources of nitrates and nitrites

Nitrate, from any dietary source, does not accumulate in our body. Nor does nitrite.

Nitrite is formed in especially high amounts in our mouths from bacteria. Salivary nitrite accounts for 70-97% of our total nitrite exposure. Ingested nitrate (from foods and water) is converted to nitrite when it comes into contact with the bacteria in our saliva. About 25% of the nitrate we eat is converted to salivary nitrate, and up to 20% is converted to nitrite. Most absorbed nitrate is simply excreted in the urine within five hours.

In our stomach, nitrite then reacts to the natural flora and gastric contents, yielding nitric oxide, and little is absorbed. Moreover, what nitrite that is absorbed disappears quickly from our bloodstream, with the average half-life estimated to be as low as 1-5 minutes. More recently, the favorable role of nitrite and the formation of this nitric oxide in our bodies is beginning to be better understood (see below).

Nitrate undergoes a number of metabolic interconversions, absorbed in the proximal intestine and becoming part of the enterosalivary circulation, and is recirculated in the blood, recycled between the saliva and the gut. In other words, total nitrate and nitrite in our blood is almost identical to the nitrate levels, according to the scientific opinion issued by the European Food Safety Authority (EFSA), adopted on April 10, 2008.

The primary source of nitrites in our diets is vegetables, and to a lesser degree water and other foods. While it’s popularly believed that nitrates and nitrites mostly come from processed meats, they’re actually a very small source of our nitrite intakes, less than 5-10%. And nitrates aren’t present at all in commercially processed meats.

Nitrates occur naturally in vegetables and plants as a result of the nitrogen cycle where nitrogen is fixed by bacteria. Dietary studies around the world have found 70% (in UK) to over 97% (New Zealand) of human consumption of nitrates and nitrites comes from vegetables alone, regardless of organic or conventionally grown. On average, about 93% of the nitrites we get each day comes from the nitrates in vegetables.

So, to see how much nitrate people are eating and if people could be consuming too many vegetables and exceeding recommended daily intakes for nitrates, the Scientific Panel on Contaminants in the Food Chain of the EFSA by the European Commission just published its report on Nitrates in Vegetables in the June issue of EFSA Journal. They compiled 41,969 analytical results from 20 member states and Norway examining the nitrate levels in produce. Nearly every vegetable tested contained measurable amounts of nitrates, with averages varying from 1 to 4,800 ppm. For example, average levels were:

arugula 4,677 ppm

basil 2,292 ppm

butterhead lettuce 2,026 ppm

beets 1,279 ppm

celery 1,103 ppm

spinach 1,066 ppm

pumpkin 874 ppm

This compares to standard hotdogs or processed meats with average nitrite levels of 10 ppm.

By definition, cured meats must include the salts, sodium nitrite or sodium nitrate, so what about those expensive “nitrate-free” hotdogs and cured meats being sold to chemical-anxious consumers? They use “natural” sources of the very same chemical, such as celery and beet juice and sea salt. A chemical is still the same chemical, regardless of where it comes from. NO3 = NO3. They are no more free from nitrates and nitrites than conventional hotdogs.

So, when someone says that they avoid all foods with nitrates and nitrites (or that we should), they missed basic chemistry class.

The scientific expert panel went on to estimate how much nitrate people typically ingest, based on eating 400 grams (just under a pound, 14 ounces) of a variety of vegetables, along with water and 35-44 mg from cured meats a day. They calculated that the average person might eat as much as 157 mg nitrates a day. This is well within the Acceptable Daily Intake for nitrate, which is 3.7 mg/kg body weight/day (equivalent to 222 mg nitrate per day for a 60 kg adult) established by the former Scientific Committee on Food and confirmed by the Joint FAO/WHO Expert Committee on Food Additives in 2002.

The EFSA scientific panel noted that most people would actually consume less nitrate, as we usually eat half of our daily produce as fruits which have low nitrate levels; and processing (washing, peeling and cooking) would reduce levels more. This concurs with other estimates of nitrite and nitrate consumptions in the U.S. of 100 mg per day per person, according to the National Toxicology Program. The EFSA panel also noted that a small part of the population in some regions of the world eat only leafy vegetables which have especially high amounts, and could lead to the ADI being exceeded. But, there are no epidemiological studies to “suggest that nitrates from diet or drinking water is associated with increased cancer risk,” they wrote. Despite being the major source of nitrates, vegetables are considered part of a healthful diet and there’s no evidence to suggest vegetarians have higher risks for cancers, either. [Researchers have been suggesting since 1990 that the ADI be raised, but it hasn’t.]

The scientific panel’s review of the evidence found that the few studies suggesting a link between nitrates and cancers were of weak designs with “often very weak or even null” associations. The strongest studies and the body of evidence continue to find no increased risks.


Safety concerns

The safety of nitrates and nitrites in our foods and water has been taken quite seriously, and you could devote months to reading the hundreds of studies that have been done over recent decades examining potential health risks. The toxicology of nitrates and nitrites has been reviewed by numerous expert bodies, according to IPCS INCHEM, of the International Programme on Chemical Safety and the Canadian Centre for Occupational Health and Safety, which compiles international peer-reviewed chemical safety publications and database records from international bodies for public access.

The main toxic effect, although reversible, is methaemoglobinaemia. This is a rare condition when hemoglobin is oxidized to methemoglobin and becomes unable to transport oxygen to the tissues. Symptoms don’t become apparent until concentrations of methemoglobin reach 20% and can be fatal at very high concentrations (>50%), but is readily treated.

The levels of nitrites and nitrates said to be toxic are all over the place, as criteria for toxicity vary. But in general, toxic doses in the literature range from 2,000 to 4,000 mg for nitrate and 60 to 500 mg for nitrite. We're talking extremely high levels, far beyond what we would normally get in our diet without accidental poisonings or contamination. Studies on sodium nitrite even at doses of 30-300 mg as a medication for vasodilation or as an antidote in cyanide poisoning, for example, caused no toxic effects, according to the National Academies of Science.

Dr. G.J.A. Speijers at the Laboratory for Toxicology, National Institute of Public Health and Environmental Protection at Bilthoven, Netherlands, for example, described three patients with methaemoglobinaemia who had accidentally eaten meat with toxic levels of nitrites (10,000 to 15,000 ppm). Another case of methaemoglobinaemia was caused by accidental ingestion of 700 mg of sodium nitrite in water. Babies under 3 months of age, and people with certain hereditary enzyme deficiencies, certain medical diseases with lower gastric acids, and possibly the elderly may be at higher risks for methaemoglobinaemia and toxicity, several reviews have suggested.

So, how much is believed to be safe?

As with all toxicology and governmental health recommendations, remember that “safe” levels are not measures of safety, but of safety margins. So the ADI, as defined by the FDA, Joint FAO/WHO Expert Committee on Food Additives, and the European Commission’s Scientific Committee on Food, first took the NOEL level — the level where animal tests have shown no observable adverse effect over a lifetime of exposure — and then added a 100-fold safety margin to arrive at the most conservative level for human exposure.

So, while the NOEL for sodium nitrite has been reported in research at between 5-100 mg/kg/day, the ADI is less than 0.1 mg/kg/day. There’s a very wide safety margin.

Of course, any chemical, even ordinary salt, can be lethal at toxic doses. While the lethal doses of nitrite reported in the literature vary from 1,600 to 9,500 mg, the lethal dose of sodium nitrite, as per those Material Safety Data Sheets, is estimated at 1,000 to 2,000 mg.

This would equate to eating 2,222 to 4,444 hot dogs in a single meal. Even Joey Chestnut couldn’t do that!


Cancer strikes the greatest fear

Despite what’s still popularly believed, there is no evidence that nitrate or nitrite cause cancers in animals. And there is no evidence to indicate that nitrite or nitrate ingestion is carcinogenic in humans, either. Numerous international studies have attempted, unsuccessfully, to find any consistent or causative links between cancers or congenital malformations and nitrates or nitrites in food and water. “The majority of the studies revealed no correlation, or in some cases a negative correlation,” according to Dr. Speijers.

The 1981 scientific report from the National Academy of Science also concluded that there was no evidence to suggest that nitrates or nitrites cause cancer or are mutagenic. The National Toxicology Program, a division of the U.S. Department of Health and Human Services and considered the leading authority in the world on the safety of chemicals, conducted multi-year analyses at the request of the FDA. Its May 2000 and May 2001 reports “Toxicology and Carcinogenesis Studies of Sodium Nitrite,” also found “no evidence of carcinogenic activity” due to sodium nitrite. Sodium nitrite does not cause cancer in laboratory animals, these experts concluded, even when the animals are given massive doses in their water throughout their lifetimes. Also reported in the Carcinogenic Potency Database, research to date has found no link between nitrites and cancer.

While there remains no evidence for nitrite or nitrate carcinogencity, according to the National Research Council, the confusion among consumers may come from hearing cancer concerns raised about nitrosamines. As the IPCS-INCHEM notes, the sole cancer suspicion lies in the formation of N-nitroso compounds (NOCs), whether in the stomach or within the food itself, which have been shown carcinogenic in animals when exposed to high levels. Whether these compounds form in humans in normal dietary conditions in large enough amounts to pose a health risk, however, has not been established. In fact, as it turns out, the pH of our gastric juices doesn’t support nitrosamine formation and there are other substances in our body that inhibit their formation, too.

Nitrites and nitrates can combine with natural amines from proteins to form various NOCs. But the concentrations of nitrosamines in bacon and cured meat are at undetectable levels, according to the USDA. And that’s been known to be the case for more than a decade.

There are many different types of nitrosamines and their formation depends on multiple variables, such as other ingredients, processing, storage, cooking, bacterial counts, and more. It was discovered in the 1970s, however, that simply adding ascorbates (vitamin C, ascorbic acid, sodium ascorbate, erythorbic acid or sodium erythorbate) to the salt cure inhibits nitrosation reactions which could lead to the formation of nitrosamines in processed meats. Since the 1970s, all commercially cured meats use sodium ascorbate, as well as monitor nitrosamine formation in fried bacon.

Gastroenterologists in the UK also discovered in 1989 that the healthy human stomach itself secretes appreciable amounts of ascorbic acid in gastric juice which prevents endogenous (in our bodies) nitrosamine formation when we ingest nitrates and nitrites. Our bodies appear designed to safely eat levels of nitrates and nitrites typically in foods and water.

So, just as there is no credible evidence for higher rates of gastrointestinal cancers among vegetarians who eat lots of vegetables and high-nitrate diets, there has been no evidence of higher rates of cancers because people eat larger amounts of meats or processed meats.

“The public perception is that nitrite/nitrate are carcinogens but they are not,” said Dr. Nathan Bryanm Ph.D., with the Institute of Molecular Medicine at the University of Texas in Houston. “Many studies implicating nitrite and nitrate in cancer are based on very weak epidemiological data. If nitrite and nitrate were harmful to us, then we would not be advised to eat green leafy vegetables or swallow our own saliva, which is enriched in nitrate.”


Nitrites good for you?

As the EFSA report explained, nitrogen is the most abundant chemical element in the earth’s atmosphere. It’s a key component of essential biomolecules such as amino acids, vitamins, hormones, enzymes and nucleotides. Found in all living tissues, nitrogen is an fundamental part of the nitrogen cycle, which continuously interchanges nitrogen between organisms and the environment. Since nitrite is produced naturally in our bodies and also naturally comes from our foods, it shouldn’t be surprising that it is not only safe, but a necessary and normal part of human physiology.

As studies failed to support the premise that dietary nitrate is detrimental to human health, the benefits and function of nitrites began being recognized. In 1994, Dr. Jon Lundberg, M.D., Ph.D., of the Karolinska Institutet in Stockholm, and Dr. Nigel Benjamin of Peninsula Medical School in Exeter, England, independently noted that the human stomach holds large amounts of nitric oxide. Knowing that it weakens microbes, they suspected it might be killing germs in the stomach, too.

As researchers at the University of Aberdeen described nearly ten years ago in the British Journal of Nutrition, the oxides of nitrogen, that are formed in the acidic stomach after swallowing salivary nitrites, have antimicrobial action against a wide range of gastrointestinal pathogens, such as —

• Yersinia enterocolitica

• Salmonella enteritidis

• S. typhimurium

• Shigella sonnei

• E. coli O157:H7

• Helicobacter pylori

• Candida albicans

The antibacterial action increases with nitrate concentrations, they found. Gastric pH rises after food is eaten to levels that are not bactericidal against foodborne pathogens unless nitrite is present. So, nitrites appear to have a biological function to help protect us against stomach infections and foodborne illnesses. Dr. Benjamin also noted that cavity-causing bacteria die in high-nitrite environments and suggested that nitrite may play a role in preventing cavities.

The role of nitrites, saliva and nitric oxide in our body continues to be researched, most notably by fascinating experimental studies being conducted at the Karolinska Institutet and the National Institutes of Health in Bethesda, MD.

Nitrites are being studied for possible pharmacological roles in various medical treatments, including in hypertension, heart attacks and sickle cell. Doctors at Karolinska Institutet, for example, are looking at the role of nitrites for intubated intensive care patients (who don't swallow their saliva) in preventing ischemia-reperfusion injury, gastric ulcers, and cerebral vasospasms after subarachnoidal hemorrhage, and in neonatal pulmonary hypertension. A 2005 thesis by Dr. Håkan Björne, M.D. described this in detail.

Nitric oxide and S-nitrosothiols have been shown to have vasodilator properties (playing a role in regulating blood pressure) and modulate platelet function in the human body. Nitrite has been studied as a vasodilator in mammals for over 125 years, said professor Bryan. In 2003, scientists at the NIH conducted a physiological study to explore the circulatory role of nitric oxide, made in the body naturally from nitrite. Their small study of 18 healthy volunteers showed that intravenous nitrite could improve blood flow 175%, by opening blood vessels and increase oxygenation to tissues, making it “a potential new treatment for diseases like high blood pressure, heart attacks, sickle cell disease and leg vascular problems.” According to lead author, Dr. Mark Gladwin, M.D., senior investigator in Critical Care Medicine at the Department of the NIH Clinical Center:

Nitrite levels have been shown to be low in patients with high blood pressure... Nitrite helps get more blood to regions of the body with low oxygen, such as kidneys, the heart, the brain and muscles. This has potential as a new therapy that was previously overlooked. It's a powder sitting on the shelf and everyone has it.

Along these same lines, a 2005 study by scientists with the National Heart, Lung, and Blood Institute with investigators supported by the National Institute of Diabetes and Digestive and Kidney Diseases at Louisiana State University Health Sciences Center, found that sodium nitrite infusions led to the production of nitric oxide which increased blood flow and protected the hearts and livers in mice undergoing experimental heart attacks and liver injuries, reducing heart muscle and liver tissue damage.

All of this experimental research is preliminary but does illustrate that in the past 15 years, “we’ve gone from considering all of these things to be toxic and carcinogenic to realizing that [nitrites are] playing a fundamental homeostatic role,” said Dr. Ferric Fang, M.D., professor of laboratory medicine and microbiology at the University of Washington in Seattle. They’re a normal, natural part of a healthy body and not chemicals to fear.

So, hotdogs and processed meats are condemned as junk food because they contain nitrates, which they don’t, while vegetables are declared health food because they’re free from the same chemicals, which they’re not. It may be awhile before people will get to the point of calling bacon and hotdogs health food.

But, at the very least, said Dr. Gladwin, perhaps we should feel less guilty about eating hotdogs at the ball park.

There’s still plenty of summertime left and lots of regional hotdog specialties and BLTs left to enjoy, along with those garden vegies. With a little more science under our belts, hopefully everyone can enjoy it all with a lot less worry.


© 2008 Sandy Szwarc. All rights reserved.


* Led by The Cancer Project, of the vegan organization, Physicians Committee for Responsible Medicine, directed by Dr. Neal Barnard, M.D.. This group has been censured by the American Medical Association, unfavorably reviewed by the National Council Against Health Fraud, and an investigative Newsweek article revealed it actually had fewer than 5% physician members, as well as ties to animal rights groups.

Addendum: A reader sent this example of The Cancer Project's hotdog scares targeting children here.


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July 28, 2008

Super juices

While the courts are not the venue to decide science, a case in the news can raise awareness of a widespread consumer fraud. One of the hottest functional food fads is super antioxidants juices. The more exotic and intensely colored the juices, and the higher their ORAC counts, the healthier they’re claimed to be. Pomegranate juice is currently the marketing heavyweight. There are some 950 products being sold in the United States, all claiming to contain pomegranates. The problem is, “there aren’t enough pomegranate groves on the planet to supply the products in the marketplace,” said Lynda Resnick, owner of POM Wonderful, LLC.

Consumers are being scammed and aren’t always getting what they think they’re buying.

To say that the super juice marketplace is competitive is an understatement. One of the largest pomegranate companies is POM Wonderful, which reported sales of $165 million last year of its California pomegranate products. According to U.S. Federal Court documents, the company says it was the first to market pomegranate products in the U.S. and has invested millions of dollars to fund research on pomegranate polyphenols as antioxidants that neutralize free radicals, to promote their promise for cardiovascular health and to inhibit more than a 100 different cancers and chronic diseases of aging, including Alzheimers, dementia and diabetes.

It filed a lawsuit against one of its competitors, Purely Juice, Inc., for selling a product labeled as 100% pomegranate juice that it says wasn’t pure juice. According to Ad Week, POM Wonderful wasn’t pleased with the fact this competitor was undercutting them in price while also using their own research on pomegranates in their marketing.

The court documents describe how POM Wonderful had Krueger Food Laboratories test a Purely Juice sample, which reported on February 21, 2007, that the sample “contains little or no pomegranate juice. The solids consist primarily of corn syrup and nonpomegranate fruit juice.” Food Research then tested samples being sold at three different locations in California and Virginia and sent them to seven independent laboratories. The consensus of the labs was that the juice wasn’t 100% pomegranate juice, but contained added sugars and other juices. The court ruled in favor of POM Wonderful and has ordered Purely Juice to pay $1.5 million in damages.

But the real story for consumers isn’t in this court battle. The helpful information for the public comes first in an important fact pointed out in the 27 pages of court documents — one widely known in the food industry, but few consumers have ever heard. The second and most important information wasn’t found in the court documents at all.


Buyer beware

As the court documents noted, companies buy juice concentrates and extracts from around the world which they reconstitute, but:

It is widely known that the market for foreign pomegranate juice concentrate was experiencing a problem with adulteration. In 2006, it was widely known in the super premium juice industry that there were serious issues of adulteration with pomegranate juice concentrate originating from outside of the United States.

So, even when you think those exotic juices you’re buying are 100% juice as the label says, what you’re actually getting may not be what you think. And these juices aren’t cheap, either, typically around $4 for a small bottle.

More importantly, you’re most likely to not be getting those wondrous health benefits being claimed. Everywhere we turn, another news story is touting near magical abilities of exotic berry and fruit juices — their antioxidants are purported to guard against free radicals and protect against age-related diseases, cancers, heart disease, and dementia; reduce blood pressure, reduce inflammation, help erectile dysfunction, and prevent muscle injuries.

Like that widely circulated story picked up by CBS News, many recent stories have originated from Health Magazine, owned by Time Inc., which supplies content to its partners who include the online health encyclopedia, Healthwise, the daily health news source for editors and writers, HealthDay, and online health and wellness symptom checker, Healthline. This story reported of a new University of California study ranking pomegranate juice as the best anti-oxidant juice. What readers weren’t told is that this story came from a press release from POM Wonderful, which funded the study, and was only measuring the polyphenol content and free radical capacity of various juices in the laboratory. It was not a randomized clinical trial evaluating any actual health benefits in people. As the POM Pomegranate press release notes, it has spent $23 million over the past decade to publish ten studies on the benefits of its pomegranate juice.

What the media isn’t reporting is the science behind these super foods and juices, including what every sound randomized controlled clinical trial of antioxidant vitamins conducted since 1945 has shown. We all want to believe there are special foods and supplements that can protect against aging and chronic diseases, and there are plenty eager to sell us on that belief. But that won’t make the promises credible.

The FDA cannot go after each and every company marketing pomegranates and super juices and superfoods, and making fraudulent health claims that have no clinical trial substantiation. But for years, it has been issuing warning letters to companies selling these products and consumers need only to “step and repeat” these warnings when the next commercial and health story comes along.


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July 26, 2008

Turning down the child care alarm

At every turn, new parents are being given another worry. This month, news has been reporting that babies cared for by people other than their parents gain more weight. A new study was reported as finding babies placed in day care, even in the care of a relative, were more likely to be fed improperly.

Almost instantly, mothers who had to go back to work or school after their maternity leaves, and unable to stay home with their babies, were being guilted out. Speculations as to why babies in child care might gain more weight ran from mothers not breastfeeding to caregivers more likely to pacify an irritable baby with milk or to give solid foods too early. The study, however, provided no evidence to support such assumptions, so before any more blame is directed at parents for having fat babies, let’s look at the study and the information media didn’t report.


Overview

Published in Archives of Pediatrics and Adolescent Medicine, this paper was not reporting the results of a randomized intervention trial, but an epidemiological study that had looked for correlations among part of a database of babies who had been enrolled in the Early Childhood Longitudinal Study, Birth Cohort study. The 14,000 children participating in the ECLS study were a representative sample of babies born in 2001 in the United States, with an oversampling of Asian and Pacific Islanders, American Indians, twins, and infants with moderately low and very low birth weight.

During October 2001 and December 2002, the ECLS team had done home visits of 9 month-old babies and gathered information, which included the following things used in this analysis:

· Parents had been asked about child care, including the type, hours in care, and the age when the baby first entered care. No child care providers or facilities were actually evaluated.

· Parents had also been asked when solid foods (referring to cereal and baby food in jars) were introduced, but there were no records on how often, the amount, or type of solid foods any of the babies had consumed.

· Babies’ lengths were measured and, using a bathroom scale, the mothers were weighed holding their baby and then the mothers’ weights were subtracted. The imprecision of bathroom scales, of course, lends caution to interpreting small variations.

For this analysis, Dr. Juhee Kim of the University of Illinois at Urbana-Champaign and co-investigator Dr. Karen E. Peterson of Harvard School of Public Health, Boston, selected 9,650 babies, 8 to 14 months of age, from the ECLS database. No explanation was given for why 4,350 babies were eliminated from the original study population. They further eliminated babies born to mothers younger than 15 years old and those under 32 weeks gestation; and another 6% for inadequate data. They conducted their analysis on 8,150 babies — 58% of the original ECLS participating children.

Using statistical modeling, the authors looked for correlations between weight gain, child care and introduction of solid foods among this data.

The babies in full-time day care differed from the other babies in several notable ways. A higher percentages of babies in full-time day care had been preemies or low birthweight babies. The babies who had been placed in child care earliest and more likely to be in full-time day care were also more likely to be black, with full-time working mothers, or unmarried mothers.


Findings

By 9 months of age, more than half of the babies in this cohort were in child care, most with relatives. Of those, about half were in child care full-time.

Months in child care. About 22% of the babies had been placed in child care before 3 months of age and these were the babies who gained the most weight during their first year of life. And the babies who had been in child care the fewest number of months (who didn’t begin child care until they were 6-11.9 months of age) or those who were cared for by their parents, gained the least.

But stop the presses: it was a difference of 8 grams — 0.2 ounces. Less than the weight of a baby poop.

Full-time versus part-time in child care. Weight gains associated with babies cared for by their parents were lowest (6001 grams), followed by those in day care part-time (6159 grams) and full-time (6190 grams). This was a difference in the raw (unadjusted) data of 6.6 ounces over the first year. But wait: before you jump to conclude it was the child care, remember those other correlations.

More of the babies in full-time child care were preemies or low birthweight babies. In other words, these were the babies with different growth patterns and more likely to gain more weight and to exhibit catch-up weight gains during the first few years of life. Higher weight gains among these babies could be a healthful sign and reduce their morbidity and mortality, not a negative. “Premature infants with intrauterine growth retardation and no catch-up growth have a higher risk of developmental delay and other medical problems than premature infants with a normal growth rate,” explained doctors David Trachtenbarg, M.D., and Thomas Goleman, M.D., in a recent issue of American Family Physician.

Regrettably, we have no information on the health or specific birthweights of the babies used in this analysis. The babies in full-time day care were, however, more likely to be born to black mothers with higher maternal weights. Pediatricians, knowing weights and heights are largely genetic, anticipate babies to take after their parents and grow larger. These authors recognized this genetic fact and factored for it in their analysis of odds ratios coming up...

Growth and development. Reports have been quick to assume that the greater weight gain among the day care babies, even as nominal as it was, was a bad thing. Not a single reporter stopped to consider the possibility that it was healthful, normal for those particular babies and a good sign. The quick assumption has also been made that this weight gain meant “overweight” or babies that were too fat. But we have no information on where any of the babies fell on their individual growth curves or if they were gaining more than would be anticipated given their birthweight, health and family genetics. Medical professionals compare each baby’s growth to how they follow their individual growth curve, not compared to other babies by pounds and ounces.

Variations among lengths and weights of babies naturally fall into a range, similar to the bell curve. But about a third of a pound difference in weight gain over a year among all of the babies in this cohort, however, does not an “overweight” baby make. Nor do variations in childhood growth patterns predict adult obesity, as has been covered extensively.

The authors reported that only birthweight was a significant factor in weight gain among the other correlations. No breakdowns were provided. But here they are also describing that large term babies, for example, even while gaining the same percentage of body weight as smaller babies, would naturally gain more weight when measured in pounds and ounces. Once again, each baby’s growth and development can only be evaluated using his/her individual growth curve.

Solid foods. The feeding data used in this data dredge were pretty crude measures — parental reports only of the age solid foods were begun and if breast feeding had been initiated. As this study shows, it’s easy to make assumptions about causations from correlations... assumptions that aren’t supportable.

There was only one tenable odds ratio reported in the entire study. Among the correlations between feeding practices and types of childcare, the preterm or low birthweight babies were three times more likely to have been introduced to early solid foods in daycare settings (RR=3.18, CL 1.27 to 5.08).

But there was no consistent relationship between early solid foods and when babies were placed in childcare (at birth, 3 months or 6 months of age). Underweight babies starting daycare at 3-6 months of age were no more likely to have begun solid foods early than those cared for by their parents. Once again, we can’t jump to conclude that child care was at fault.

Reflux, for example, is not uncommon in premature or small babies and some pediatricians recommend cereal to help reduce their symptoms. There were no other details provided about the small babies placed in childcare, their health conditions, or what the care providers may have been asked to feed these babies when placed in their care.

And remember, none of the babies’ actual dietary intakes were measured or followed, so we have no idea what or how much any of them really ate. Instead, a lot of groundless assumptions have been flying around, insinuating that child care workers were force feeding babies to pacify them.

So, while an association was reported between the age when solid foods were introduced and weight gain, and babies in child care (in a cohort of higher percentages of preemies and low birthweight babies) had higher odds for early introduction of solid foods, the authors were quick to add: “However, we found no mediating role for early introduction of solid foods in the hierarchical regression models of weight gain.”

They also reported “no effect of introduction of solid foods on weight gain among preterm and LBW infants. We were not able to show the potential mediating role of infant feeding practices between the observed risk of child care and weight gain.”

Breast feeding. The initiation of breastfeeding and child care naturally correlated, as mothers having to go back to work or school and needing to place their babies in the care of others during the day are less likely to breast feed. But, that doesn’t necessarily mean that it was the breastfeeding that explained the slightly lower weight gains among the stay-at-home babies. As the authors wrote: “We found no protective effect of breastfeeding on weight gain.” Nor was breast feeding and solid foods predictive of weight gain.

As they wrote:

We found no interaction between breastfeeding initiation and early introduction of solid foods in predicting weight gain. Findings were consistent with lack of association of breastfeeding initiation to weight gain among all infants and term and NBW infants, whereas breastfeeding initiation was associated with less weight gain among preterm and LBW infants.

Media has been quick to suggest that the association between child care and infant weight gain is evidence mothers should breastfeed to prevent obesity in their children. Not only did they not read the study, but the body of evidence has never supported this widespread belief. As with all transient changes in health indices, they are not predictive of actual or long-term clinical outcomes. Breastfed babies have different growth curves in infancy, with no effect on later body weights. Weight or diet in infancy or childhood is not predictive of adult body weight.

· The World Health Organization-Food and Agriculture Organization of the United Nations (FAO) 2003 report, Diet, Nutrition and The Prevention of Chronic Disease, noted that most of the 20 studies, involving 40,000 babies, that have examined the role of breastfeeding in overweight have found no relationship. It’s easy to be led astray by failing to consider confounding factors, such as genetics and socioeconomics, among studies in developed and underdeveloped countries.

· Two studies published in the October 2003 issue of the British Medical Journal concurred. One, funded by WHO and Canada’s International Development Research Centre, was released as “the largest such study done in the developing world.” It followed 2,584 babies born in 1958 for 33 years and found no association between breastfeeding and adult weights. Breastfeeding did not protect against obesity later in life. The researchers added: “Secular trends do not suggest a protective effect: in both Britain and the United States the incidence of breast feeding has increased since 1990, but so has obesity.

· The recent study of 240 fat Latino young people led by Dr. Jaimie N. Davis, Ph.D., at the University of Southern California, Los Angeles, found no protective effects of breastfeeding on adiposity or risk for type 2 diabetes.

· And an investigative study of the government’s promotion of breast feeding as a strategy for reducing childhood obesity, led by researchers at Harvard Medical School in Boston, followed 35,526 mothers and babies from 1989-2001. They also found no association between breastfeeding and risk for overweight or obesity in adolescence or adulthood, even among kids who were leaner at age 5. They concluded that breastfeeding “is unlikely to play an important role in controlling the obesity epidemic.”

New parents are surrounded by people eager to tell them how best to care for their babies or quick to criticize them for not doing something right. The trouble is, few pop beliefs or media stories are true or give the full story. Loving parents deserve to trust that when they make decisions they feel are best for their babies and families, they most likely are.


© 2008 Sandy Szwarc


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Little kids are not grenades

Making claims that scream more hysterically of an impending cataclysm of dead bodies still won’t change the evidence. Nor will aiming another scare strike at children. Now, we’re all supposedly under threat of a ticking cancer time bomb.

While its Second Expert Report had been unable to find any tenable associations between body fatness or diets and cancers after reviewing 2,471 studies on 17 cancers, a World Cancer Research Fund spokesperson was quoted in the Telegraph today, warning that because of growing numbers of fat children, they’re storing up future cancer cases and creating a ticking cancer time bomb. Actually, the WCRF website shows that no new press releases or research has been released, so this story would appear little more than creating news on a slow news day, using fat kids.

Raising the panic bar won’t change reality. The Health Survey for England data shows there’s been very little change in child obesity rates over the past decade. As Dr. Peter March, co-director for the Social Issues Research Centre in Oxford, UK, had concluded: “There have been no significant changes in the average weights of children over nearly a decade. This can be taken as evidence that there has been no ‘epidemic’ of weight gain.”

And while the Telegraph also claims that soaring childhood obesity rates are predictive of a doubling of cancer rates in America by 2050, this doomsday forecast isn’t supported by any evidence here, either. And, as scientists at the National Center for Health Statistics at the U.S. Center of Disease Control and Prevention concluded after reviewing 40 years of actual NHANES and vital statistics data on 2.3 million Americans: there are no viable associations between overall cancer mortality and any BMI category. They found no credible evidence to support beliefs that anyone dies of fat: “Our results showed little or no association of excess all-cancer mortality with any of the BMI categories. None of the estimates of excess deaths was statistically significantly different [from null].”

News isn’t always news. And kids are not little hand grenades waiting to grow up into cancer bombs.


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