Archive for December, 2007

The Perils of Crossing the Establishment Boundaries on Dietary Advice

Two opinion pieces in USA Today bring forth the very problematic issue of dietary advice when dispensed by a practicing physician and that advice happens to be contrary to the conventional wisdom.

In the first, Doctor’s dietary advice for diabetics not enough, Connie B. Diekman, president of the American Dietetic Association – Chicago, goes to great lengths to reinforce the notion that doctor’s are the wrong source of dietary advice and that Registered Dietians are “are more educated about the science of food and nutrition than any other health care professional, but they also know how to translate that science into useful, practical advice that anyone can understand and follow.”

She also says that “Dietitians do not simply hand a person a menu. A registered dietitian takes into account a person’s age, weight, blood cholesterol levels and other medical needs to develop a plan that is right for that person.

There is no “one-size-fits-all” eating plan for managing diabetes. Patients need to pay attention to portion sizes, timing of meals and specific food choices. They need to eat smart, avoid weight gain and balance the day’s food choices with regular physical activity.

A registered dietitian is the best source of advice in all these areas.”

In the second, Eat in moderation, the CEO for the American Association of Diabetes Educators – Chicago, Lana Vukovljak, weighs in with – “By touting his “five-fingered diabetic diet” as the key to weight loss and controlled blood glucose, he is perpetuating misinformation and doing his patients a disservice. Eichenbaum advises patients to avoid “bread and baked goods, potatoes and root vegetables, rice, pasta and fruit except for berries.” But that diet severely restricts meal plan options, ignores cultural preferences and lifestyle needs, and often results in increased non-compliance. Dietitians and diabetes educators stress the necessity of dietary changes and physical activity. Instead of making broad dietary directives that eliminate entire food groups, however, they encourage moderation and reduced portion sizes. They also make dietary recommendations that factor in an individual’s cultural tastes and lifestyle requirements.

Diabetes education helps people incorporate behavior change into their lives by personalizing recommendations and simplifying nutritional messages.”

It appears whatever was written by Eichenbaum caused a big stir – two major organizations responded with very clear implications that the author was unqualified and potentially dangerous to patients well-being, thus readers need to ignore whatever it was that appeared in the paper.

What exactly caused the hub-ub?

Well, it was another opinion piece in USA Today, Simple diets work best with diabetes, written by a Dr. Dan Eichenbaum, MD who is an opthamologist in North Carolina.

In that he had the audacity to write, “In numerous studies, elevated blood sugars have been linked to diabetic vision loss despite potentially successful medical and surgical treatments. Medication should be used to control blood sugar only after an optimum diet and exercise regimen has been established.

Most patients, however, expect medication to control blood sugars no matter what they eat. They adjust insulin or pill dosages to cover their dietary indiscretions. Unfortunately, dieticians routinely give patients complex diets that require a ruler, a scale and a calculator. It is no wonder that few diabetics can adhere to these elaborate eating regimens.

I explain to my patients that eating carbohydrates is like putting diesel fuel in a vehicle that can only run on gasoline.

Just as a gas engine won’t burn diesel, a diabetic’s “engine” cannot burn carbohydrates.”

But, he didn’t stop there, he also included foods he specifically tells his patients to avoid – bread, pasta, potatoes, baked goods, root vegetables, rice and even fruits except berries. He keeps it simple and says “Patients who eliminate these items lose weight and can easily control their sugar levels. Expecting patients to abide by a diet that is difficult to follow causes non-compliance and increases their risk of blindness.”

I point to these today because they highlight the position many clinicians are in when it comes to offering patients dietary advice – they’re squarely between a rock and a hard place.

If Dr. Eichenbaum had instead penned something that simply regurgitated the current party-line dietary guidelines, do you think there would have been a similar response questioning his qualifications or patient care?

Hey, have you ever seen Dr. Mehmet Oz slammed in the mainstream media or have his qualifications questioned when he appears on Oprah or Larry King Live espousing the consensus opinion for dietary recommendations?

Of course not – he’s preaching the consensus opinion and therefore what he says is okay, his apperances are even highly promoted with viewers encouraged to watch and listen to him. This despite the fact he is not a registered dietitian!

See, as long as your advice is aligned with the consensus, you’ll be fine; step outside the boundaries publicly and you’ll quickly find your advice ridiculed by the establishment, along with having your qualifications challenged and the clear implication that your patients should wonder if you’re harming them!

It does not matter if you’ve based your advice on hard data from peer-reviewed studies; it certainly doesn’t matter that your training as a physician included statistics, biochemistry, biology and other pertinent subjects; and it doesn’t matter diddly that your patients see improvements when they follow your advice – what matters is you’ve crossed the line and made it public that you’re dispensing nutrition advice contrary to the current dietary recommendations published by the leading health organizations and you’re not a “registered dietitian” to boot.

The above responses to this doctor’s words drive home one of our biggest challenges in public healthcare today – the consensus-driven-model that explictly endorses dogma trumping the evidence-based model.

All one needs to do to begin to truly understand how deep this consensus-based-model runs, is to take some time to read through various position statements published by the leading health and medical organizations about what they recommend for diet to clinicians in practice and the public.

Take the American Heart Association position paper on diet, you’ll find it’s almost identical to that issued by the American Diabetes Association, which is itslef almost identical to that issued by the American Dietetics Association, which is basically the same as the American Cancer Society – the list goes on and on as to this universal message contained within each position statement published by these organizations.

These documents are often held up as the “standards of care” for use in medical practice, informing the clinican that they’re written from and based upon the best available evidence, brought together by committee and agreed upon through consensus of those bringing the document together for publication.

These position papers also routinely include references to the alternative approaches that have support in the data, but these are routinely dismissed as inconclusive, deemed controversial, inappropriate or potentially harmful, with the explicit message that no one should advise such an approach to any patient because the evidence is not strong enough. Noticably absent are those studies with the strongest data, while those studies with findings considered minor enough to dismiss are included and highlighted to make the position against their efficacy appear strong.

The interesting thing is, in various position statements, there is a very clear consensus between the organizations when it comes to dietary recommendations – they’re all making the same basic recommendations, they all claim to be based on the best available evidence, and they all affirm similar beliefs about macronutrient ratios in a “healthful diet,” which leads anyone reading them to believe they’re supported by research and evidence from high-quality data. Surely they must be right if all agree on the simple basics!

Wait…wait…wait…..no one seems to ask – are they all so similar because the evidence is so strong and supportive of the dietary recommendations contained within, or are they simply the result of long-held beliefs and dogma driving consensus across organizations?

You can actually begin answer that question yourself.

Simply get your hands on at least three to five position statements from different medical organizations about their dietary recommendations. Then, if you want, you can read them all, but you don’t really have to since they’re all likely the same bottomline message anyway.

No matter what, your real investigation about the underlying forces driving how the statements are prepared starts in the references.

Look at and compare them in each and between each paper and you’ll start to see how they point to each other as basis for supporting evidence and consensus.

It really doesn’t matter what organizations you choose – you’ll find this “circular reference tactic” within them all, with NONE actually providing conclusive hard data to support their position. They don’t need to actually provide mountains of supporting data because with the circular reference tactic, they have each other, and by pointing to the other as supportive and evidence-based they imply the data is “over there” without really doing anything more than taking anyone following the references on a wild goose chase while maintaining the status quo for the the party-line dogma about diet and health.

Then foot soldiers within these organizations will criticize and challenge anyone who dares to not only look beyond these circular reference tactics to find solid evidence that points to an alternative approach, but then actually recommends the alternative to patients and says they do in a public forum, like the media. Such challenges to the status quo simply cannot and will not be tolerated as we can see from the responses above to one doctor who did just that.

Given the strong and dire warnings about the “obesity epidemic” in our country, isn’t it time we actually look at the literature and see what the data contains and really hammer out a true evidence-based model of dietary recommendations for the public?

Isn’t it time for us to move past this idea “we know” what works, to actually go find out what works based on data and hard evidence?

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December 18, 2007 at 7:48 pm 14 comments

Glycemic Index Doesn’t Matter Much in Overall High-Carb Diet

Ever wonder what would happen if you place 19 obese, hyperinsulinemic women on a diet where calories aren’t restricted, but glycemic index is tweaked a bit?

The short answer – not much when you look for differences between diets that are high or low glycemic index.

But y’all know I’m not about the short answer already, so how about we take a look at a newly published study, No effect of a diet with a reduced glycaemic index on satiety, energy intake and body weight in overweight and obese women, that has some very interesting findings that were notable but ignored in the paper.

Make a note of the paper title, it’s important later!

Let’s start with some background. For this study, researchers recruited otherwise healthy, obese women who had hyperinsulinemia. They were free of underlying conditions like diabetes, were not taking medications for cholesterol, hypertension or other medical conditions, were not pregnant or breastfeeding, and had not recently dieted to lose weight, nor recently lost or gained weight, thus deemed “weight stable” to participate.

The researchers then determined their habitual food intake and calories consumed each day, noting the subjects consumed an average of 1859-calories/day – 48.8% carbohydrate, 16.7% protein and 34.4% fat [227g carb, 77.6g protein, 71g fat].

The study was then underway, with the women consuming one of two diets for 12-weeks in a cross-over design, so the study lasted a total of 24-weeks. The objective of the study was to “investigate whether a diet with a reduced glycaemic index (GI) has effects on appetite, energy intake, body weight and composition in overweight and obese female subjects,” so the researchers provided cereals, breads, rice, pasta and potatoes with different glycemic index for the women to consume while following either the low or the high glycemic diet.

The women were told to consume their foods as they did in their habitual diet and continue eating how they usually ate before starting the study.

In the paper, the researchers noted that “[t]here were no differences in energy intake, body weight or body composition between treatments. On laboratory investigation days, there were no differences in subjective ratings of hunger or fullness, or in energy intake at the snack or lunch meal.”

They concluded, “This study provides no evidence to support an effect of a reduced GI diet on satiety, energy intake or body weight in overweight/obese women. Claims that the GI of the diet per se may have specific effects on body weight may therefore be misleading.”

Yesterday, Sandy Szwarc at Junkfood Science blog penned her article Carbs humbug? — Are carbs really fattening? about the study, with her perspective being that this is one more piece of evidence that carbohydrates are not fattening.

She wrote, “Despite oft-repeated fears that refined “bad” carbs send our glucose and insulin levels soaring, these researchers found “no differences in glucose, insulin and non-esterfied fatty acid responses to the lower versus higher GI breakfasts, with no differences in either total area under the curve or single measurements at any time point.” Concerns that carbohydrates in the diet stimulate insulin production and are responsible for obesity and illness were recently examined here.”

I point to the article at the Junkfood Science blog because it’s a good example of seeing the forest while missing the trees.

Let’s look at the data in the study now, comparing the dietary changes with their baseline starting values…with the baseline number first, followed by the measured effect of each diet (values are rounded up or down where appropriate).

Low-Glycemic Index Diet, 12-weeks
Baseline – Low-GI Diet
Weight: 87.5kg – 89.1kg
Waist: 103cm – 105cm
Fat Mass: 42.3kg – 44.54kg

Calories: 1859/day – 1928/day
Carbohydrate: 227g/day – 248g/day
Protein: 78g/day – 82g/day
Fat: 71g/day – 69g/day

High-Glycemic Index Diet, 12-weeks
Baseline – High-GI Diet
Weight: 87.5kg – 89.2kg
Waist: 103cm – 106cm
Fat Mass: 42.3kg – 42.9kg

Calories: 1859/day – 1874/day
Carbohydrate: 227g/day – 223g/day
Protein: 78g/day – 83g/day
Fat: 71g/day – 71g/day

The researchers didn’t spend much time in the paper discussing the weight gain, fat mass increase, or change in waist circumference. In fact, they noted “[t]here were no differences in body weight, waist circumference or fatness between intervention periods. Weight increased during both intervention periods, although weight gain did not differ between treatments.”

They didn’t discuss the differences from baseline, nor seek to understand how it is that hyperinsulinemic women, who are obese, gained both weight and body fat while consuming diets that were not that much higher in calories than baseline – certainly not high enough to theoretically gain as much as they did!

But more importantly – look at the increase in waist circumference – more than one inch (3cm) is not something to sneeze at in just 3-months, nor is the scary gain of 4.9-pounds of body fat while consuming the low-GI diet for 12-weeks!

Why did that happen?

The researchers didn’t discuss the possibility that high insulin played a role or that blood glucose from carbohydrates consumed had anything to do with it.

Perhaps it happened because insulin and blood glucose didn’t budge?

The paper does not include baseline values of insulin and glucose in the table to compare it to each diet, but does provide a telling look at how dietary glycemic index, in the context of a high carbohydrate diet, when compared with each other had no effect on either:

And in case you missed it, what this showed, quite nicely I’ll add is that 12-weeks of a high carb diet – whether the perceived junky high-GI or “healthy” low-GI carbs – can make you gain weight, body fat and see your waist grow bigger too…while doing absolutely nothing to resolve a state of hyperinsulinemia!

But yeah, the brilliant conclusion was that there was no difference between low-GI and high-GI…let’s not confuse ourselves with the more important findings here!

December 14, 2007 at 9:26 pm 11 comments

Where Do We Go Now?

Not a day goes by without some mention in the media about the epidemic of childhood obesity. We’re reminded that there is a growing prevalence of overweight and obesity amongst our children and that we must do something to avert a health crisis in the future – overweight and obese children are at a higher risk for heart disease, type II diabetes and a host of other ailments. All of this is true.

We read and hear about all sorts of solutions – improve the diet of children, eliminate vending machines in schools and advertising to children on television, limit screen time for television, computers and video games, encourage more physicial activity, build more sidewalks so children can walk to school, increase physical education classes in schools, enroll children in programs that promote physicial activity, cook meals at home, eat with your children, eat fewer meals prepared outside the home, decrease juice consumption, eliminate sugary sodas, provide more fruits and vegetables each day, limit saturated fat and cholesterol, go for low-fat or skim milk and dairy, eat less fast food – the list goes on and on, boling down to the same tired advice for adults who are overweight or obese – eat less and move more.

Here’s a startling finding – data from various studies suggest that the cause of childhood obesity is not calories per se, nor is it inactivity.

In fact a large number of studies find that despite differences in weight, children of similar age consume similar calorie loads each day; and even that children engage is similar levels of activity. Simply put, the data suggests children who are overweight or obese do not overeat, nor are they sedentary when compared with their peers who are normal weight.

Other data finds that the numerous proposed interventions – actually tested in clincial trials to see what happens – do little over the long-term for children who are enrolled in various interventions. Yet we continue along the same path of hope, that modifying diet and increasing physical activity might work in the future.

What’s the problem?

The first problem is our focus.

In an ABC News article we find it articulated by Dr. Keith-Thomas Ayoob, associate professor of pediatrics at the Albert Einstein College of Medicine in New York, “Children who have been obese for much of their childhood will enter adulthood with chronic health problems that will only continue if their BMI remains high.”

So of course the solution is to reduce BMI and/or prevent it from ever reaching the threshold of being classified overweight or obese. No brainer, right?

Wee little problem – it’s a flawed solution that fails to address the underlying cause of the weight gain.

Which brings us to the second problem – seeing the weight as the problem, not the symptom it is.

We’ve reached the point where our list of potential solutions are all directly tied to the belief that obese children are fat, lazy and just eat too damn much, because that is the only place you can go when you believe that weight gain is simply a matter of calories in and calories out.

Taking that belief to the next step, you reach the idea that if you modify the calories in and increase the calories out, children will slim down and realize the health benefits long-term.

Yet there is no strong evidence that finds this works for the long-term – not in adults and not in children. But the lack of evidence has not caused us to pause in the past, so why should it in the present and future?

We absolutely need to step-back and take a critical look at what is really happening today. We’re telling our children that they’re too fat, lazy and going to die before their parents; we’re telling them that they’re going to have major health issues when they are adults; and we’re actively promoting the idea that their parents are failing them.

I cringe when I read most of the articles about childhood obesity today because what we’re setting up for the future of our children is pretty darn scary!

To me it’s not scary that the future is bleak for these children because they’re overweight or obese – no, it’s because we’re on the path to destruction because we’re focused on weight and BMI rather than the true underlying cause of weight gain in children, and even adults – insulin resistance, a nutritionally bankrupt diet and the cascade of metabolic derrangement from both.

Rather than address that, the powers that be focus on the overt symptom – weight gain – and design solutions based on assumptions that reducing calories and increasing activity will solve the problem.

But, we know from other studies, that body weight and BMI in children is a poor indicator of health and well-being.

A number of studies have found that even slim children can be insulin resistant and fat despite having a normal body weight and BMI.

In very young children, a study out of Sweden found that children with a higher BMI head a higher incidence of insulin resistance, yet consumed less fat but more sugar, despite consuming consuming similar calories each day as their healthier peers.

As I noted in my review of that study, “The summary says it all “A lower fat intake was associated with higher BMI and higher HOMA ß-cell function. fS-insulin and insulin resistance were associated to increased growth rate from birth to the age of 4 (upward centile crossing). Risk factors for the metabolic syndrome can be identified already in healthy 4-year olds, especially in girls.”

We ignore data, like that published in February 1998 – Diabetes Care; U-shaped and J-shaped relationships between serum insulin and coronary heart disease in the general population. The Bruneck Study, where researchers concluded, “Results of the present study suggest that both hyperinsulinemia and “hypoinsulinemia” are independent indicators of CHD. Furthermore, it is proposed that the relationship between CHD and fasting insulin is U-shaped, whereas that between CHD and postglucose insulin may be J-shaped.”

In June 2003 – Obesity Research; Fasting plasma insulin modulates lipid levels and particle sizes in 2- to 3-year-old children reported “Fasting insulin level was positively correlated with triglyceride levels and inversely correlated with HDL-cholesterol level in boys. Higher fasting insulin level was also correlated with smaller mean HDL particle size in both boys and girls and smaller mean LDL particle size in boys. The associations of fasting insulin level with triglyceride and HDL-cholesterol levels and HDL and LDL particle size remained significant after multivariate regression adjustment for age, sex, and BMI or ponderal index. Fasting insulin level is associated with relative dyslipidemia in healthy 2- and 3-year-old Hispanic children.”

Two and three year old children, already experiencing the health damaging effects of high insulin and high triglycerides!

But it’s the calories driving the overweight driving the long-term risk of heart disease.

Yeah, right.

I wrote, back in November 2005, about a study published that found the incidence of pre-diabetes in teens alarming. In that article I wrote, “What is fueling this disfunction is not a metabolism gone awry, but years of eating a poor diet and consuming what can only be described as excessive carbohydrate in a state of malnutrition. This excess of carbohydrate and a chronic failure to meet nutrient requirements is exhausting the metabolism – exhausting the body’s ability to produce and effectively use insulin.

It is time we change our perspective to one that addresses the underlying problem – poor diet – and stop pretending it isn’t the increase in carbohydrate, to excessive levels, in our diet that is causing the numbers of children, adolescents and adults that become obese to continue climb and the numbers being diagnoised with pre-diabetes and diabetes to skyrocket along with other symptoms like dyslipidemia and high blood pressure.

What was once a long-term “wear-and-tear” disease seen in older people is now, with increasing and alarming frequency, afflicting our children. When are we going to stand up and say “enough is enough” – how many millions of children must be diagnoised before we finally step up and truthfully state the problem and give parents the solution to try to prevent this in their children?

This isn’t rocket science.”

Two years later, we still aren’t addressing the real problem – we just continue to beat the drum that children are growing fatter because they’re eating too much and moving too little.

If we are going to have a real impact on the health of our children, we MUST step-back from the dogma based on failed ideas and interventions with adults, and begin to tackle the real issue here – our nutritionally bankrupt diet that contains exessive carbohydrate day-in and day-out.

Our children gaining weight is the symptom of this excess – an excess not of calories, but an excess of carbohydrate leading to an excess of insulin and blood glucose, leading to insulin resistance in younger and younger ages, and leading to existing health problems as they enter adulthood.

December 13, 2007 at 3:55 pm Leave a comment

Low-Carb, Too Much Stress on the Body? Say It Isn’t So!

After seeing the article Low carb diets may stress body too much, studies find, on Carol Bardelli’s blog, discussion about it on Active Low-Carber Forum, and receiving emails asking me about my thoughts on it, I decided perhaps it’s time to add a post here about it.

The article includes one important paragraph that I’ll focus on:

The ASU researchers Carol Johnston and Pamela Swan, along with collaborators Sherrie Tjonn and Andrea White, both registered dieticians, and Barry Sears, of the Inflammation Research Foundation and creator of the Zone diet, have published three papers during the last two years, appearing in Osteoporosis International, The American Journal of Clinical Nutrition and most recently in the Journal of the American Dietetic Association.

From the publications above, it’s claimed that researchers have found:

1. With these studies, their research uncovered that the ketogenic diet may increase bone loss because of an increase in acid in the body and not enough intake of alkalizing minerals like potassium to neutralize this effect. In addition, a higher percentage of calcium was found in the urine of those on the KLC diet, leading the researchers to believe that the bones are “leaching” calcium.

This would be the finding from the unpublished data included in a Letter to the Editor published in Osteoporosis. It was from a cohort following a low-carb diet or non-ketogenic low-carb diet for two weeks.

Two weeks?

Haven’t longer studies reached a different conclusion? The link I just provided is also in the journal Osteoporosis, but it’s from a three month study and in it, the researchers concluded, “Although the patients on the low-carbohydrate diet did lose significantly more weight than the controls did, the diet did not increase bone turnover markers compared with controls at any time point. Further, there was no significant change in the bone turnover ratio compared with controls.”

2. Another study by these researchers looked at the metabolic advantage of one diet over the other. They found that the reduction in fat loss and weight loss was about the same for both diets over a six-week trial. In addition, body mass index was significantly lower after six weeks in both diet groups. However, those following the KLC diet experienced a greater increase in LDL cholesterol than those following the NLC diet. HDL cholesterol did not seem to be impacted significantly.

This would be from a six week trial comparing the effect of a ketogenic low-carb diet and a non-ketogenic low-carb diet, where the researchers finding was as stated above.

Interesting little problem can be seen, however, when you go to the full-text of the paper – I’m very curious about what they fed (or recommended) those following the ketogenic diet – they managed to get 15g of fiber in them, yet failed to reach recommended intake for folate, vitamin E, iron, magnesium and potassium.

What were they feeding/recommending to these people?

Yes, this is a study I have serious questions about – because it is virtually impossible to miss folate if one is eating non-starchy vegetables as the majority source of carbohydrate, just as it is virtually impossible to miss vitamin E for the same reason. Add to this, failing to meet iron is next to impossible with the combination of meat and leafy greens when one is following a low-carb diet properly, and even magnesium and potassium should come in at levels at least above 80% of recommended intakes.

I even emailed Dr. Sears shortly after the paper was published, asking specifically, “I’m reading through your paper published in the AJCN this month and wondering what was on the menu for both groups? I see the macronutrient and micronutrient values, but am having some difficulty understanding what was provided for meals since some of the nutrient values are quite disparate (like the carbohydrate, cholesterol and polyunsaturated fats). Would it be possible to send me a day’s menu of each diet so I can better understand the types of foods the subjects ate during the study?”

Oddly, I received no reply – usually Dr. Sears replies when I email him a question, but with this request for information, he did not. Of course, my request remains open for him or any of his researchers to email me and until such questions are answered about actual food consumed on both diets, the data remains suspect in my opinion since we don’t know what was eaten to influence such a nutrient deficiency, which indeed may have influenced the outcomes seen!

3. They also noted that dieters on the NLC diet versus the KLC diet experienced more energy. Their most recent article published in October explains that the body needs carbohydrates for energy so if you are taking in an extremely low amount of carbohydrates and only receiving energy from protein, intense exercise is actually harming your body more than helping it. Without adequate amounts of carbohydrate stores, or glycogen, muscles rapidly fatigue during sustained exercise.

This is from a two-week trial. What’s with this two week data offered up as proof these days?

Folks, this one is just a no-brainer. Dr. Steve Phinney has found, and published that time to adapt to a ketogenic diet is required, and once adapted endurance returns to pre-diet levels. That the cohort reported being more fatigued in two weeks is not surprising – in fact, it’s expected. “Impaired physical performance is a common but not obligate result of a low carbohydrate diet. Lessons from traditional Inuit culture indicate that time for adaptation, optimized sodium and potassium nutriture, and constraint of protein to 15–25 % of daily energy expenditure allow unimpaired endurance performance despite nutritional ketosis.”

December 10, 2007 at 6:19 pm 14 comments

Vegetarian Diet in Pregnancy: Insulin Resistance in Children

For many years now there has been a push in the United States to convince the public they need to consume less animal foods and more plant-based foods. Earlier this year I reviewed our dietary habits based on consumption patterns in the US as documented by the Food and Agriculture Organization (FAO) and the Economic Research Service (ERS) of the USDA and was really shocked by the level of intake for added sugars, cereal grains and vegetable oils.

The most recent assault on common sense came this week when Newsweek featured The Fertility Diet on its cover, promoting it and the findings from epidemiological data that was the basis of the book as a proven way to eat to enhance fertility. As I noted in my review of the book and study earlier this week, the study findings and book “do not make a proven strategy or evidence-based approach to prevent or reverse ovulatory dysfunction.”

I didn’t write much about the potential effects on babies born to women consuming such a diet because the post was already very long. However, it needs to be discussed considering new data published this week. For all intents and purposes, The Fertility Diet is recommending a predominently vegetarian diet – limit red meat and animal foods, strictly limit saturated fat, favor protein from beans and include full-fat dairy. This is almost identical to how the population in India eats!

Blogging on Peer-Reviewed ResearchA study published in the January 2008 issue of Diabetologia, Vitamin B12 and folate concentrations during pregnancy and insulin resistance in the offspring: the Pune Maternal Nutrition Study, highlights the profound effect on the offspring of women consuming an habitual vegetarian diet. [link opens to full-text of paper]

In the abstract we learn the researchers set out to understand how elevated total plasma homocysteine concentrations predict birth weight and risk factors for type II diabetes – “We studied the association between maternal vitamin B12, folate and tHcy status during pregnancy, and offspring adiposity and insulin resistance at 6 years.”

To do this they followed 700 pregnant women in six villages (and their children) over six years; “We measured maternal nutritional intake and circulating concentrations of folate, vitamin B12, tHcy and methylmalonic acid (MMA) at 18 and 28 weeks of gestation. These were correlated with offspring anthropometry, body composition (dual-energy X-ray absorptiometry scan) and insulin resistance (homeostatic model assessment of insulin resistance [HOMA-R]) at 6 years.”

What the researchers found was not only disturbing, but may have long-term implications not considered critical to long-term health of children previously.

In the table presenting the maternal nutrition data during pregnancy, we learn the women consumed adequate calories – the majority did not consume meat, poultry or fish, but did consume dairy (milk, yougurt, cheese, etc.).

At week 18 of pregnancy, the majority of calories in the diet came from carbohydrate – 70%, fat contributed 17% of energy and protein 13%; at 28 weeks of pregnancy the dietary macronutrient ratios were similar – carbohydrate 72%, fat 16%, protein 12%. The women (without folic acid supplementation) consumed a diet righ with foods high in folate, as evidenced by the finding that only one woman in the whole group was deficient for folate – all others exceeded levels desired in pregnancy.

Alarming however was the finding that the majority were deficient for vitamin B-12 – 60% of the women had blood levels of B-12 less than 150pmol/l. While the finding was alarming, it was not unexpected since the women were not consuming meaningful intakes of animal foods from which we find vitamin B-12 in our diet – the majority of the women were vegetarian, consuming a high carbohydrate, low-fat diet – the type of diet, in fact, promoted in The Fertility Diet book.

The women in the study seem to have done well in their pregnancies and gave birth to healthy babies, some were low birth weight, but as I said, they were overall “healthy.”

So why then am I writing about this study?

Well, the effect on their children, over the next six years was telling and speaks volumes about how diet and micronutrient intakes during pregnancy may effect offspring.

When the researchers followed up on the children six years later, they found a seemingly healthy bunch of kids – “At 6 years, the children were light, short and had a low BMI compared with an international (UK) reference; none were overweight or obese as defined by International Obesity Task Force criteria.”

You would think that was good news, wouldn’t you?

Well, it wasn’t their outward appearance or their normal BMI that was problematic, it was their fatness and insulin resistance at age six that shocked the researchers!

“…skinfold thickness measurements showed that the children were relatively truncally adipose; the mean SD score for subscapular skinfold thickness was -0.42 compared with the UK growth standards, in contrast with -2.23 for weight and -1.86 for BMI. Higher fat mass and higher body fat per cent were associated with higher fasting insulin concentrations, higher HOMA-R and higher 120 min plasma glucose concentrations (p = less than 0.05 for all).”

A few paragraphs later we learn, “The highest HOMA-R was in children whose mothers had the lowest vitamin B12 and highest folate concentrations.”

What this means is that the children born to women consuming the highest levels of folate rich foods – green leafy vegetables and beans – and the least (or none) animal foods, had children with the highest risk of insulin resistance!

The researchers opened their discussion section bluntly, “We have demonstrated for the first time in a purposeful, community-based prospective study an association between maternal nutritional measurements in pregnancy and two major risk factors for type 2 diabetes in the offspring,” and didn’t stop there, “higher maternal folate concentrations predicted greater adiposity (fat mass and body fat per cent) and higher insulin resistance, and lower vitamin B12 concentrations predicted higher insulin resistance. Children born to mothers with low vitamin B12 concentrations but high folate concentrations were the most insulin resistant.”

They concluded with “…our data raise the important possibility that high folate intakes in vitamin B12-deficient mothers could increase the risk of type 2 diabetes in the offspring. This is the first report in humans to suggest that defects in one-carbon metabolism might be at the heart of intra-uterine programming of adult disease.”

If you are pregnant or planning to conceive, you may want to think twice before shunning foods that provide vitamin B-12 – meats, eggs, poultry, fish and dairy!

December 8, 2007 at 3:20 pm 7 comments

Free Copy of Protein Power

Drs. Mike and Mary Dan Eades have a special gift for you for the holidays – a first edition, hardbound copy of Protein Power Lifeplan – pay for shipping and the book is free!

Here is what Dr. Eades wrote on his blog today:

Through December 20 (after which it will be impossible to get the book by Christmas) we will give away a 1st edition hardcover (not a paperback) copy of the Protein Power LifePlan to anyone of our readers who wants it. That’s right, it’s absolutely free. The price is zero. (Click here to go to the product page on our website and order if you’re interested.)

And in the interest of disclosure, I’ve got no vested interest here – I saw Dr. Eades post and decided to share the love!

December 7, 2007 at 10:09 pm 2 comments

Jonny Bowden Responds to Beverage Association Spin

Earlier this year, in September, Jonny Bowden penned an article, Diet Soda No Bargain, on his blog.

He recently received an email from the Director of Communications, Tracey Halliday, for the American Beverage Association criticizing his article, saying it was “erroneous” and emphatically stated that “All of our industry’s beverages– including regular or diet soft drinks– can be part of a healthy way of life when consumed in moderation and as part of a healthy lifestyle.”

He responds on his blog.

Enjoy!

December 7, 2007 at 6:16 pm Leave a comment

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