Tuesday, June 22, 2010

Is your diet deficient in micronutrients?

That's what the findings of a recent paper that concluded 4 popular diets were deficient in micronutrients would state.

The paper in question took a look at micronutrient intakes if a person were to follow Atkins, South Beach, DASH or the Best Life diets, and from the very first sentence I knew it was going to be a tough read,

"Research has shown micronutrient deficiency to be scientifically linked to a higher risk of overweight/obesity and other dangerous and debilitating diseases"
Oh really? I guess it's a zinc deficiency that's leading people to consume more calories than ever before.

This read became doubly painful as I had to then read the reference that he was using to support his assertion that micronutrient deficiency and obesity are causally linked,
"Micronutrient deficiency has been shown to cause an 80.8% increase in the likelihood of becoming overweight or obese"
It was a study published in the journal Economics and Human Biology entitled, Micronutrient deficiency and the prevalence of mothers' overweight/obesity in Egypt and without spending too much time on that study which was also poorly designed, let me simply point out that data collected on a small sample of mothers in Egypt who were subdivided into the poor and the extremely poor, does not even if true, automatically extrapolate to the rest of the world except by authors stretching to find references to help make their papers seem more important.

Back to this paper, the author indeed demonstrates that following the aforementioned 4 diet plans people won't meet their micronutrient RDIs. What he didn't bother mentioning was that unless you're eating obesity inducing volumes of foods, regardless of what you're putting in your mouth, you're probably not going to meet your micronutrient RDIs and so really, if you're worried about micronutrients you should be on a basic multivitamin whether you're on a marquee diet or not. Instead the author makes this statement,
"The implications of this study are significant and far-reaching."

"Consequently, with global obesity being a very real and serious condition it should be of some concern to the millions of individuals worldwide, following one of this study’s four popular diet plans, or similar, using whole food alone, that based on the findings of this study, micronutrient deficiency is inevitable."
Scary sounding, but more nutritional fear mongering than truly concerning and an issue certainly not unique to dieters.

Ultimately this was a non-study. It was a completely expected result which the author spectacularized by inventing a causal link with obesity where there is none.

So imagine my non-surprise when I got to the end of the study and read this,
"JBC (the author) is the CEO of Calton Nutrition, a private corporation that researches the causation and prevalence of micronutrient deficiency worldwide. Due to the results of its research Calton Nutrition is in the process of developing a multivitamin"
Peer review, shmeer review.

(The most important (and not discussed) part of the study? If the author's calculations are correct the DASH diet, when followed, leads people to consume 2,200 calories - enough to cause weight gain for a woman with a healthy body weight.)

Calton, J. (2010). Prevalence of micronutrient deficiency in popular diet plans Journal of the International Society of Sports Nutrition, 7 (1) DOI: 10.1186/1550-2783-7-24