Weight Maven

Loren Cordain and colleagues have recently begun blogging over at the Paleo Diet, mostly Q&A posts from their readers. Well worth the subscribe.

This past Tuesday, they posted an interesting Q&A on insulin resistance and high glycemic diets (see second Q).

Cordain et al were asked to respond to McDougall’s claim that plenty of cultures do well on high GI diets.

Read the entire response, as it’s illuminating. But lest you think that it’s all about the amount of carbs or fat in the diet, I wanted to highlight the variables that Cordain et al suggest influence whether one culture or another can tolerate various diets (emphasis mine):

Exercise (it has a huge impact on insulin sensitivity and sarcopenia, a typical consequence of inactivity), leads to insulin resistance and an increased risk of the metabolic syndrome).

Vitamin D and/or ultraviolet exposure (for instance, in Kitava they don’t suffer from Vitamin D deficiency, whereas in the western world many of us do and there is evidence linking Vit D deficiency to an increased risk of Type 2 Diabetes and the Metabolic Syndrome, among various other diseases).

Magnesium deficiency is strongly associated to an increased risk of the Metabolic Syndrome and Cardiovascular diseases. Presumably this wasn’t a problem for our ancestrors and to many non-westernized populations, but it is a huge problem in the US.

Fructose intake – although our ancestors and many non-westernized populations around the world eat fruit, which is a source of fructose, fruit also has Vitamin C (which counteracts some of the adverse effects of fructose) and they don’t eat as much fructose as the Americans do, because HFCS has been added to many foods and because of the American eating habits …

[Note: Lustig also makes the point that Asian cultures may eat a lot of starch, but they are not getting anywhere near the amount of fructose we are.]

Bioactive peptides and antinutrients in Neolithic foods (see Dr. Cordain’s scientific paper on cereal grains here and Dr. Staffan Lindeberg’s research team paper on lectins and leptin resistance (PDFs).

[Note: Also see Stephan's series on leptin and lectins.]

Visceral fat – cytokines derived from visceral adipose tissue will cause insulin resistance.

Sleep deprivation – it may set off a hormonal cascade that may ultimately result in insulin resistance and Obesity.

I haven’t yet read Cordain’s book, but based on some of my regular reads (Whole Health Source, PaNu, Primal Body, Primal Mind, Mark’s Daily Apple), I see the themes above appearing again and again.

It’s just not a question of low-fat versus low-carb!