Thursday, July 7, 2011

Hunter-Gatherers and Cholesterol

Paul Jaminet on Loren Cordain:

"I thought I’d wrap up the hunter-gatherer cholesterol series by looking at some tropical populations outside Africa. These peoples may help us evaluate the merit of several explanations that have been put forth for variations in serum cholesterol:

 
  • Genetic differences. Africans tend to have lower cholesterol than non-Africans, wherever they live. Is the difference genetic? Chris Masterjohn believes genetic differences might account for up to a 30 mg/dl difference in TC. Emily Deans suggests LDL receptor variants are the most important alleles.
  • Dietary differences such as fat intake. For decades it was said that higher fat diets produce higher TC, and this was the favored explanation for variations in serum cholesterol. However, when these ideas were tested in clinical trials, diet-induced changes in TC were inconsistent.
  • Infectious disease burden. Eukaryotic pathogens such as protozoa, worms, and fungi – ie, pathogens that have mitochondria and therefore can metabolize fat and ketones – are often able to take up human lipoproteins from blood and use their fats and cholesterol for their own purposes. This tends to lead to low TC in people with a high burden of parasites. Is parasite burden the key to hunter-gatherer cholesterol levels?

 
"We started this detour (see Did Hunter-Gatherers Have Low Serum Cholesterol?, June 28, 2011) to evaluate the claims of S. Boyd Eaton, Loren Cordain, and collaborators [...]. Their papers tended to promote the following syllogism:
  1. Diet determines TC.
  2. Low TC is healthy.
  3. Hunter-gatherers had low TC.
  4. Therefore, hunter-gatherer diets are healthy.

"So to conclude today’s post, I’ll review: Which of these four theses is supported by the data?"
Read the whole thing.