APOE and Alzheimer disease: Interestingly, it has even been proposed that high-carbohydrate diets contribute to AD on the basis of meta-analyses that reveal lower frequency of ApoE4 in populations with long-standing historic exposure to agriculture, such as the Turks or Mayans (ApoE4 allele frequency of 0.079–0.089), as compared to hunter-gatherers such as the Papuans or Inuits (0.214–0.368) [72].