'Comparison with ancestral diets suggests dense acellular carbohydrates promote an inflammatory microbiota, and may be the primary dietary cause of leptin resistance and obesity' - Diabetes, Metabolic Syndrome and Obesity: Targets and Therapy 2012:5 175–189Click here for pdf
a few snippets from the article ...
"Whereas foods with living cells will have their low carbohydrate density “locked in” until their cell walls are breached by digestive processes, the chyme produced after consumption of acellular flour and sugar-based foods is thus suggested to have a higher carbohydrate concentration than almost anything the microbiota of the upper GI tract from mouth to small bowel would have encountered during our coevolution. This may stimulate differing bacterial species to prosper or be outcompeted, or increase some microbial metabolic pathways and waste products in preference to others. It is proposed that the effects of these enhanced carbohydrate concentrations will include a more inflammatory GI microbiota, initially causing leptin resistance, hence the greatly elevated leptin levels seen in Western populations when compared to those eating a wholly cellular diet."
"Once an inflammatory microbiota is in place, consumption of refined dietary fats and oils may effect a double hit by increasing the absorption of inflammatory PAMPs including LPS into the circulation (Figure 2), or stabilizing and preserving the inflammatory microbiota itself."
"Low-carbohydrate diets will reduce acellular carbohydrate consumption as a by-product of markedly reducing all carbohydrates. This is suggested to result in a larger reduction in the inflammatory nature of the GI microbiota, weight loss without conscious caloric restriction, and improved metabolic syndrome markers.86,88,106 However, low-carbohydrate diets retain some carbohydrates (usually less than 20–50 g per day), often with no regard to their density. This means what little carbohydrate is eaten may still lay the basis for an inflammatory microbiota, which is proposed to receive a second hit via additional energy for bacteria and increased LPS translocation from the elevated fat content that often accompanies a low-carbohydrate diet."
"Hence a grain-free whole-food diet would be predicted to restore the GI microbiota to the less inflammatory state that humans coevolved with."
"Westerners with higher insulin resistance might initially benefit from a low-carbohydrate form of Paleolithic-style eating. However, over time (and assuming no permanent diabetes-related damage) the resulting restoration of insulin sensitivity should mean a diet with a higher level of unrefined whole fruit and starchy root vegetables should be compatible with maintaining optimal metabolic health and stable healthy weight."
"The complexity of the microbiome and its interplay with the host is hard to overstate."
"A dietary pattern with carbohydrates exclusively from cellular low-density sources may remove the root cause of a range of our most prevalent diseases."