So your reasoning is humans adapt to stuff therefore grains aren't unhealthy? Are you mentally disabled? There is tons of evidence to suggest that humans have not adapted sufficiently to grains enough to make them a healthy food. That humans adapt does not entail that humans have adapted full to grains, they are still harmful. Nobody is just taking it on faith that "humans have only been eating grains for a little while therefore they are BAD". We tend to feel the need to test these things empirically.
Loren Cordain, 2010
Currently there’s an epidemic of type 2 diabetes (T2D) worldwide, especially in Westernized countries. T2D is characterized by persistent elevated glucose levels due to disrupted insulin action or an alteration in pancreatic insulin production1.
It was estimated that 171 million people were suffering from T2D in 2001, with a total overall population prevalence of 6%. More alarming is the fact that in Caucasian adolescents 4% suffer from T2D and 25% are glucose intolerant1. However, T2D prevalence in hunter-gatherer societies is low2-6, and even nonexistent in the island of Kitava in Trobiand Islands in Papua New Guinea3.
Genetics does not seem to explain the difference, because when these populations are Westernized they suffer even more from diseases of civilization such as T2D, obesity, myocardial infarction and stroke among others7-10 than original Western populations. Furthermore, there’s evidence showing that hunter-gatherer populations can reverse T2D when they are resettled in their ancient habitat8, a fact that has been demonstrated in two recent clinical trials conducted on Western populations11, 12.
Insulin resistance seems to be one of the factors involved in T2D which is caused, by low-grade chronic inflammation13-15 among other factors. Interestingly, low-grade chronic inflammation is a hallmark16-19 in T2D patients.
Considering these factors, it seems plausible that the nutrition introduced with the agricultural revolution 10,000 years ago played an important role in the current diabetes epidemic in Westernized populations. Western foods are overload with antinutrients, namely lectins, saponins and gliadin, which may explain the great disparity between paleolithic and modern Western food when it comes to metabolic syndrome (a combination of medical disorders that increase the risk of developing cardiovascular disease and diabetes). There is evidence showing that antinutrients act as endocrine disrupting substances, promoting metabolic syndrome20. On the other hand, antinutrients may elicit their negative health effects through increased intestinal permeability21. However, scant evidence exists regarding the role of antinutrients in the aetiology of Western diseases.
Gliadin and increased intestinal permeability
One of the most studied foods in the recent years is wheat, which contains a protein called gliadin, and is part of the gluten protein family22. Gliadin increases gut permeability by means of Zonulin production (a protein that regulates in tight junctions between cells in the wall of the digestive tract) in the gut enterocytes (epithelial cells found in the small intestines and colon). Zonulin binds the CXCR3 chemokine receptor leading to intracellular signalling cascades, mediated by protein kinase C (PKC), which ultimately causes disruption of the tight junction proteins which maintain the gut barrier function, and lead to increased gut permeability23, 24.
In addition, when intestinal permeability is increased, gliadin - which is resistant to heat and digestive enzymes - is able to interact with gut associated lymphoid tissue (GALT) stimulating the innate immune system, leading to low-grade chronic inflammation22, 24. Several studies have demonstrated that gliadin induces the production of pro-inflammatory cytokines (a small protein released by cells that has a specific effect on the interactions between cells, communications between cells or the behavior of cells), independent of one’s genetic predisposition to celiac disease – which is virtually everyone23, 25, 26.
Lectins and increased gut permeability
Lectins are a family of glycoproteins (a complex protein containing a carbohydrate combined with a simple protein) found in the plant kingdom, including grains, legumes and solanacous plants (tomatoes, potatoes, eggplants and peppers)21, 27. Lectins also have the ability to bind sugar containing molecules. They were first studied for their ability to agglutinate (cause to adhere) red blood cells by binding to their cell membranes. Many lectins present in other foods are harmless, but some lectins found in grains, legumes and solanaceous plants have been shown to be harmful to human physiology28. Lectins are resistant to heat (unless cooked by pressure cooking)29 and digestive enzymes38, and therefore arrive intact when they reach the intestinal epithelium, passing through the intestinal barrier into peripheral circulation. Lectins are able to bind peripheral tissues, producing many deleterious health effects21. Furthermore, lectins disrupt intestinal barrier and immunological function when they bind surface glycans (a carbohydrate polymer containing simple sugars) on gut epithelial cells, causing cellular disruption and increasing gut permeability. Lectins also facilitate the growth of certain bacteria strains, stimulate T-cell proliferation, increase intercellular adhesion molecules (ICAM), stimulate production of pro-inflammatory cytokines (IL-1, TNF-alpha, etc.), and amplify HLA class II molecules expression, among other effects21.
Stabbing conventional wisdom in its face.
Anyone who wants to talk nutrition should PM me!