Current nutritional guidelines in terms of the effect on gut microbiota and human health considering the WHO and FAO recommendations

The purpose of this paper is to evaluate current nutritional guidelines of modern diets based on medical and nutrition facts and their effect on gut microbiota and health, considering current recommendations of world authorities such as FAO and WHO. For this purpose, the first part is devoted to the impact of microbiota on human health, and special attention is committed to the effect of fibre on gut microbiota. The second part is dedicated to the fundamental division of diets and the evaluation of concrete nutritional guidelines of modern diets into microbiota and health, followed by the recommendations of global authorities. Modern diets include diets from the point of view of medical science (e.g. Mediterranean), promoted by nutritionists and authorities (e.g. Nordic) and by social trends (e.g. vegan). The evaluation summarises that high-fibre diets have tremendous benefits on human health. Diets with fresh, local and naturally fermented food positively impact the gut microbiota, hence human health (agrarian diets). The results of the review show that the nutritional guidelines associated with the lowest mortality are the Mediterranean with the Atlantic or Nordic diet, which is in line with the recommendation of the world authorities (FAO, WHO, UN). The low-fibre western diet with highly processed foods with no or very low levels of live bacteria appears to be high-risk in terms of preventing civilisation diseases with a negative impact on gut microbiota, which is in line with current FAO and WHO guidelines.