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Impact of diet in shaping gut microbiota

The influence of diet on human microbiome
Impact of diets and shaping gut microbiota. Is the diet that important? An excellent example of how diet influences the microbiome was illustrated by a study of Paolo Leonetti and his team. What they did was to compare the gut microbiota composition between African children within a rural area in Burkina Faso and European children from Italy. As you can guess, African children still follow a traditional diet rich in fibres and vegetables, while Europeans have adapted to a Western diet in which the content of meat products and fats is high.
Research has found big differences in the bacterial colonisation in the gut among these two populations of children. The bacteria of the phylum Firmicutes were twice abundant in the EU children in contrast to the African, who harboured more bacteria of the phylum Bacteroidetes. Interestingly, other researchers had previously pinpointed
the value of the Firmicutes:Bacteroidetes ratio, as they found it to be higher in obese and overweight subjects. In this case, and compared to the African children,
the F:B ratio was higher in European children, showing the importance that these microbial changes might have for metabolic health. Moreover, in the children from Africa, the exposure to the large variety of environmental microbes associated with a high-fibre diet could increase the potentially beneficial bacteria, enriching the microbiome and its diversity. In contrast, the reduction in microbial richness is possibly one of the undesirable effects of globalisation on our diets that bring high-energetic food which are deprived of certain nutrients and fibres.
As was described in Burkina Faso children, differences in the bacterial diversity in the gut microbiota were also found between the members of the tribe called Hadza, located in Tanzania, and Italian subjects. The Hadza tribe had higher microbial richness and biodiversity than the people from Italy. However, the members of the Hadza tribe presented more genera of bacteria related to the ability to digest and extract valuable nutrients from fibrous plant foods. A curious fact that researchers found was that within the members of the tribe called Hadza, there were some differences in the gut microbiota between women and men, explained by the different daily tasks.
While women selectively forage for tubers and plant foods and spend a great deal of time in camp with children and family members, men are highly mobile foragers and often range far from the central campsite to obtain game meat and honey.
A third study drew to similar conclusions when comparing the gut microbiota of hunter-gatherer, traditional agriculturist communities versus the microbiota from an industrialised environment. Specifically, scientists analysed the microbiota of subjects from the tribe Matsés living in the Amazon rainforest and from the Tunapuco population from Peru. And they compared these with people living in Norman, a city in the United States. The subjects from the Amazonian and Peruvian communities presented low consumption of processed foods, like canned vegetables, bread, or prepackaged meals. Instead they kept a more rural diet, based on local agricultural products and hunted animals.
Interestingly, both Matsés and Tunapuco people showed enrichment in the genus called Treponema, which is related to carbohydrates metabolism, and that was missing in the North American subjects.
The expansion of the Western diet and similar dietary patterns are associated with higher intake of foods rich in fat, protein, and sugar, together with reduced intake of fibres, which are one of the reasons for the increase in the incidence of non-infectious intestinal diseases. Instead, traditional diets, like that followed by the tribes or communities included in the studies presented, are based on a high abundance of fermentable fibre that boosts the growth of beneficial bacteria with protective effects.
The diet is one key element that impacts health, and these effects partly depend on the microbiota. So remember, what you eat and how you eat plays a massive impact on gut microbiota. Here you have seen the importance of the type of dietary habits in the microbiota and the role that it plays to preserve its diversity and to prevent further problems. But do how each food compound influences your intestinal ecosystem?

Probably you know already that food and diet can largely affect the human microbiota and microbiome. In this video we introduce some studies which clearly demonstrate that the food we eat can really shape and modulate the gut microbiota and microbiome. For instance agrarian diet and Western diet selectively promote specific groups of microorganisms.

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The Human Microbiome

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