Correlations between diet, gut microbiome and health are analyzed in the largest international research project to date. The scientific study, published in Nature Medicine, analyzes the impact of foods on host microorganism communities. It clearly notes the connection, pointing the way to prevent metabolic diseases. (1)
The research, Predict(Personalized Responses to Dietary Composition Trial), was initiated in 2018 by British epidemiologist Tim Spector on a sample of 1,098 adult individuals in the U.S. and Britain, including more than a hundred twins (identical and non-identical). Analyzing 1,203 microorganisms, in their intestinal bacterial communities.
Same genes, different microbiome
The researchers compared the diet, microbiome and body mass index of the study participants. They monitored pre- and postprandial blood levels of sugars, hormones, cholesterol, and inflammation levels. Noting sleep and exercise habits.
Genetics, unlike what has been estimated so far, was found to be irrelevant to the composition of the microbiome. In fact, the comparative analysis showed that identical twins, among the participants, shared only 34 percent of the same gut microbes, compared with the typical 30 percent among people with no kinship.
‘Good’ bacteria with the right foods
Instead, the determining factor for microbiome characterization and metabolic health is confirmed to be food. Through analysis of food diaries, the prevalence of health-allied bacteria in the microbiota of those who regularly consume vegetables and nuts (spinach, broccoli, tomatoes, seeds, nuts, etc.) emerges. The fiber in which such foods are rich, among other things, has also been found to be beneficial in the significant reduction (-30%) in all-cause mortality. Animal proteins contained in natural or minimally processed foods, such as fish and whole yogurt, also promote the development of ‘good’ bacteria.
The presence of these bacteria is associated with both better glycemic control and lower levels of visceral fat. Namely, fat that accumulates around the internal organs and increases the risk of heart disease (the leading cause of mortality worldwide, as noted). The beneficial gut bacteria then help reduce inflammation levels as well as blood fat levels.
Junk food and microbiome damage
Habitual consumption of ultra-processed foods with too much sugar and/or salt, saturated fats and additives is conversely associated with higher concentrations of ‘bad’ bacteria in the gut microbiome. Not surprisingly, junk food has already been shown to be able to unhinge the immune system, which is in fact regulated by the microbiota. (2)
Recognizing junk food is easy, as we have seen. Snacks and sweets, sugary drinks, ready meals and products made with substances unknown to the home kitchen and with poor nutritional profiles (HFSS, High in Fats, Sugar and Sodium).
From microbiome analysis to prevention
Predict, nomen omen
, suggests how examining the microbiome could also help understand individual exposure to the risk of developing metabolic diseases. On this basis, nutritionists could develop customized diets with specific preventive purposes.
Further evidence from the study is the variety of responses to identical foods in individuals. Different responses in both microbiome formation and metabolic response.
Prevention is always rooted in a varied and balanced diet. Better if based on organic foods, which are also healthier for microbiome and immune system as seen.
Marta Strinati and Dario Dongo
Cover image, see note 3
Notes
(1) Asnicar, F., Berry, S.E., Valdes, A.M. et al. Microbiome connections with host metabolism and habitual diet from 1,098 deeply phenotyped individuals. Nat Med (2021). https://doi.org/10.1038/s41591-020-01183-8
(2) Anette Christ, Patrick Günther, Mario A.R. Lauterbach , Peter Duewell, Debjani Biswas, Karin Pelka, Claus J. Scholz, Marije Oosting, Kristian Haendler, Kevin Baßler, Kathrin Klee, Jonas Schulte-Schrepping, Thomas Ulas, Simone J.C.F.M. Moorlag, Vinod Kumar, Min Hi Park, Leo A.B. Joosten, Laszlo A. Groh, Niels P. Riksen, Terje Espevik, Andreas Schlitzer, Yang Li, Michael L. Fitzgerald, Mihai G. Netea, Joachim L. Schultze und Eicke Latz. Western diet triggers NLRP3-dependent innate immune reprogramming’. Cell, 11.1.2018, doi: 10.1016/j.cell.2017.12.013
(3) Justin L. Sonnenburg, Erica D. Sonnenburg (2019). Vulnerability of the industrialized microbiota. Science. 25 Oct 2019. Vol. 366, Issue 6464, eaaw9255 doi: 10.1126/science.aaw9255
Professional journalist since January 1995, he has worked for newspapers (Il Messaggero, Paese Sera, La Stampa) and periodicals (NumeroUno, Il Salvagente). She is the author of journalistic surveys on food, she has published the book "Reading labels to know what we eat".
Dario Dongo, lawyer and journalist, PhD in international food law, founder of WIISE (FARE - GIFT - Food Times) and Égalité.
