Eating too much fat and sugar in childhood can influence the microbiota for a long time, even in those who learn to eat healthier as they age.
Many of the microorganisms that strengthen the immune system, break down food, and help synthesize vitamins, live on and in our bodies, especially in our intestines. When the balance between beneficial and harmful microorganisms is disturbed, our immunity is reduced. Antibiotics, for example, can have this unbalancing effect because if they kill harmful bacteria, they also attack those that are beneficial to us. An unhealthy diet is also problematic in this regard, even in the (very) long term.
Initially, an American team (University of California) carried out experiments on mice. For three weeks, half ate a healthy, balanced diet, while the rest were fed a diet that was too high in fat and sugar. Then the rodents were split as follows: some had a racing wheel, others had no way to exercise. Three months later, the team examined the gut flora (microbiota) of all the mice and the impact on the number of beneficial bacteria became clear.
For example, the intestinal Muribaculum bacteria, involved in carbohydrate metabolism, was more present in mice with a healthy diet and a running wheel and less in mice who ate poorly, regardless of the amount of exercise they did. Diet alone therefore seems to play a key role.
“In our study, we studied mice, but the effect we observed is similar in humans,” said the coordinator of this research. “In children on a Western-style diet, which is too high in fat and sugar, the intestinal microbiota is affected for several years after puberty. You are therefore not only what you eat, but also what you ate as a child,” he concludes.