Research shows that a diet for children has a lifelong effect

Eating too much fat and sugar as a child can change your microbiome for life, even if you learn to eat healthier later on, a new study in mice suggests.

The study by UC Riverside researchers is one of the first to show a significant decrease in the total number and diversity of gut bacteria in adult mice fed an unhealthy diet as a juvenile.

“We have studied mice, but the effect we observed is similar to that of children who follow a Western diet, are high in fat and sugar and that their gut microbiome is still affected up to six years after puberty,” explains the evolutionary physiologist Theodore Garland of UCR explains.

An article describing the study was recently published in the Journal of Experimental Biology.

The microbiome refers to all bacteria, as well as fungi, parasites and viruses that live on and in a human or animal. Most of these microorganisms are found in the gut, and most of them are helpful, boost the immune system, break down food, and aid in the synthesis of important vitamins.

In a healthy body there is a balance between pathogenic and beneficial organisms. However, if the balance is disrupted, either through the use of antibiotics, illness or unhealthy food, the body can become susceptible to illness.

In this study, Garland’s team looked for effects on the microbiome after dividing their mice into four groups: half got the standard, ‘healthy’ diet, half got the less healthy ‘Western’ diet, the other half with access to a running wheel to practice, and half without.

After three weeks on these diets, all mice were returned to a standard diet and no exercise, as mice are normally kept in a lab. After 14 weeks, the team examined the diversity and abundance of bacteria in the animals.

They found that the amount of bacteria such as muribaculum intestinal was significantly reduced in the Western diet group. This type of bacteria is involved in carbohydrate metabolism.

Analysis also showed that the gut bacteria are sensitive to the amount of exercise the mice received. Muribaculum bacteria increased in mice fed a standard diet and had access to a running wheel, and decreased in mice fed a high-fat diet, regardless of whether they exercised or not.

Researchers believe that this bacterial species, and the bacterial family to which it belongs, can influence the amount of energy available to the host. Research continues on other functions that this type of bacteria may have.

Another notable effect was the increase in a very similar bacterial species enriched after five weeks of treadmill training in a study by other researchers, suggesting that exercise alone can increase its presence.

Overall, the UCR researchers found that early life Western nutrition had more long-lasting effects on the microbiome than exercise in early life.

Garland’s team would like to repeat this experiment and take samples at different times to better understand when the changes in mouse microbiomes first occur and whether they extend into even later life stages.

Regardless of when the effects first occur, the researchers say it is significant that they were seen for so long after changing the diet and then again.

The takeaway, Garland said, is essentially, “You are not just what you eat, but also what you ate as a kid!”

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