The study was performed on mice, who were separated into four groups: Half were given a high-fat, high-sugar diet; half given a standard healthy diet; half given access to a running wheel; and half given no access to a running wheel. After three weeks, all mice were returned to a standard diet with no exercise, which a press release states is how mice are normally kept in a laboratory.
At the 14-week mark, the team examined the animals’ microbiomes, and discovered that the quantity of a bacteria involved in carbohydrate metabolism was significantly reduced in the group fed the unhealthy diet. That type of bacteria,Muribaculum intestinale,was increased in mice fed a standard diet who had access to a running wheel, but decreased in mice fed a high-fat diet whether they exercised or not.
Related: Vitamin D Levels During Pregnancy Linked with Child’s IQ #NaturallyInformed Keynote Educates on Importance of Omega-3s for Cognitive Health Study Links Fiber Intake with Lower Rates of DepressionResearchers believe thatM. intestinalemay influence the amount of energy available to the host.
"We studied mice, but the effect we observed is equivalent to kids having a Western diet, high in fat and sugar and their gut microbiome still being affected up to six years after puberty," explained UCR evolutionary physiologist Theodore Garland in the press release. He and his team are looking to repeat the experiment, taking samples at additional points in the study to determine when these microbiome changes first appear and how far they extend—but the researchers note that it is significant that the changes extend as far as they do. “You are not only what you eat,” Garland concludes, “but what you ate as a child.”