Because obesity increases risk for cognitive impairment and depression, being able to achieve and maintain an optimal body weight is an important mind-health strategy.

A study published in The International Journal of Obesity pointed to the nature of the gut microbiome, the bacterial cells living in the human gastrointestinal tract, as a determinant of whether a person will succeed in losing weight from a diet.

In a study of 62 overweight volunteers, Danish scientists assessed the ratio of two gut bacteria, Prevotella and Bacteroides. Half of the study volunteers followed a low-fat, high-fiber diet while the other half consumed a typical Danish diet.

Volunteers with a higher ratio of Prevotella to Baceteroides lost significantly more weight on the high-fiber diet than those with a lower ratio.

The results suggest that greater understanding of the gut microbiome may help people lose weight more efficiently.