Nutritionists have long touted the benefits of high-fiber foods for their ability to help us feel full and satiated, and in turn, better regulate our caloric intake.
According to the Mayo Clinic, a diet filled with fiber-rich foods—like pears, bananas, whole grains, lentils and beans—may provide health benefits like a decreased risk for heart disease, diabetes and obesity. It’s recommended that women eat 21 to 25 grams of fiber a day and men 30 to 38 grams a day.
So yes, there are a few health benefits associated with adequate fiber intake, but like many nutritionists and weight loss experts suggest, can it actually help someone lose weight?
Well, new research shows that while it’s not a “magic bullet,” it likely can play an important role in the process.
The study examined two groups of rats: both were fed a high-fat, high-sugar diet and were granted unlimited access to such foods, but one group was given a prebiotic fiber supplement called oligofructose, which is naturally occurring in foods like onions and bananas.
The scientists found that even though they had unlimited access to fatty and sugary foods, the rats who were given the fiber supplement gained about one third less weight compared to the rats who weren’t fed the supplement.
These results were produced in both rats that were genetically prone to obesity and rats that were resistant (or relatively leaner). The study’s lead author, Nina Cluny, Ph.D., a postdoctoral fellow in the Cumming School of Medicine's Hotchkiss Brain Institute and the Department of Physiology and Pharmacology, said that this was the most profound aspect of the findings.
The researchers suspect that oligofructose may help to protect against weight gain due to the way it interacts with microbes in our gut, as well as gut hormones that control our food intake.
Cluny explained that the results from this study revealed that the microbes in the guts of the obese rats who were given the fiber supplement became more similar to the microbes in the guts of the leaner mice. Additionally, they found that a hormone in the gut that controls satiety, or the feeling of being full, was increased by the oligofructose.
Although the study was performed on mice, the researchers are confident that fiber can help humans with weight loss and weight maintenance.
However, they did note that it doesn’t directly contribute to weight loss and shouldn’t be used as an alternative to exercise and diet, but more so a tool that can help aid those efforts.