Fiber is essential for promoting satiety and blood sugar regulation, aiding digestion and supporting weight loss. The recommended daily intake of fiber is 25 grams for women and 35 grams for men. This equates to roughly 1/2 cup (75g) of high-fiber cereal, 1/2 cup (120g) beans, a pear, and 1/2 cup (100g) mixed veggies per day.
Now, there’s another great reason to add more fiber to your diet — it may also help you maintain a better mood. A higher intake of dietary fiber was associated with a lower risk of depression, according to a recent study.
Researchers analyzed the dietary habits of more than 5,800 women and found premenopausal women who consumed more fiber were less likely to be depressed than women who consumed lower levels of fiber. The study also showed every 1 gram increase of fiber intake per 1,000 calories was associated with a 5% decrease in the prevalence of depression.
“We think the most important finding of our study is dietary fiber intake was inversely associated with depression in premenopausal but not postmenopausal women,” says Dr. Yunsun Kim, study author and resident in the department of family medicine at Chung-Ang University Hospital in Seoul, South Korea. “We’d like to find modifiable factors that could prevent depression, especially in women who are more vulnerable to depression.”
The researchers didn’t find a connection between fiber intake and depression risk in postmenopausal women, and hormone levels may have been a factor. “Previous studies indicate there might be interaction between estrogen and gut microbiota,” Kim says. “Because post-menopausal women experience estrogen depletion, the decreased interaction between estrogen and the gut microbiota may be related to the insignificant association between dietary fiber intake and depression in post-menopausal women.”
For some time, researchers have known what happens in the gut may influence the brain. “The inverse relationship between dietary fiber intake and depression could be explained by the gut-brain interactions,” says Kim. “Changes in the gut microbiota composition may affect neurotransmission and various neuro-psychiatric phenomena in the brain.”
Certain fibers and carbs, called “oligosaccharides, are known as prebiotics, which feed the ‘good’ gut bacteria and promote a healthy gut microbiome,” explains Kelly Jones, RD.
“With an increasing prevalence of depression, which contributes to the global disease burden, we hope the findings of this study could form the basis of future investigations to determine the causal relationship between dietary fiber intake and depression,” adds Kim.
While more research is needed, it’s important to have a well-balanced diet that includes fiber-rich foods. “A nutrient-dense diet is associated with a healthier, more diverse gut microbiome, and that, in turn, is linked to brain health, [but] exactly how the two are connected is still unclear,” says Dr. Stephanie Faubion, medical director of the North American Menopause Society and director of the Mayo Clinic Center for Women’s Health in Jacksonville, Florida. “This study, in particular, found an association between fiber intake and mood, [but] it may also be that people with better mental health eat a healthier diet.”
For the time being, researchers advise people follow the daily fiber recommendations (regardless of menopausal status). Start by tracking your current fiber intake with an app like MyFitnessPal. To add more fiber to your diet, choose whole grains over refined grains whenever possible. Eat fruits and vegetables with every meal. Reach for nuts and seeds at snack time instead of processed snacks and add plant-based protein sources like beans and chickpeas to your menu. Increase your fiber intake slowly, and be sure to hydrate, so you minimize the risk of bloating and GI issues.
Discover hundreds of healthy high fiber recipes via “Recipe Discovery” in the MyFitnessPal app.