Dietary fiber, found mainly in fruits, vegetables, and legumes, is commonly recommended as a vital part of the diet due to its link to risk reduction of a number of metabolic conditions, but new clinical evidence in a clinical trial published by the North American Menopause Society (NAMS) suggest that its digestive benefits may also play a role in mitigating the risk of depression, at least in premenopausal women, who undergo significant hormonal changes as part of the aging process.
 
“Depression is a common and serious mental health condition that not only affects a person’s ability to perform daily activities but can also lead to suicide. It’s estimated that more than 264 million people worldwide have depression, with numbers increasing over time. This debilitating condition is much more common in women, and there are a number of theories as to why this is the case. Changes in hormone levels in perimenopausal women have been linked to depression,” the authors said.
 
The new study involved more than 5,800 women of various ages, and was designed to investigate the relationship between dietary fiber intake and incidences of depression, while taking menopause status into account. Previous studies have established a link between dietary fiber intake and better mental health outcomes, but the present study is the first to do so specifically for women who’ve underwent menopause.
 
The study confirmed a significant inverse association between fiber intake and depression rates in premenopausal women, however, the relationship was not significant in women who had already underwent menopause, suggesting that estrogen depletion negates the apparent mental health benefits of healthy fiber intake. Estrogen is known to effect the gut microbial environment, and the link is at least partially explained by interactions taking place between neurotransmitters produced in the gut and the brain. Fiber improves the richness and diversity of gut bacteria.
 
“This study highlights an important link between dietary fiber intake and depression, but the direction of the association is unclear in this observational study, such that women with better mental health may have had a healthier diet and consumed more fiber, or a higher dietary fiber intake may have contributed to improved brain health by modulating the gut microbiome, or some combination. Nonetheless, it has never been more true that ‘you are what you eat,’ given that what we eat has a profound effect on the gut microbiome which appears to play a key role in health and disease,” Dr. Stephanie, Faubion, NAMS medical director, said.