New study suggests higher daily dietary fiber intake is linked to lower risk for depression

Fiber intake may be linked with a reduced risk of depression, especially in premenopausal women, according to a new study published in the journal Menopause.

In this new study, involving more than 5,800 women of various ages, researchers specifically sought to investigate the relationship between dietary fiber intake and depression in women by menopause status. Dietary fiber is found mainly in fruit, vegetables, whole grains, and legumes.

The study confirmed an inverse association between dietary-fiber intake and depression in premenopausal women after adjusting for other variables, but no significant difference was documented in postmenopausal women.  

Research has suggested that estrogen depletion may play a role in explaining why postmenopausal women don't benefit as much from increased dietary fiber, because estrogen affects the balance of gut microorganisms found in premenopausal and postmenopausal women. The link between dietary fiber and depression may be partially explained by gut-brain interactions because it is theorized that changes in gut-microbiota composition may affect neurotransmission. Fiber improves the richness and diversity of gut microbiota, the researchers said.

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 several theories as to why this is the case. Changes in hormone levels in perimenopausal women have been linked to depression.

Due to the serious consequences and prevalence of depression, numerous studies have been undertaken to evaluate treatment options beyond the use of antidepressants. Lifestyle interventions, including diet, exercise, and mindfulness, may help to reduce the risk for depression.