Eating a more fibre-rich diet may support mental wellbeing and overall health, according to new research from Adelaide University.
Dr Engida Yisma, Associate Professor Zohra Lassi and their team from the School of Public Health looked at the associations between dietary fibre intake and depressive symptoms before and during the COVID-19 pandemic.
Assessing data from more than 12,000 responses from the American National Health and Nutrition Examination Survey between 2017 and 2020, and 2021 and 2023, the study found that consuming more fibre could help reduce depressive symptoms.
“Depression became more common during the COVID-19 pandemic, affecting millions of people worldwide,” Dr Yisma said.
“Our research looked at whether people who eat more fibre-rich foods – such as fruits, vegetables, whole grains, and legumes – are less likely to experience symptoms of depression.
“We also examined whether this relationship changed during the COVID-19 pandemic.
“Finding simple and affordable ways to support mental health is important, and diet may be one of the factors that can help improve wellbeing.”
The findings have been published in the journal Clinical Nutrition ESPEN.
In Australia, adults are recommended to consume around 25 grams (women) to 30 grams (men) of fibre per day, according to NHMRC guidelines.
“Survey respondents’ dietary fibre intake decreased from 16.52 grams per day pre-pandemic to 15.95 grams per day during the pandemic,” Dr Yisma said.
“We also noted that depressive symptoms increased modestly from 8% pre-pandemic to 10% during the pandemic.”
For every additional five grams of energy-adjusted fibre intake people consumed, there was a 14% lower prevalence of depressive symptoms before the pandemic.
“During the pandemic, this protective effect became weaker overall, although it remained noticeable among women,” Associate Professor Lassi said.
“Our analysis also found a gender-specific pattern between energy-adjusted dietary fibre intake and depressive symptoms across the two time periods.
“This is consistent with the established gender disparities in depression, where women demonstrate higher lifetime prevalence and greater inflammatory sensitivity.”
Dr Yisma said eating more fibre-rich foods may help support mental wellbeing and overall health.
“More research is needed to understand exactly how fibre affects mental health and why the benefits may differ between men and women, especially during stressful periods such as a pandemic,” he said.