A new study led by scientists at the University of New South Wales confirms that eating fruit can help ward off depression – but eating vegetables does not.
Depression is a major public health concern: the global impact of depressive disorders is estimated to be over 50 million years of life lived with disability, making depression the largest contributor to non-fatal disease burden.
More than 80% of this burden is borne by low- and middle-income countries.
Compared with depression in younger adults, depression in older adults has a greater impact on physical and cognitive abilities and is associated with reduced quality of life and increased all-cause mortality.
A growing body of evidence suggests that diet, particularly increasing fruit and vegetable intake, may be important in reducing the risk of depression.
“The aim of this new study was to examine the relationship between fruit and vegetable consumption and depression in adults aged 45 and over,” said researcher Dr Annabel Mattison, from the University of New South Wales.
The study involved 7,801 non-depressed, community-dwelling adults from multiple sites across six continents, including the United States, Sweden, Brazil, Nigeria, Malaysia and Australia.
The results showed a beneficial association between higher fruit intake and a lower risk of depression over a nine-year period.
“This intriguing finding of a protective relationship between fruit consumption and risk of depression points to the need for greater emphasis on diet in healthcare,” said Dr Mattison.
The results suggested a benefit to vegetable consumption, but the benefit was not statistically significant.
“The reason we found a beneficial association with fruit consumption but not with vegetable consumption may be because fruits are typically consumed raw, whereas vegetables are typically consumed cooked, which may affect their nutritional value,” Dr Mattison said.
“Fruit and vegetable intake was self-reported via a comprehensive food frequency questionnaire, a short food questionnaire, or a dietary history.”
“Depressive symptoms were assessed using validated scales, and depression was defined by applying validated cut-offs.”
“We used Cox regression to examine the association between baseline fruit and vegetable intake and incident depression over 3- to 9-year follow-up periods.”
It has been suggested that the high antioxidant, dietary fiber, and vitamin content of fruits and vegetables may have beneficial effects on depression through a variety of mechanisms, including their role in inflammation, oxidative stress, and gut microbiota.
Because fruits and vegetables contain different nutrients, it is also possible that different types of fruits and vegetables may have different effects on depression risk.
The evidence that citrus fruits and green leafy vegetables reduce the risk of depression is particularly strong.
“Future studies that take into account consumption of different types of fruit and vegetables using standardized measures and focus on a larger number of older people, particularly in low- and middle-income countries, are definitely needed,” Professor Henry Brodaty, from the University of New South Wales, said.
“The expanding research currently being conducted into genes associated with dietary intake provides a promising avenue for influencing fruit and vegetable intake.”
“To better understand the association, the types of fruits and vegetables consumed also need to be taken into account, and studies need to be designed to be more comparable across cohorts.”
of study Published in Journal of Affective Disorders.
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Annabelle P. Mathison others2024. Associations between fruit and vegetable intake and incident depression in middle-aged and older adults in 10 diverse international longitudinal cohorts. Journal of Affective Disorders 359: 373-381; doi: 10.1016/j.jad.2024.05.096
Source: www.sci.news
