Fruits and vegetables have a surprising effect on the risk of depression: ScienceAlert

Increasing the amount of fruits and vegetables in your diet could reduce your risk of depression over time, according to a new comprehensive twin study including participants in the United States, Australia, Denmark and Sweden.

Twin studies are particularly useful to scientists because twins are genetically very similar. Any differences in health – such as symptoms of depression, in this case – are therefore more likely to be due to variables such as diet, exercise and living conditions.

Led by researchers at the University of New South Wales (UNSW) in Australia, the study analyzed data from a diet and mood survey of 3,483 people. All participants were aged 45 and over, with follow-up periods of up to 11 years.

“Twin pairs share 50 to 100 percent of their genetic makeup and, when raised together, they share the same family environment,” says geneticist Karen Mather, from UNSW.

“One advantage of the twin design is that it can help address the problem of undesirable factors, such as early life socioeconomic status, influencing outcomes.”

The team found a “modest” difference in depressive symptoms between those classified as having high fruit and vegetable intake (on average 2.1 and 2.0 average daily servings respectively) and those with low fruit and vegetable intake. vegetables (0.3 and 0.5 average daily servings respectively). ).

When comparing moderate consumption of vegetables and fruits to low consumption, the difference in depression is less pronounced for vegetable consumption and nonexistent for fruit consumption.

It’s also worth noting that most study participants still ate fewer vegetables and fruits than the generally recommended level: at least five servings total per day.

“We found that fruit and vegetable consumption in the two large Scandinavian studies was particularly low, with the average for both being less than half the World Health Organization’s recommended intake of at least five servings. per day,” explains lead author of the study, Nutrition. UNSW scientist Annabel Matison.

“We don’t know exactly what the reduction in depression scores would be if intakes were increased to recommended levels.”

Although the data is not detailed enough to prove cause and effect (physical activity, for example, was not included in the analysis), the relatively large sample size and use of twins works in favor of the study, suggesting that there is a link here. .

“The finding of a protective association between higher fruit and vegetable consumption and depressive symptoms in this study is consistent with most previous evidence,” the team writes in their published paper.

We know that fruits and vegetables are good for many aspects of our health. Previous studies have already highlighted links between diet and depression, as well as between depression and gut health (which may benefit from fewer ultra-processed foods).

The age of the study participants is also important: depressive disorders tend to peak in adults aged 55 to 75, and this research suggests that eating more fruits and vegetables is potentially an easy way to to remedy it.

“The results present another argument for increasing fruit and vegetable consumption among adults over 45,” says Matison.

The research was published in Scientific reports.