Can Eating More Fruit Reduce Depression?

Some research claims are a bit simplistic.

Key points:

• New research suggests that increasing the frequency of eating fruit can improve wellbeing and reduce depression.
• But it isn’t a clear case of cause and effect because the researchers didn’t check that.
• Such research findings don’t take sufficient account of other relevant factors.
• So be careful what you believe.

Can we improve our mental wellbeing simply by upping how often we reach for the fruit bowl? That is what psychologists from the College of Health and Life Sciences at Aston University are suggesting. They surveyed 428 adults from across the UK to establish any relationship between their psychological health and their consumption of fruit, vegetables and sweet and savoury snacks.

According to their findings, the more times people ate fruit, the better their mental wellbeing and the lower their experience of depression, whereas those who tended to grab nutrient-poor savoury snacks, such as crisps, had lower mental wellbeing and more “everyday mental lapses” (such as forgetting where they had put things), which are linked with anxiety, stress and depression.

Tellingly, at least to the researchers, there was no direct link between eating vegetables and mental wellbeing, and no link between mental lapses and either fruit or vegetable intake, or, curiously, intake of sweet (as opposed to savoury) snacks.

Lead author PhD student Nicola-Jayne Tuck reports enthusiastically, “Our findings could suggest that frequently snacking on nutrient-poor savoury foods may increase everyday mental lapses, which in turn reduces psychological health.

“Other studies have found an association between fruit and vegetables and mental health, but few have looked at fruit and vegetables separately – and even fewer evaluate both frequency and quantity of intake.

“Both fruit and vegetables are rich in antioxidants, fibre and essential micronutrients which promote optimal brain function, but these nutrients can be lost during cooking. As we are more likely to eat fruit raw, this could potentially explain its stronger influence on our psychological health.

“It is possible that changing what we snack on could be a really simple and easy way to improve our mental wellbeing.”¹

Hmmm. While it is the kind of study that gets pounced on by news media – eat fruit to avoid depression! – I think there should be alarm bells ringing here. Why should sweet snacks (like custard pies or chocolate biscuits perhaps?) keep us immune from mental lapses, as they are surely as nutrient poor as the savoury variety? When findings don’t make sense, it usually means that the statistics they are based on are insignificant – in the lay sense of the word.

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