People who eat fruit frequently are more likely to report higher positive mental well-being and are less likely to have symptoms of depression than those that don’t, according to new research from Aston University’s School of Health and Life Sciences in the UK.
The results, published in the scientific journal “British Journal of Nutrition”, suggest that the frequency with which we eat fruit is more important for our psychological health than the total amount that we consume during a typical week.
The team also found that people who eat salty snacks, such as potato chips, which have few nutrientsare more likely to have higher levels of anxiety.
The study surveyed 428 adults from across the UK and looked at the relationship between their consumption of fruit, vegetables and sweet and salty snacks, and their psychological health.
After taking into account demographic and lifestyle factors such as age, general health status and physical activity, the research found that both nutrient-dense fruit and nutrient-poor salty snacks appeared to be associated with psychological health. They also found that there was no direct relationship between vegetable consumption and psychological health.
According to the survey, the more often fruit was eaten, the lower the depression score and the higher the mental well-being score, regardless of the total amount of fruit intake.
People who frequently ate nutrient-poor salty foods (such as French fries) were more likely to suffer from “everyday mental lapses” (known as subjective cognitive failures) and to report lower mental well-being. A greater number of lapses was associated with a greater number of symptoms of anxiety, stress and depressionand with a lower mental well-being score.
In contrast, no relationship was observed between these everyday memory lapses and intake of fruit and vegetables or sweet snacks, suggesting a unique relationship between these nutrient-poor salty snacks, everyday mental lapses, and psychological health.
Some examples of these frustrating everyday mental lapses were forgetting where objects had been placed, forgetting the purpose of entering certain rooms, and being unable to retrieve names of acquaintances whose name was on the “tip of the tongue.”
“Very little is known about how diet can affect mental health and well-being, and although we don’t directly examine causality here, our results might suggest that frequent snacking on nutrient-poor, salty foods may increase everyday mental lapses, which in turn reduces psychological health”, explains lead author, doctoral student Nicola-Jayne Tuck.
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 have evaluated both frequency and quantity of intake.
Both fruits and vegetables are rich in antioxidants, fiber, and essential micronutrients that support optimal brain function, but these nutrients can be lost during cooking. As we are more likely to eat the fruit raw, this could explain its greater influence on our psychological health.