Can a Happier Diet Boost Your Mood? Scientists Say Flavonoid-Rich Foods May Be Key

As many experienced a notably wet February, with rainfall 19% above normal, a team of scientists in Northern Ireland suggests a surprisingly simple way to brighten outlooks: diet. Researchers led by Professor Aedín Cassidy at Queen’s University Belfast have found that increasing the intake of certain foods can lead to higher levels of happiness and optimism.

The research, conducted in collaboration with scientists from the Harvard T.H. Chan School of Public Health, focused on flavonoids – naturally occurring compounds found in plant foods. Flavonoids have been shown to cross the blood-brain barrier, influencing neurotransmitters and blood flow, potentially improving cognitive function. Previous studies have linked high flavonoid intake to longevity and a reduced risk of chronic diseases like dementia, diabetes, and heart disease [1].

The Link Between Flavonoids and Mood

“Ours is the first large study to highlight the positive connection between what we eat and our long-term happiness,” says Dr. Alysha Thompson, a colleague of Professor Cassidy’s at Queen’s and co-author of the study [1]. “It as well points to a positive cycle, in that eating well can boost happiness, and feeling happier may encourage healthier dietary habits.”

The team analyzed data from over 40,000 women aged 18 and older, tracking the impact of flavonoid intake on psychological wellbeing. Published in Clinical Nutrition, the results showed that consuming approximately three servings a day of flavonoid-rich foods – such as blueberries, strawberries, apples, or citrus fruits – resulted in a 3% to 16% sustained improvement in mood and optimism.

Maximizing Mood-Boosting Benefits

“There’s a definite dose response,” Thompson explains. “The more we eat of these flavonoid-rich foods, the better it is for our optimism.”

Professor Cassidy emphasizes the importance of diversity in flavonoid intake. “There are lots of different types of flavonoids, including the anthocyanins in berries, grapes, and aubergines, flavanols in tea and apples, flavonols in broccoli and kale,” she says [4]. “Some of them are good for blood pressure, others for lipid profile, others for the brain, so the more diversity of them in your diet over time, the better it will be for your health and mental wellbeing.”

Other Foods Linked to Improved Mood

A review by psychologists at the University of Reading also identified a positive link between certain foods and mood, including cocoa, berries, cherries, peppermint, walnuts, and green tea. Professor Anu Realo from the University of Warwick notes that caffeine, found in coffee and tea, can increase dopamine activity in the brain, leading to improved mood and alertness [2].

Consuming fruits and vegetables raw may also enhance their mental health benefits. Research from University College Dublin suggests that individuals prone to anxiety disorders often have reduced levels of choline in the brain, and these levels are lowest in the prefrontal cortex, a brain region crucial for thinking and emotional regulation. Richard Maddock, a psychiatrist and research professor at UCD, suggests that those with anxiety consider ensuring they consume adequate choline through their diet [3].