Urine tests have revealed a biological marker linked to depression is common in otherwise healthy young people who eat a Western-style diet that is high in fat, sugar and processed foods.
A Macquarie University study of 169 adults aged 17 to 35 found those eating a Western-style diet were more likely to have lower levels of kynurenic acid (KA) – a small molecule important to a number of bodily functions – and report higher levels of depression than those eating diets rich in fresh fruit and vegetables.
Neuroscientist Dr Edwin Lim and neuropsychologist Dr Heather Francis, both Society for Mental Health Research Fellows, together with psychologist Professor Richard Stevenson, have published a paper on the findings of the study in the journal Frontiers in Nutrition.
“Western-style diets high in fat, sugar and processed foods were already known to increase the risk of depression, but this is the first time a biological link involving the kynurenine pathway has been established,” Lim says. “People from the group eating an unhealthy diet had lower levels of KA and more severe symptoms of depression. This indicates that KA may help to protect us against depression.”
