The study authors note that mushrooms contain a variety of substances that may be beneficial to mental health, including anxiety-fighting compounds like vitamin B12, antioxidants, anti-inflammatory chemicals, and nerve growth factor. Because of this beneficial nutrient profile, they speculated that a higher intake of mushrooms may be tied to a lower risk for depression — and designed a study to find out of this was true. They used data from the National Health and Nutrition Examination Survey (NHANES) between 2005 and 2016, in which participants responded to questions about their diet over the past 24 hours on up to two different occasions. Depression scores were measured using a standardized questionnaire called the Patient Health Questionnaire.
To get cutting-edge diabetes news, strategies for blood glucose management, nutrition tips, healthy recipes, and more delivered straight to your inbox, sign up for our free newsletters!
Mushroom intake linked to lower depression
A total of 24,699 participants were included in the study, with an average age of 45.5 years. Mushrooms were consumed by 5.2% of participants, and 5.9% of participants had depression based on their questionnaire-based scores. Compared with participants who ate no mushrooms or had a low mushroom intake, those in the middle group — with a median intake of 4.9 grams of mushrooms per day — were 69% less likely to have depression. Participants with the greatest mushroom intake, though — a median intake of 19.6 grams per day — were only 9% less likely to have depression than those with the lowest mushroom intake, an insignificant difference compared to those with a medium intake. Overall, mushroom consumers were significantly less likely to have depression than those who didn’t consume them, but there was not a dose-dependent relationship in which a higher mushroom intake correlated with a lower depression risk.
The researchers wrote that their study had several limitations, including the fact that it didn’t distinguish between different mushroom types. Different varieties of mushrooms tend to contain widely varying levels of several compounds that may be key to the health benefits of mushrooms — including ergothioneine, an amino acid that acts as an antioxidant to protect against cell damage in the body, as noted in an article on the study at Medical Dialogues. Mushroom varieties that are highest in ergothioneine include King oyster, maitake, oyster, and shiitake, according to the American Society for Nutrition, while the varieties that are most common in grocery stores — white button, cremini, or portabella mushrooms — contain lower levels of ergothioneine. It isn’t known to what degree ergothioneine may be responsible for mental health benefits linked to eating mushrooms.
In the face of this uncertainty about what level of mushroom intake is beneficial, it may be best to aim for a moderate intake of two or three servings of mushrooms per week. This level of consumption, the American Society for Nutrition notes, has been linked to a lower risk for mild cognitive impairment in previous research — indicating that the beneficial compound in mushrooms may improve brain function in more areas than just emotional health.