How milk nourishes the brain

Unveiling the surprising ways dairy foods influence mental health

By Cara Rosenbloom, RD

Anxiety, depression and other forms of mental illness affect about half of all Canadians by the time they reach age 40.  And it starts young — Canadians aged 15 to 24 are more likely to experience mental illness than other age group.  Researchers are increasingly looking at the impact of lifestyle factors – such as diet and physical activity – and their impact on mental health at all ages. 

It has increasingly been shown that a nutritious dietary pattern can improve mental health. Studies show that ultra-processed foods are detrimental to mental health, due to their absence of beneficial nutrients and high amount of salt, sugar, additives or preservatives. Diets filled with whole or minimally processed foods show better health outcomes.  

Researchers are interested in the link between mental health and dairy foods such as milk, cheese and yogurt. As minimally processed, nutrient-rich foods, studies increasingly show the value of dairy foods in brain health and mood. Here’s why dairy should be on your patients’ menu. 

Milk is a nutrient-rich food

Milk is a powerhouse of nutrients, boasting nine grams of protein per cup, plus an array of brain-supporting vitamins and minerals. Studies show that a higher intake of dairy, calcium and vitamin D are associated with protective effects on mental health.  

Studies show that getting enough calcium may help prevent depression.  Calcium is part of the pathway that leads to serotonin synthesis (serotonin plays a key role in regulating mood). 

Low vitamin D has also been linked with depression.  Vitamin D activates the gene expression of enzymes that help produce neurotransmitters such as dopamine and noradrenaline.  Low levels of these neurotransmitters have been linked to mood disorders, so getting enough vitamin D is important. 

Milk also contains a variety of B-vitamins, including vitamins B1, B2, B3, B6 and B12, riboflavin and niacin, which are vital for mental health and cognitive function.  B-vitamins act as co-factors in cellular processes related to regulating mood.

Benefits of dairy foods for children and young adults

A recent study of children aged 7-17 years looked at associations between dairy foods, depression and anxiety.  The researchers found that children who consumed dairy most often had lower scores for depression and anxiety.

Another recent study conducted among university-aged students found that those with a higher intake of dairy foods and calcium also had:

• Lower perceived stress 

• Higher positive mood scores

• Lower anxiety

• Higher resilience 

Milk intake tends to decline after early childhood, but the nutrients are important for brain health and mood control at all ages.  Dairy foods should be on the menu daily; one cup of milk contains 15 essential nutrients.

Dairy and the gut-brain axis

Emerging research supports the notion that the gut microbiome influences brain health and mood.  Known as the gut-brain axis, this communication system is important at all life stages. Changes in the microbiome can affect mood, and the gut-brain axis has been proposed as a link between diet quality and depression.

Fermented dairy foods such as yogurt and cheese provide probiotics that enrich the microbiome. A recent meta-analysis of eight studies on fermented dairy foods and depression noted a decreased risk of depression in people with higher intake of fermented yogurt and cheese.  Researchers speculate that probiotics in fermented dairy can modulate brain function via the gut-brain axis by influencing gut microbiota, decreasing inflammation, and influencing the production of neurochemicals.  

Dairy foods such as milk, cheese and yogurt contain a host of beneficial nutrients that support brain health and combat anxiety and depression. Dairy is an important part of the diet for Canadians of all ages. For more information, visit www.milk.org