Nutrition and Brain Health

Working in a hospital with a focus on addiction and mental health, the impact of nutrition on the overall brain and mental health is very apparent. It should be no surprise to learn that what you eat and drink has a direct effect on the health of your brain.

Like other body parts, the brain needs nutrition for optimal structure and function. The brain is largely made up of protein and fat and it needs a steady supply of vitamins and minerals to function properly. In turn, the health of your brain influences your overall mental health including moods.

While the brain only accounts for 2% of your body weight, it accounts for approximately 25% of your metabolic demands. Without a healthy diet, performance suffers.

The brain is made up of billions of nerve cells called neurons (we have about 86 billion of them, give or take). Each neuron has several points of contact with other neurons via synapses – about 100 trillion or so. These synapses are how the brain cells ‘talk’ to each other and are responsible for your feelings, consciousness, memory, mood and more.

Diet, and therefore nutrition, plays a central role in how well all of this works together. Here are 5 ways:

1. Structure

About 60% of the brain is fat. The quality of the fat in your diet will influence the quality of fat in your brain. Ideally about 15-20% of that fat would be omega-3s provided the diet supplies enough of them.

Regarding the omega-3 content in the brain, DHA makes up about 92% of the total.

PRO TIP: not all omega-3s are created equal. The plant form, alpha-linolenic acid (ALA) is not the same as EPA and DHA, which are the more biologically potent. Your brain is craving EPA and DHA.

Best sources of EPA and DHA

  • Any fish or seafood
  • Omega-3 fortified eggs
  • Supplements
    • Fish oil
    • Calamari (squid) oil

Algae oil

2. Fuel

Carbohydrate is digested/broken down to glucose, a sugar that our brains use for fuel. In fact, the brain uses about 20% of all the carbohydrate you eat. 

Good sources of carbohydrate are:

  • Fruit & starchy vegetables
  • Grains & grain products
  • Milk & yogurt
  • Legumes: chickpeas, lentils, dried beans and peas

Whole food sources of carbohydrate will also have other brain-loving nutrients like vitamins, minerals, and phytonutrients.

3. Protein

Dietary protein is broken down into amino acids, which are the very building blocks of neurotransmitters.

Sources of protein include:

  • Fish, meats, poultry
  • Eggs, cheese, milk
  • Legumes: chickpeas, lentils, dried beans and peas
  • Whole grains, nuts & seeds

4. Protection

The brain uses a lot of oxygen and glucose for energy production and it is exposed to pollutants and toxins from everyday living. Therefore it is very susceptible to damage but many dietary compounds provide protection, e.g. antioxidants and anti-inflammatory phytonutrients.

 For protection, think “P”; P for protection and P for plants. Any and all plant foods are good, not just those that have been heavily promoted such as green tea, goji berries, and pomegranate. Fruits, vegetables, whole grains, legumes, nuts, seeds, and even fresh and dried herbs and spices all count.

A standout phytonutrient for brain health is lutein. This carotenoid is specifically concentrated in the brain, again if there’s enough of it in the diet. Lutein helps to preserve cognitive function. Also, studies show that those with early dementia benefit from increasing their intake of lutein-rich foods where lutein can slow down the rate of cognitive decline.

 Good sources of lutein include:

  • Corn, avocado, green peas, broccoli
  • Brussels sprouts, dandelion
  • Egg yolk
  • Spinach, kale, swiss chard, collard, beet, turnip, and mustard greens

5. Co-factors

Your brain uses all vitamins and minerals to best its best. Poor quality diets are associated with greater risk for depression, worsening anxiety, and an increased risk for dementia. Some of the heavy hitters for brain health include the B vitamins including choline, vitamins C, D, and E, and the minerals magnesium, iodine, zinc and selenium.

 A couple of standout B vitamins are B1 or thiamin, which the brain needs a lot of to help it burn glucose for energy efficiently. B12, B6 and folate (B9) help to keep homocysteine levels low. Elevated homocysteine promotes inflammation, which drives depression and worsens anxiety.

Studies routinely show that most Canadians are missing the mark when it comes to meeting the recommended daily intake of vitamins and minerals. Foods first always; take a minimally processed, whole foods approach while keeping your intake of highly processed foods to a minimum. Round this out with a good quality, broad-spectrum multivitamin, and mineral supplement.


Doug Cook RD, MPH is a Registered Dietitian and Integrative & Functional Nutritionist. He uses a science-informed therapeutic approach on food, diet & supplements where appropriate. He is the coauthor of Nutrition for Canadians for Dummies (Wiley, 2008), The Complete Leaky Gut Health & Diet Book (Robert Rose 2015) and 175 Best Superfood Blender Recipes (Robert Rose, 2017). You can learn more about Doug by visiting his Facebook page, following him on Twitter, or by checking out his website www.dougcookrd.com

Photo by jesse orrico on Unsplash