Nutrition and the brain

[icon name=”user” class=”” unprefixed_class=””]  By Joanne P. Shelby-Klein BSN RN

Olive Oil DropFood, it has been recognized for many years as a source of energy and building blocks for the body as well its role in preventing and treating diseases. In recent years, there has been a focus on how food affects the brain and mental function. According to the American Psychiatric Association annual meeting, a diet that is healthier for the brain helps improve people’s focus, increases energy levels and self-confidence, especially when combined with exercise. What people eat and how they eat it is influenced by people’s beliefs, value systems, culture, religious beliefs and society as a whole. As new information is learned about how food affects the brain and mental health, it may challenge how the influencing factors shape eating patterns. Taking into consideration the factors that influence what people eat and helping them to adjust within the limits of these factors is the job of healthcare providers and requires open, honest communication between provider and patient.


Eat the rainbow is a clever saying to remember to eat foods with a variety of colors and packed with healthy nutrients. Foods that have bold bright colors such as red, purple, blue, yellow and green (think the colors of a rainbow) tend to be loaded with valuable vitamins and nutrients. By working these bright colored vibrant foods into your diet, even gradually, will increase the amount of vitamins available for the body, especially the brain. These colorful foods taste good, are often lower in calories and fat and help you not feel as hungry. These foods can also help your brain to function better.


  • Seafood: Most seafood is packed with brain healthy fatty acids such as Omega-3 fatty acids. Salmon, trout, mackerel and other oily, cold water fish are good choices. In 2012 it was reported that two servings a week can significantly decrease the risk for a stroke and can slightly impact the risk of psychotic symptoms. Mussels, oysters and clams are rich in Vitamin B12 and Zinc. Seafood is also a source of Vitamin D, Iodine, Iron and Chromium.
  • Green Leafy Vegetables: Green leafy Vegetables form a great base for healthy brain food. They contain fiber, (good for intestinal health and regular bowel movements), folate, magnesium, vitamin K, vitamin A, flavonols and calcium. Kale, mustard greens and bok choy are good examples. Many people complain about the taste of the foods. They can be made more tasty and tolerable by sautéing in olive oil and garlic or preparing them in a smoothie. They can even be baked into a chip for healthy snacking.
  • Nuts: Nuts are an underrated food that is loaded with nutrients. They help a person feel fuller longer and aid the body in absorbing important fat soluble nutrients. They contain healthy monounsaturated fats, fiber, and important minerals iron, manganese, selenium, as well as protein and vitamin E. Nuts are believed to be a good alternative to red meat as a source of protein.
  • Legumes: Legumes of beans, like nuts are a good alternate source of protein and nutrients. Beans contain anti-oxidants, protein, folate and iron.
  • Fruits: A Nurses Health Study reported in 2012, that flavanones and lycopene found in fruits had a 19% decrease in the risk for strokes in women. Berries and other fruits and vegetables with dark pigments may preserve brain health such as memory and thinking. Fruits also contain vitamin C, some vitamin E, Flavonoids and some Omega -3 fatty acids.


Flavonoids come from plant pigments and provide benefits to cell health and cell signal pathways. They contain powerful antioxidants, (substances that help prevent oxygen from destroying the food), that help with preventing heart disease, promote anti-cancer activities and provide overall good health. Flavonoids are found in fruits, vegetables, tea and even wine. Cocoa, beans and the gingko biloba tree are also rich in flavonoids. Studies have shown that people who eat dark chocolate have improved blood pressure control and a decreased risk for stroke.

According to the American Journal of Clinical Nutrition, Flavonoids have different beneficial effects on the body.

  • One of the largest benefits is working with the circulatory and vascular system to decrease the risk of death from cardiovascular disease and has helped with decreasing dementia.
  • Flavonoids also have anti-inflammatory effects. They work by blocking certain enzyme releases so that the anti-inflammatory response is blocked.
  • Flavonoids can have anti-tumor effects, although how it occurs and why it occurs is still being studied.
  • Flavonoids can also have an anti-clotting effect on the blood by preventing platelets from clumping together to form blood clots.

One thing that is known is that foods high in flavonoids need to be a part of a good healthy diet.


Omega-3 Fatty Acids are an important part of a healthy diet, so important they are called essential. They cannot be produced by the body but must be taken from foods. They make up a major part of the cell membranes. They also help make the regulating hormones that work with blood clotting, movement of the artery walls to keep the blood moving and help with regulation of genetic functions. Combined with other nutrient rich foods, Omega-3 fatty acids can help the brain, the heart and mental health be improved.


Poor nutrition and its effects can often be seen in physical illness. The connection between poor nutrition and mental health disorders such as depression is not as obvious. Depression is often viewed as an emotional and biochemical issue and not considered to be related to the eating habits and nutrition of the person. When looking at when depression starts and how severe it affects the person, it is important to look for food and eating patterns that are very similar to what happens when the person is diagnosed with depression. Many times people will have a very poor appetite, skip eating meals or may only want to eat sweet foods. People who are depressed show serious symptoms of sadness and anxiety, no desire to eat and a loss of interest in activities previously enjoyed.

People who are depressed often show a severe lack of many essential vitamins, minerals, omega-3 fatty acids and some amino acids, often times because they have lost their desire to eat or make poor food choices. Studies were conducted to look at the connection between the lack of these important nutrients and the severity of depression. The studies have shown that by looking at people with depressions diet, a pattern and similarities are observed. Depressed people tend to make poor food choices and often select foods that make depression worse. Studies are looking specifically at the role Omega-3 fatty acids play in treating depression as well as other nutrients. The results are still inconclusive and studies are ongoing. It is believed that the omega-3 fatty acids can help maintain and increase brain structures as well as preserve brain function by helping to control and modulate neuron signals and decreasing inflammation that happens during depression. It is also believed that by increasing omega-3 fatty acids in the diet, including the use of supplements, may help in the prevention and treatment of depression.

The B-complex vitamins have also been shown to affect mood and depression. The Neuropsychobiology Journal reported a study that showed supplementing the B-Vitamins up to 10 times the daily recommended intake improved mood in both men and women.

Studies have shown that depressed patients have a 25% lower folate level in their blood. One study reported that 500 micrograms of folic acid helps to increase the effectiveness of anti-depression medications. It has also been shown that symptoms of depression can be related to a folate deficiency. However, there is no clear evidence of what happens first, poor nutrition and folate deficiency causes depression or depression causes poor appetite, poor nutrition and the folate deficiency. This area requires additional research.

Other nutrients that have an impact on mood and depression include:

  • Iodine helps energy metabolism in the brain cells and works through the thyroid hormone to keep the brain healthy.
  • Iron is an important part of red blood cell formation that helps carry oxygen to all parts of the body, especially the brain. A deficiency of iron can cause people to feel tired, depressed and apathetic and may play a role in the start of depression.
  • Selenium is known as an essential trace element that is found in soil. When there is a selenium deficiency, the brain tends to hold on to it more so than other parts of the body. Five studies have shown that a poorer mood was related to a low intake of selenium or a selenium deficiency.
  • Zinc levels have been shown in five clinical studies to be lower in people who are depressed. Zinc can also play a role in how effective antidepressant medication is.


All studies conducted to date point to yes. Dementia is defined as a mental health condition that is common in the elderly. The brains structure changes in such a way that memory, ability to function in activities of daily living and behavior/mood changes are seen. Physical changes to the brain occur including an accumulation of proteins in the brain tissues and loss of neurons in the brain. People with type 2 diabetes, obesity and heart disease are at risk for developing dementia. These diseases also have a strong relationship to poor nutritional and dietary habits throughout life. Some studies suggest that foods containing omega-3 fatty acids and antioxidants can help with the prevention of dementia. There have also been studies conducted on Vitamin B-12, Folate and Vitamin D.

Body weight can give healthcare providers insight into a person’s nutritional intake. People who are overweight or considered obese may have an imbalance of energy output and poor food intake. Poor nutritional intake may be a risk factor for dementia. A study of 6583 people identified body center obesity as a risk factor for dementia. People who have larger abdominal measurements and a higher body mass index were 3.6 times more likely to get dementia.

A 2013 report from the National Health and Medical Research Council contained dietary guidelines that included increasing fish consumption. They reported that people who ate fish on a regular basis had a lower risk for diseases such as stroke and dementia. There has also been a theory that vitamin C and vitamin E could counteract damage to the neurons. The studies on this theory are inconclusive.

Another nutritional theory describing a way to decrease the risk of dementia believes that a diet high in fruits, vegetables, legumes or beans, accompanied by a moderate amount of fish and limited amounts of saturated fats and dairy products. The benefit of this type of diet is it contains the nutrients needed for good brain health such as folate, omega-3 fatty acids, vitamin B-12 and Vitamin E. While the research remains inconclusive on this type of diet, it does offer a measure of protection for memory and thinking and could be tried before memory impairment occurs.


Making healthy food choices and getting adequate nutrition is one part of taking care of your brain, mental health and mood. There are other things you can do including:

  • Keep your blood pressure, blood sugars and cholesterol levels in the acceptable ranges for each.
  • Stop smoking and avoid second hand smoke whenever possible.
  • Exercising or taking a brisk walk at least three times a week will help lower the risk for dementia and depression.

Supplements can also be taken to help with memory and concentration. Many supplements are untested and have little evidence to show if they work and what effects they have on the body. This is an area where evidenced based research is needed. It is recommended that you talk with a healthcare provider to see what supplements would be recommended for you before you start anything. It is also important that you talk to your health care provider before making changes in your diet and exercise program to make sure that the changes you make will work with any medical conditions you may have.


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