The link between healthy eating and mental health

It might be surprising to know that there is a connection between mental health and nutrition. Research linking the two is growing at a rapid pace. In one survey, almost two-thirds of those interviewed who did not report daily mental health concerns said that they ate fresh fruit or drank fruit juice every day, compared with fewer than half of those who did report daily mental health problems.

The findings were similar for fresh vegetables and salad.

In addition, participants who complained of mental health issues were more likely to consume unhealthy foods, such as sugar-sweetened beverages, processed foods, snacks, and high-fat fast foods from take-out restaurants.

While professional treatment of mental illness is essential, making dietary changes which can improve mood should be an integral part of the treatment plan. A balanced mood and feeling of wellbeing depend on a diet that provides adequate amounts of complex carbohydrates, healthy fats, proteins, vitamins and minerals and water. There should also be a limited consumption of foods and beverages containing high sugar content.

How nutrients in foods can affect mental health

Carbohydrates: The primary source of energy for the brain is glucose, which comes from carbohydrates. There are two types of carbohydrates — simple and complex. Simple carbohydrates, such as sugar-sweetened beverages and white bread and rice, provide a quick jolt of energy causing a spike in sugar in the blood. They offer little in the way of nutrients but also exacerbate low mood. The effect of an excessive intake of sugary beverages and foods on the brain has been shown to be similar to that of drug abuse.

People who consume too much sugar may experience fatigue, irritability, dizziness, insomnia, poor concentration and forgetfulness. Depression and crying spells are also common.

By contrast, complex carbohydrates release glucose slowly providing a steady source of fuel for the brain and B vitamins for the body. Examples of healthy complex carbohydrates include whole-wheat products, oats, wild rice, barley, beans and soy.

Some complex carbohydrates from leafy greens — spinach, romaine, turnip and mustard greens, and broccoli, for example — are also high in folic acid. Folic acid, or folate, is a B vitamin that supports the function of the nervous system. It aids in the production of neurotransmitters or chemicals that are used by nerves to send signals throughout the body. Deficiencies in folate as well as other B vitamins have been linked to higher rates of depression, fatigue and insomnia.

Broccoli also contains selenium, a trace mineral that plays an important role in the immune system functioning, reproduction and thyroid hormone metabolism. Some studies suggest that low levels of selenium contribute to depression.

Protein: Proteins help maintain our skin, organ, muscle and immune function. Next to carbohydrates, protein is the most abundant substance in the body. The amino acid tryptophan, a building block of protein, influences mood by producing the neurotransmitter serotonin, which is sometimes called nature’s Prozac. Low levels of serotonin is associated with depression.

Kathy Cunningham, M.Ed., R.D., L.D.

Lean protein sources, including fish, turkey, chicken, eggs and beans, or a meat substitute such as textured vegetable protein, help keep serotonin levels balanced. Protein and carbohydrates team up to improve mental health. To increase the effectiveness of protein, complex carbohydrates can actually facilitate the entry of tryptophan into the brain, thus reducing the symptoms of depression and anxiety and improving overall cognitive function.

Fish and healthy oils: There is growing evidence to support the saying “fish is brain food.” Studies have found that foods high in omega-3 fatty acids, such as wild cold water fish (e.g., salmon, herring, sardines and mackerel), seaweed and walnuts, have been shown to reduce symptoms of schizophrenia, depression, attention deficit hyperactivity disorder and other mental disorders. This is likely due to the effect omega-3 has on the production of brain chemicals such as dopamine and serotonin. Both these chemicals are responsible for mood. Omega-3 also boosts learning and memory.

New evidence published in the Journal of the American Medical Association Internal Medicine shows that balancing carbohydrates, protein, fish and healthy oils in a Mediterranean-style diet can help to protect the brain and improve cognitive function.

Fluid intake: Here’s another reason to drink plenty of water every day. We think of the brain as billions of white cells and gray cells, but brain tissue is also 85 percent water. Not drinking enough fluid has significant implications for mental health. Dehydration reduces the generation of energy in the brain. The early effects of even mild dehydration can affect our feelings and behavior. Some studies link depression to dehydration.

Other studies show that water is a great “anxiety quencher.” Dehydration can actually induce anxiety and nervousness. The key to rebalance this deficit of fluids is to drink eight glasses of fresh water a day. Water alone may not cure anxiety and other related disorders, but it can sure calm nerves and reduce headaches.

Simple healthy eating steps toward a better mood: For overall mental health remember the basics of good nutrition — plenty of fruits and vegetables, whole grains, lean meats and healthy oils. Eat a wide variety of foods to keep your diet interesting and to ensure you obtain all the micronutrients you need.