November/December 2006

Brain Food: The Real Dish on Nutrition and Brain Function

by Jeanne Erickson

According to Dr. Boyd Eaton of Emory University in Atlanta, dietary patterns that have shaped our brains throughout human history have gone through some changes. A Stone Age diet consisted of 65 percent fruits, vegetables, nuts, legumes and honey and 35 percent lean game, wild fowl, eggs, fish and shellfish. Today's diet looks quite different, with the addition of "new foods" consisting of cereal, grains, sugar, sweeteners, dairy products, separated fats and alcohol. Twenty-eight percent of the modern diet consists of fatty meat, poultry, eggs, fish and shellfish; 17 percent is fruits, vegetables, legumes and nuts.

So what are "Brain Foods"?

The three key substances required to keep your brain healthy and your mental processes operating effectively are nutritious food, water and oxygen. Many components of food are crucial to brain development and function, including proteins, carbohydrates, fats, and vitamins and minerals.

Protein
Protein is found in, among other foods, meat, fish, milk and cheese. Protein provides the building blocks for most of the body's tissues, nerves and internal organs. Proteins are used to make neurotransmitters, the "messengers" that carry information from brain cell to brain cell. Neurotransmitters are made from amino acids, which proteins are made of. Vitamins and minerals are needed to convert amino acids into powerful neurotransmitters.

Deficiencies in protein can also result in Protein Energy Malnutrition, which leads to poor school performance by children, and can affect social/emotional development in the very early years as it leaves the child withdrawn, lethargic and passive.

Carbohydrates
Grains, fruits and vegetables are key sources of carbohydrates. Digestion causes the breakdown of carbohydrates into glucose (sugar), which is the brain's primary source of energy. If your glucose levels fluctuate too much, you may experience mental confusion, dizziness and, if severe, convulsions and loss of consciousness.

Carbohydrates enhance the absorption of tryptophan, which is converted into serotonin in the brain. Serotonin is a brain chemical that has a powerful effect on one's mood. Within about thirty minutes of eating a carbohydrate-heavy meal, you will feel more calm and relaxed. The effect will last several hours.

Fats
The brain is more than 60 percent fat. This is because brain cells are covered by a myelin sheath that is composed of approximately 75 percent fat. Fats also play a crucial role as messengers. They regulate key aspects of the immune system, blood circulation, inflammation, memory and mood. Omega-3 fatty acids are essential to the optimum performance of your brain. Lack of omega-3 fats in your diet can lead to depression, poor memory, low IQ, learning disabilities, dyslexia, ADD and many other mental disorders. To ensure that your diet is rich in omega-3 fats, you should eat plenty of oily fish like salmon, sardines, trout, tuna, herring, mackerel and anchovies. Nuts are another good source of omega-3 fats. Walnuts even look a little like brains!

Vitamins and Minerals
Vitamins and minerals are essential for the growth and functioning of the brain. The B complex vitamins are particularly important for the brain, and play a vital role in producing energy. Vitamins A, C and E are powerful antioxidants and promote and preserve memory in the elderly. Minerals are also critical to mental functioning and performance. Magnesium and manganese are needed for brain energy. Sodium, potassium and calcium are important in the thinking process, and facilitate the transmission of messages.

Neurotransmitters and Nutrition

As noted above, proper nutrition is key to production of neurotransmitters. Protein plus vitamins and minerals help build strong connections. The three key neurotransmitters are acetylcholine, dopamine and serotonin.

Acetylcholine (ACh) is involved in voluntary muscle movement, behavioral inhibition and memory. Acetylcholine rich foods include egg yolks, peanuts, wheat germ, liver, meat, fish, milk, cheese and vegetables (especially broccoli, cabbage and cauliflower).

Dopamine is important in movement, attention and learning. It is involved with voluntary movement, and emotional arousal. Dopamine rich foods include all proteins, such as meat, milk products, fish, beans, nuts and soy products. Three to four ounces of protein will help you to feel energized, more alert and more assertive.

Serotonin is involved with arousal and sleep, mood, appetite and sensitivity. However, it is also part of the brain's reward system, producing feelings of pleasure. Serotonin rich foods are carbohydrate-based, including pasta, starchy vegetables, potatoes, cereals and breads.

Eating for a Healthy Brain

Here are six simple tips for a brain-friendly diet:

There is a lot of truth to the old adage, "You are what you eat." As our understanding and appreciation of the complex interplay between nutrition and brain function continue to increase, so does the importance of taking those words to heart.

Sources:

Carper, Jean, Your Miracle Brain, Harper Collins, 2000.

Zigler, Edward, The First Three Years and Beyond: Brain Development and Social Policy, Yale University Press, 2003.