`I think I can, I think I can …': 5 brain chemicals and why they're important

Better Nutrition, March, 1999 by Ray Sahelian

5 brain chemicals and why they're important.

The `Brain Gang'

A summary of 5 brain chemicals and their major functions:

1. Acetylcholine is involved in memory and learning.

2. Dopamine is involved in sex drive, mood, alertness, and movement.

3. Norepinephrine is involved in alertness, arousal, and mood.

4. Serotonin is involved in mood, appetite control, emotional balance, and impulse control.

5. GABA is involved in relaxation and sedation.

Dozens of natural supplements have been introduced over the past few years that promise to enhance mental function. How do you determine which of these supplements is appropriate for you? And how do you decide how much to take, in what combinations, how often, and for how long? The whole process is admittedly complicated. Even healthcare practitioners experienced in nutritional therapy can't make complete sense of it all. Therefore, it's important for us to look at specifically how vitamins, herbs, nutrients, and hormones can influence the function and health of the brain and mind.

From time to time, this column will look at individual supplements and provide practical guidelines for their use. In this very first "Brain Boosters" column, though, I thought it would be appropriate to give a brief explanation of brain chemicals -- also known as neurotransmitters -- that influence thinking, mood, alertness, sex drive, and memory. Supplements that have an influence on the mind do so mostly through their effect on neurotransmitters. At least 100 neurotransmitters are present in the brain; here are five which play a particularly significant role.

1. Acetylcholine

Acetylcholine is mostly involved in learning and memory. Nutrients that influence brain acetylcholine levels include choline, DMAE (dimethylaminoethanol), lecithin, and CDP-choline. In Alzheimer's disease, there is a shortage of acetylcholine, and one of the ways doctors have tried to increase the levels of this neurotransmitter is by prescribing drugs, such as tacrine, that inhibit an enzyme that breaks down acetylcholine. A newly available extract from Chinese club moss, huperzine A, may work in a similar manner to tacrine.

2. Dopamine

A number of psychiatric disorders, particularly schizophrenia, Parkinson's disease, and mood disorders, are attributed to imbalances in dopamine levels. Elevation of dopamine levels often leads to an improvement in mood, alertness, and sex drive. Several nutrients are thought to elevate dopamine levels, including the amino acid tyrosine, and certain B vitamins, such as NADH (the activated form of vitamin B-3, or niacin).

3. Norepinephrine

The amino acids phenylalanine and tyrosine are converted into dopamine, which, in turn, is converted into norepinephrine. Increases in brain levels of norepinephrine lead to arousal and mood elevation, but excessive amounts can cause irritability, anxiety, and insomnia.

4. Serotonin

Serotonin helps regulate a wide range of psychological and biological functions including mood, anxiety, arousal, and aggression. The prescription drug Prozac, a common antidepressant, elevates serotonin levels. There is an over-the-counter nutrient called 5-hydroxytryptophan (5-HTP) that is the immediate precursor to serotonin, which can also elevate brain serotonin levels.

The starting point in making serotonin is tryptophan, one of the amino acids we ingest through food, particularly meat, fish, and other protein foods. If enough tryptophan is not supplied to the brain, serotonin levels drop. Tryptophan is converted into 5-HTP, which is then converted into serotonin. After serotonin is made, the pineal gland is able to convert it at night into the sleep hormone melatonin.

5. GABA

Gamma-aminobutyric acid (GABA) is the most important and widespread inhibitory neurotransmitter in the brain. Excitation in the brain must be balanced with inhibition. Too much excitation can lead to restlessness, irritability, insomnia, and even seizures. GABA is able to induce relaxation, analgesia, and sleep. Barbiturates and benzodiazepines are prescriptions known to stimulate GABA receptors, and bring on relaxation.

Summary

Through the proper use of nutrients, healthcare practitioners are able to manipulate levels of brain chemicals in order to fight depression, improve memory, or enhance a number of mental functions.

The anatomy of memory

Memory is as natural to us as breathing. It is an ability we all have, yet rarely ever think of -- unless we perceive that we are losing that ability. Memory lapses are an annoyance in themselves, but worse is the anxiety that often comes along with them. Probably the greatest fear provoked by lapses in memory is that of Alzheimer's disease, a progressive and debilitating disease that usually starts in midlife with minor defects in memory and behavior. Although this is a fairly common disorder among older people, it is important to realize that most memory lapses have nothing to do with Alzheimer's disease.

People have come to expect that, as they age, their ability to remember will begin to deteriorate; that their powers of recall will diminish. This is not necessarily true. The aging process itself has little, if any, bearing on the ability to recall information. Occasional memory lapses are a natural, normal part of life at virtually any age, but with proper diet and nutrition, the memory should remain sharp and active well into one's 90s or beyond.