Some of the most thrilling discoveries about how the brain works, and how you can influence thought and behavior with food and supplements, come from new knowledge about the activity of neurotransmitter systems. It is these brain chemicals (so far about fifty have been identified) that substantially define who you are at every microsecond of your life. Flashing through neurons one by one, neurotransmitters lay down biochemical highways that carry your every thought and feeling through the brain's vast neuronal network. Without neurotransmitters, the lights in the brain would go out; they are the biochemical electrification system of your brain. They are the essence of your memory, intelllgence, creativity, and mood.
Until recently, the idea that food might profoundly and rapidly influence brain chemistry was considered scientifically ludicrous. Scientists thought the brain, of all organs, was particularly protected from the random permutations of nutrient invasions. It turns out the brain is uniquely responsive to food chemicals.
"The ability of a meal's composition to affect the production of brain chemicals distinguishes the brain from all other organs. The crucial compounds that regulate other organs are largely independent of whatever was in the last meal we ate -- but not the brain."
Richard Wurtman, research-psychiatrist, MIT
In the late 1970s, a team of researchers at the Massachusetts Institute of Technology, led by Dr. Richard Wurtman, had the first glimmering that food constituents could mimic drugs in regulating neurotransmitters causing changes in brain activity and behavior. Since then research into the nutritional origins and workings of neurotransmitters and their potential impact on personality and behavior has led to revolutionary findings.
The radical conclusion: The type of neurotransmitters your neurons make and release and their ultimate destiny within the brain depend greatly on what you eat. Obviously, that makes food a very big regulator of the brain.
The thinking goes this way: Your brain cells require certain nutrients as building blocks to make various neurotransmitters. Thus, the availability of a specific nutrient can dictate the levels and potency of a particular neurotransmitter. For example, brain cells need tryptophan, an amino acid 1n foods, to readily create serotonin, the good-mood messenger. Similarly, choline concentrated in egg yolk, ls required to make the neurotransmitter acetylcholine, critical for memory. The brain makes the neurotransmitter dopamine, essential for proper motor coordination, from an amino acid, tyrosine, found in high-protein containing foods. Other nutrients such as folic acid and fish oil can help determine the amount, character, and functioning of brain-altering neurotransmitters. When brain cells don't get enough of the right nutrients, neurotransmitter systems can go awry with disastrous consequences.
One way memory is destroyed, as in dementia and Alzheimer's is through a disruption of the neurotransmitter systems. Initially, researchers held neurons responsible for not synthesizing and releasing enough neurotransmitters. The solution: Devise ways to flood brain cells with more neurotransmitters, which is the rational behind many drug treatments for dementia and mood disorders. But scientists now know it's more complex than neurotransmitter shortage. New research focuses on the receiving apparatus of nerve cells -- how plentiful and "sensitive" dendritic receptors are at capturing and processing neurotransmitters. No matter how much of a neurotransmitter roams the brain, if receptors are not "activated" to pass the message on, it stops dead. Abnormalities in receptors can cause widespread trouble. In the brains of Alzheimer's patients, for example, the number of receptors for acetylcholine declines as does the receptors' ability to transmit messages. One new research dlrection: how to create more receptors and manipulate their sensitivity.
The important point is this: The composition of these neurotransmitters and the functional biochemistry of the receptors are changing all the time -- and some of that change is dependent on what you eat and what you do.