Updated June 3, 2013
Familiar examples of the dramatic behavioral changes resulting from our drinking habits are the effects of alcohol and caffeine. Alcohol is a depressant, even though the first evidences of intoxication may be an elevation in mood. Caffeine for most people is a mood elevator, but this can soon lead to an uncomfortable anxiety.
Withdrawal from caffeine can be a problem, characterized by headaches and depression for those who are trying to quit. Although the uncomfortable symptoms last for only a few days, their victims consider themselves to be severely tested (and, alas, not always heroically triumphant).
However, many other substances can affect our tendency to be anxious or depressed, including some of the very foods we eat. Probably the best studied example of a specific “behavior modifying” substance in our foods is the essential amino acid tryptophan. This amino acid is converted in the brain into serotonin, a powerful agent in a variety of responses made by the brain. Serotonin regulates over-reactiveness to different stimuli from smell, taste, vision, and social relationships. Accordingly, sleep patterns, sexual behavior, aggressiveness, physical activity, perceptions (including pain), and moods are affected. Tryptophan pills have been used to reverse insomnia, prevent muscle spasms, and in some cases to relieve depression.
The amount of tryptophan in the foods that are eaten has only a small influence upon the amount of tryptophan that enters the brain. The most important factor determining the total amount of tryptophan that does enter the brain is the concentration of other large-molecule amino acids concurrently present in the blood. Large-molecule amino acids, among them tryptophan, compete with each other to enter “gates” between the circulating blood stream and the relatively confined brain fluids. A high-protein meal (full of meats, dairy foods, and eggs) provides many other amino acids that compete with tryptophan for entry into the brain; the end result is less tryptophan passing into the brain and a decrease in the synthesis of serotonin. Conversely, a low-protein, carbohydrate-rich diet (full of starches, vegetables, and fruits) results in the highest levels of serotonin in the brain, because fewer large-molecule amino acids are competing with tryptophan to enter the brain. For you this means less hyperactivity, anxiety, depression, and insomnia-provided you eat that healthier diet.
In some people anxiety, depression, and fatigue are caused by allergic reactions to foods. The most common causes of food allergies are dairy products, followed by eggs. Other common culprits are wheat, corn, and citrus fruits, but almost any foodstuff eaten by human beings finds somewhere an individual who is allergic to it. These reactions are often subtle and difficult to recognize until the offending food has been eliminated, either by accident or by intention, and then, later, when the body is challenged with the suspect food, a recognizably adverse reaction occurs.
A serious psychological disease caused by foods in some people is schizophrenia. In hospital-based studies, some patients have been identified who react with dramatic behavioral changes to milk products and high-gluten foods (like wheat, barley, and rye). Some people with schizophrenia have actually been cured of their disease by changing their diet, to eliminate the trouble-making foodstuff.
When I see a patient who says he is depressed, I usually begin my course of treatment by paying close attention to some general principles of medicine and health. First, of course, I examine him for the presence of any serious organic disease and always check for adequacy of thyroid function. I consider the amounts of coffee, and alcohol that he drinks, and the foods he chooses to eat. I also check to see if any medications may be causing changes in his behavior. High blood pressure medications (Beta-blockers), birth control pills, tranquilizers, and, indeed, almost any other medication should be suspected.
If all organ systems seem to be well medically, then I suggest that the patient change to a starch-based diet, and I remind him that daily exercise, with something as simple as walking, helps to relieve minor depression and anxiety.
Stop taking any drugs (under a doctor’s supervision) that might be causing anxiety or depression. Stop drinking alcohol (this too may need to be done under a doctor’s supervision) and caffeinated beverages. Change to a starch-based diet. Exercise daily. Look for a professional person (minister, counselor, psychologist, psychiatrist) who is a good listener, with whom to talk over your problems. Only as a last resort consider taking doctor prescribed psycho-active drugs.
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