Mental performance or relaxation can be controlled by choosing the right combination of foods. L-tyrosine and L-tryptophan are two amino acids which compete with one another to control brain functions. L-tyrosine is used by the brain to synthesize the neurotransmitters norepinephrine and dopamine, both of which are critical to clear, quick thinking; long-term memory; and feelings of alertness and stability. L-tryptophan is used by the brain to make the neurotransmitter serotonin, which is responsible for slowing down reaction time, imparting satiety after a meal and inducing sleep. L-tyrosine, found in protein-rich foods like meat, poultry, seafood, beans , tofu, and lentils, thus serves as a nutritional stimulant to the brain, whereas L-tryptophan, found in such foods as bananas, sunflowers seeds, and milk (and whose effects are augmented when consumed with carbohydrate-rich foods), slows mental functions.
If L-tyrosine reaches the brain before L-tryptophan, it will prime your brain to function at maximum performance levels all day (or all night, depending upon when you eat the meal or snack). But if L-tryptophan reaches the brain first, it will stimulate the production of serotonin, and your mental performance will ebb and your brain will begin to shut down, even in the middle of the day.
A program of mental fitness and control over your own levels of mental performance, memory, relaxation (and even depression) will facilitate the production of these amino acids and passage through the Blood Brain Barrier.
Glucose and Carbohydrates
Even though carbohydrates help relax the brain, they are necessary for maximum mental performance. If consumption is properly timed, carbohydrate-rich foods, such as pasta, bread, legumes, cereals, grains, fruits, and vegetables, can boost the brain's energy levels.
Carbohydrates (abundant in foods that are high in starch and sugar) are quickly broken down by the body into glucose. Carbohydrates enhance mental performance because the brain thrives on glucose. It supplies your brain with the most basic type of energy it needs to think, remember, solve problems, and control the rest of the body.
Foods that are rich in complex carbohydrates, such as whole grains, brown rice, unrefined cereals and flours, and vegetables and fruits, provide your brain with a steady supply of glucose.
Just as with protein, when you eat carbohydrates is critical to how your brain will respond. Timing is everything.
Breakfast: Begin the day with a mixture of protein and complex carbohydrates: low-fat milk with whole-grain cereal and fresh fruit.
Lunch: To renew mental energy for the afternoon, have a salad with low-fat dressing, shrimp cocktail, or chicken breast and fresh fruit for dessert.
Afternoon Snack: Use the midday snack to supply your brain with carbohydrates. Choose fresh fruit or low-fat crackers and six ounces of fruit juice or vegetable juice cocktail.
Dinner: Start the evening with complex carbohydrates-baked potato or corn-as a side dish; choose a choline-rich entree, such as lentil soup or fish; and finish with a low-fat frozen yogurt dessert.
Bedtime Snack: Relax your brain and prepare for a good night's sleep with warm low-fat milk, honey and banana.