The amino acid phenylalanine converts into another amino acid, tyrosine. Tyrosine is essential for making the brain neurotransmitters norepinephrine, epinephrine and dopamine. Tyrosine uses the protein from the food you eat to produce neurotransmitters that affect your mood, focus, memory and alertness. Your brain relies on tyrosine for brain function and producing thyroid hormones. Low levels of tyrosine can cause mental retardation due to an underactive thyroid.
Norepinephrine
The neurotransmitter norepinephrine allows you to concentrate, become motivated and be alert. It travels through your blood, stimulating your brain. You need norepinephrine to make new memories and store them for referencing later. If your body does not produce enough norepinephrine, you will become confused, lethargic, depressed and develop memory loss.
Epinephrine
Tyrosine converts the neurotransmitter epinephrine into an amino acid that is released from your adrenal gland. Epinephrine, more commonly known as adrenalin, increases your heart rate and breathing. This produces oxygen-rich blood that travels to your brain and muscles, increasing your energy, sharpening your senses, improving your memory and decreasing pain sensitivity. Tyrosine produces epinephrine in times of stress or danger so you are better able to cope with the situation.
Dopamine
Dopamine helps you stay motivated and assertive throughout your day. It allows you to handle daily stress and problems. Lack of sleep and too much stress lowers your dopamine level, making your brain less active. Taking in too much caffeine, alcohol and sugar also depletes dopamine. Lowered dopamine in the brain causes attention deficit disorder and cognitive problems. The elderly suffer from weakened brain activity because dopamine receptors decline with age.
Schizophrenia is a disease caused by the parts of the brain that deal with ideas, attention and emotion, and life skills do not function properly. The brain of a schizophrenic has excessive dopamine activity resulting in delusions and paranoia.
Food Sources
Eating foods rich in tyrosine will help you stay motivated and alert. Almonds, soy, bananas, milk, yogurt, cheese, eggs, lima beans, avocados, pumpkin and sesame seed, aspartame, fish, chicken and turkey are good sources of tyrosine.
