Tyrosine may be the natural antidote to today's fast-paced lifestyle. Of all the supplements I study and prescribe in my practice, tyrosine is one of my absolute favorites. With its help, I've seen people emerge from the fog of depression, handle stress better, and generally improve their condition.
Tyrosine is an amino acid - a building block for protein - that is found in every day dairy products such as cheese and milk, and meats such as chicken and turkey. While all of the 20-odd amino acids that form our bodily proteins serve as building blocks for the brain, tyrosine plays an especially important role in keeping the nervous system alive and running. Just like two other amino acids, tryptophan [found in milk] and phenylalanine [found in the sugar substitute, aspartame], tyrosine is known as an “aromatic” amino acid and has a special ring structure shaped like a hexagon. Unlike non-aromatic amino acids, any dietary tyrosine we consume is readily absorbed into our brains. This quality allows tyrosine the heady power to tinker with our moods, feelings, emotions, and cognitive abilities.
Tyrosine is the precursor of three of the most crucial neurotransmitters used as chemical messengers by the neuronal cells that wire our brains: dopamine, norepinephrine, and epinephrine [also known as adrenaline]. The life-changing power of anti-depressant drugs is often due to their ability to increase both dopamine and norepinephrine. Though the role of norepinephrine is subtle, it is absolutely necessary for preparing our bodies for the fight-or-flight reaction. It conserves energy and stimulates adrenaline release. A study in Military Medical Journal shows that intensely stressful situations, like fighting in a war, can use up our stores of norepinephrine. Tyrosine not only restores low levels of norepinephrine, but also improves performance and cognitive functioning during times of extreme pressure.
Studies of human subjects at high altitudes and freezing temperatures show that tyrosine supplements prevent the learning, motor, and memory difficulties that usually arise in stressful environments. Second, tyrosine is a source of energy. A study on lab animals showed that tyrosine renewed both enthusiasm and motivation normally eliminated by stressful surroundings. Similar research has shown that tyrosine can restore significant amounts of energy to sufferers of chronic fatigue syndrome and dysthymia - depression that is not as severe as full-blown clinical depression - by acting as a natural stimulant.
This brain-boosting nutrient can also be useful as an analgesic and as a potential treatment for disorders like narcolepsy. Narcolepsy is a chronic neurological disorder caused by the brain’s inability to regulate sleep-wake cycles, normally. Tyrosine may even help ameliorate post-menopausal distress.
Tyrosine and the Human Brain
How can a single amino acid, like tyrosine, affect memory, mood, concentration, and energy? It all begins in the brain. Our bodies are wired with a complex network of hundreds of billions of interconnecting cells called neurons, which take information from the outside world and relay it to our central command center, the brain. The brain is responsible for integrating and making sense of all the sounds, sights, smells, and data rushing in from the world and translating them into the movements we make and the emotions we feel.
Neurons, like living computer chips, send messages through our nervous system in two forms: electrical impulses, which shoot signals down the length of a neuron, and chemical messengers, which carry these signals between cells. These chemical messengers are known as neurotransmitters, and the trillions of notes they send through the brain every second make them amazingly fast purveyors of information.
Our brain's instantaneous co-ordination of the over 50 known or suspected neurotransmitters is crucial. Each neurotransmitter has its own unique character and can pass news on only to neurons that have receptors fitting its chemical shape. Some excite the brain while others calm it and diminish the impact of their chemical counterparts.
A lot of what we know about the importance of these chemicals, unfortunately, comes from what happens to people who are lacking these important messengers. Dopamine, for example, helps regulate movement and is also a profound pleasure chemical that helps us fall in love, savour a chocolate fudge sundae, or set and achieve goals. But, it can also trigger addictive behavior. The degeneration of dopamine-using neurons in the brain can lead to Parkinson’s disease - a terrifying illness that inhibits our conscious ability to initiate, sustain, or terminate movement. Too little dopamine in certain centers of the brain may lead to attention deficit hyperactivity disorder [ADHD], or depression.
For people who are stressed, norepinephrine is a crucial neurotransmitter. When you are walking alone down a dark alley and hear footsteps close behind you, your heart begins to pound, you breathe rapidly and shallowly, and you feel suddenly alert. Your body has just released a flood of stress hormones, including norepinephrine. This response to stress shuts off normal processes like digestion and immune response in order to save energy for fighting off - or, fleeing - the alley prowler. Unfortunately, constant stress can use up necessary norepinephrine levels. This is where tyrosine, as a building block for norepinephrine, is so valuable.
Tyrosine can be a great energy booster and stress reliever. It works best, however, when norepinephrine levels are low in the body. If you are thinking about supplementing with tyrosine to give you energy, discuss first with your doctor.