2-Acetylamino-3-(4-Hydroxyphenyl)-Propanoic Acid, Acetyl-L-Tyrosine, Acétyl-L-Tyrosine, L-Tyrosine, N-Acetyl L-Tyrosine, N-Acetyl-L-Tyrosine, N-Acétyl L-Tyrosine, N-Acetyl-Tyrosine, N-Acétyl-Tyrosine, Tirosina, Tyr, Tyrosinum, 2-amino-3-(4-hydroxyphenyl)propionic acid.
Overview InformationTyrosine is an amino acid. Amino acids are the building blocks of protein. The body makes tyrosine from another amino acid called phenylalanine. Tyrosine can also be found in dairy products, meats, fish, eggs, nuts, beans, oats, and wheat.
Tyrosine is most commonly used in protein supplements to treat an inherited disorder called phenylketonuria (PKU). People who have this disorder can't process phenylalanine properly. As a result they can't make tyrosine. To meet their bodies' needs, supplemental tyrosine is given.
Tyrosine is also commonly used to improve learning, memory, and alertness, especially during stressful situations.
How does it work?The body uses tyrosine to make chemical messengers that are involved in conditions involving the brain such as mental alertness.
Uses & Effectiveness
- Phenylketonuria (PKU). People with PKU are not able to process the amino acid phenylalanine. This amino acid is used by the body to make tyrosine. Because of this, people with PKU can have low levels of tyrosine in the body. To prevent tyrosine levels from becoming too low, people with PKU are advised to consume medical foods containing tyrosine but very little phenylalanine. Tyrosine levels in the blood are regularly measured by physicians.
Possibly Effective for
- Mental performance. Research shows that taking tyrosine improves mental performance under stressful conditions These include cold-induced stress or noise-induced stress.
- Memory. Research shows that taking tyrosine improves memory during stressful conditions. These include cold-induced stress or multi-tasking. Tyrosine does not seem to improve memory during less stressful situations.
- Improving alertness following the loss of sleep. Taking tyrosine helps people who have lost a night's sleep stay alert for about 3 hours longer than they otherwise would. Also, early research shows that tyrosine improves memory and reasoning in people who are sleep-deprived.
Possibly Ineffective for
- Attention deficit disorder (ADD). Taking tyrosine by mouth does not improve symptoms in children or adults with ADHD.
- Depression. Taking tyrosine by mouth does not improve symptoms of depression.
- Exercise performance. Taking tyrosine before running or cycling does not improve strength, stamina, or performance.
Insufficient Evidence for
- Alcoholism. Early research shows that taking tyrosine along with other amino acids and a multivitamin reduces withdrawal symptoms and stress in alcoholics. It is not clear if this effect is due to tyrosine, other ingredients, or the combination.
- Cocaine dependence. Early research shows that taking tyrosine in the morning and L-tryptophan at night does not reduce cravings or withdrawal symptoms in people with cocaine dependence.
- Dementia. Early research shows that taking tyrosine, 5-hydroxytryptophan, and carbidopa by mouth does not improve symptoms in people with dementia.
- High blood pressure (hypertension). Early research shows that taking tyrosine by mouth does not reduce blood pressure in people with slightly high blood pressure.
- Excessive sleepiness (narcolepsy). Research shows that taking tyrosine by mouth reduces some symptoms of narcolepsy, such as feelings of tiredness, based on patient ratings. But it does not seem to improve most symptoms based on clinical assessment.
- Schizophrenia. Early research shows that taking tyrosine along with the drug molindone does not improve symptoms of schizophrenia better than molindone alone.
- Weight loss. Taking a combination of tyrosine, cayenne, green tea, caffeine, and calcium slightly reduces body fat by about 0.9 kg in overweight people. But the supplement does not improve blood pressure, heart rate, or the excretion of fat in the feces.
- Symptoms of heroin withdrawal. Early research shows that taking a combination of tyrosine, 5-hydroxytryptophan (HTP), phosphatidylcholine, and L-glutamine, improves mood and the ability to sleep in men addicted to heroin. It also seems to reduce withdrawal symptoms.
- Wrinkled skin. Applying a preparation containing 10% vitamin C, acetyl tyrosine, zinc sulfate, sodium hyaluronate, and bioflavonoids seems to improve wrinkling, skin yellowing, roughness, and skin tone in people with sun-damaged skin.
- Alzheimer's disease.
- Chronic fatigue syndrome (CFS).
- Erectile dysfunction (ED).
- Heart disease.
- Parkinson's disease.
- Premenstrual syndrome (PMS).
- Other conditions.
Side Effects & SafetyTyrosine is LIKELY SAFE when taken by mouth in food amounts. It is POSSIBLY SAFE when taken by adults as a medicine, short-term, or when applied to the skin. Tyrosine seems to be safe when taken by mouth in doses up to 150 mg/kg per day for up to 3 months. Some people experience side effects such as nausea, headache, fatigue, and heartburn.
There isn't enough information available to know if tyrosine is safe for children to use in medicinal amounts. Don't give it to children without the advice of your healthcare provider until more is known.
Special Precautions & Warnings:Pregnancy and breast-feeding: There isn't enough information available to know if tyrosine is safe to use during pregnancy and breast-feeding. Stay on the safe side and only use in food amounts.
Overactive thyroid (hyperthyroidism) or Graves' disease: The body uses tyrosine to make thyroxine, a thyroid hormone. Taking extra tyrosine might increase thyroxine levels too much, making hyperthyroidism and Graves disease worse. If you have one of these conditions, don't take tyrosine supplements.
Be cautious with this combination
Levodopa interacts with TYROSINE
Tyrosine might decrease how much levodopa the body absorbs. By decreasing how much levodopa the body absorbs, tyrosine might decrease the effectiveness of levodopa. Do not take tyrosine and levodopa at the same time.
Thyroid hormone interacts with TYROSINE
The body naturally produces thyroid hormones. Tyrosine might increase how much thyroid hormone the body produces. Taking tyrosine with thyroid hormone pills might cause there to be too much thyroid hormone. This could increase the effects and side effects of thyroid hormones.
The following doses have been studied in scientific research:
- For mental performance: A single dose of 100-300 mg/kg of tyrosine has been taken before a stressful mental task.
- For memory: 150-300 mg/kg of tyrosine has been used before a memory task.
- For improving alertness following the loss of sleep: 150 mg/kg of tyrosine in a split dose has been used.
- For PKU: Foods and medical foods providing 4-6 grams of tyrosine daily are recommended. Women with PKU who are pregnant or breastfeeding are advised to consume foods providing 6-7.6 grams of tyrosine daily. A doctor will measure tyrosine levels in the blood to make sure they don't become too high or too low. For most people with PKU, additional separate supplementation with free tyrosine is not recommended. It can cause wide variations in the amount of tyrosine in the blood. This could cause unwanted side effects.
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