Benefits of Amino Acid

1. Muscle maker.

By middle age, you rapidly lose muscle mass, even if you exercise. You can counter some of this loss by taking branched-chain amino acids (BCAAs)—leucine, isoleucine and valine. Of these, leucine is by far the most important for making new muscle, and a recent analysis of nine studies confirmed its muscle-enhancing effect. Leucine works for seniors, too, who might actually benefit the most. Adding vitamin D and exercising amplifies the benefits.

Dose: Take a daily BCAA supplement containing approximately 2.5 grams of leucine, 1.25 grams of isoleucine and 1.25 grams of valine. Alternatively, take 3–4 grams of leucine daily.

2. Mood lifter.

Amino acid L-tryptophan and 5-hydroxytryptophan (5-HTP) form the key building block of serotonin, the neurotransmitter that protects against anxiety and depression. Supplements have been found helpful for these disorders, as well as with insomnia.

Dose: Take either 500 mg of L-tryptophan or 50 mg of 5-HTP three times daily.

3. Stress buster.

The amino acid gamma- aminobutyric acid, or GABA, functions as a neurotransmitter that promotes a relaxed feeling while also increasing mental focus. It works by helping the brain tune out distracting “background noise.” A 2015 study by Dutch researchers found GABA supplements improve decision making and reaction times. Theanine, an amino acid found in high-quality green tea, boosts the brain’s alpha waves, which can reduce anxiety. GABA and theanine may be taken together.

Dose: Try 200–500 mg daily of GABA. You can add 200 mg daily of theanine.

4. Immune strengthener.

The preferred form of the amino acid cysteine, N-acetylcysteine (NAC) is an essential building block of glutathione, the body’s principal antioxidant. An Italian study found that NAC supplements greatly reduced flu symptoms among seniors. Its side benefits include supporting the liver’s detox efforts and lung function.

Dose: Take 600 mg daily. Double the amount during the cold and flu season.

5. Blood-vessel toner.

L-arginine functions as the precursor to nitric oxide, a compound that regulates blood-vessel flexibility. Increased flexibility is good for the cardiovascular system, and some research indicates that this amino acid can lower blood pressure. Men also need healthy blood-vessel tone for erections, and arginine may help men with erectile dysfunction, as well. Some research has also found that a combination of arginine and the herb yohimbe might increase blood flow to the vagina, which can increase arousal and help women achieve orgasm.

Dose: Try 1,000 mg of arginine three times daily.