Amino Acids
Amino acids are the building blocks of protein and many neurotransmitters. The supplements below are commonly used for athletic performance, sleep, mood, and recovery, each graded by the quality of the supporting research.
14 amino acids supplements in the library.
5-HTP
A direct serotonin precursor for mood and sleep, use with care.
Collagen
The structural protein for skin, joints, and connective tissue.
Creatine
The most-studied performance and cognition supplement.
Glucosamine
An amino sugar that supports cartilage and joint comfort.
Glycine
A calming amino acid for sleep, collagen, and metabolic health.
L-Arginine
The nitric oxide precursor for blood flow and cardiovascular health.
L-Citrulline
A superior nitric oxide booster that outperforms arginine for pumps and endurance.
L-Glutamine
The gut-lining repair amino acid and immune fuel.
L-Theanine
Calm, focused alertness from green tea.
L-Tryptophan
The dietary precursor to serotonin and melatonin.
L-Tyrosine
The dopamine precursor that sharpens focus under stress.
NAC
A powerful antioxidant precursor and lung-health support compound.
Taurine
A conditionally essential amino acid for the heart, muscles, and calm focus.
TMG (Trimethylglycine)
A methyl-donor cousin of glycine for homocysteine, liver, and power.
Where to buy amino acids
The most-researched options in this category. Choose third-party-tested brands in the forms each supplement's page recommends.
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