betaalanine

Beta-alanine is a non-proteinogenic amino acid that occurs naturally in the body and is also consumed in the diet. It is chemically described as 3-aminopropanoic acid and is not used in protein synthesis like the standard amino acids.

Biosynthesis and dietary sources: In humans, beta-alanine is produced in the liver through the degradation of pyrimidines such as uracil and dihydrouracil. It is also obtained directly from dietary sources, primarily animal-based foods such as meat, poultry, and fish. Plant-based foods generally contribute less beta-alanine to the diet.

Role in the body: Beta-alanine is a precursor to the dipeptide carnosine, formed when beta-alanine combines with histidine in skeletal muscle. Carnosine acts as an intracellular pH buffer, helping to neutralize hydrogen ions that accumulate during high-intensity exercise. Because carnosine synthesis is limited by the availability of beta-alanine, increasing dietary or supplemental beta-alanine can raise intramuscular carnosine levels.

Supplementation and effects: Beta-alanine supplements are used to increase muscle carnosine content, which may improve performance in high-intensity activities lasting 1–4 minutes and delay fatigue. Typical dosing ranges from 2 to 5 grams per day, often divided into smaller doses to minimize tingling sensations (paresthesia). Some products employ sustained-release formulations.

Safety and regulation: Beta-alanine is generally considered safe at recommended doses, though high single doses can cause paresthesia. Long-term safety at high intakes is not well established. There is no widely recognized upper intake level, but individuals with kidney disease or other medical conditions should consult a healthcare professional before use. It is not a banned substance under major athletic governing bodies.