Carnosine
Carnosine is a dipeptide of beta-alanine and L-histidine that occurs naturally in skeletal muscle and brain tissue. The level in muscle is mainly controlled by the availability of beta-alanine, which is why beta-alanine and not carnosine is the common supplement in sports.
What is carnosine
Carnosine is a dipeptide — two amino acids linked together — consisting of beta-alanine and L-histidine. It was discovered in muscle tissue in the early 1900s by the Russian chemist Vladimir Gulevitj. The concentration is highest in fast-twitch muscle fibres and in certain parts of the brain, and is generally higher in individuals with a lot of muscle mass.
Why beta-alanine is more often sold than carnosine
This is the most practically relevant point. Carnosine taken orally is largely broken down by the enzyme carnosinase in the blood and intestinal mucosa into its two components. The muscle then rebuilds carnosine, and the limiting factor in this process is beta-alanine — histidine is usually in excess.
Carnosine as a supplement is therefore often justified by other reasoning than muscle content.
Zinc carnosine is something different
Zinc-L-carnosine, known in Japan as polaprezinc, is a chelate between zinc and carnosine and is treated in the literature as a separate substance with its own uses. It is therefore not interchangeable with carnosine in a comparison.
Research status
Carnosine has been studied for its chemical properties, including its ability to bind reactive carbonyl groups. There is preclinical literature in several areas and a smaller number of human studies. There is no EU-approved health claim for carnosine.
