Please note that this section reports on claims that have not yet been substantiated
Leucine may improve healing of skin and bones. It may increase muscle development
and lean body mass. It may also increase production of human growth hormone (HGH).
It may even help control blood sugar.
Amino acids (AAs) are available as individual AAs or in AA combinations. They also
come as part of multi-vitamins, proteins, and food supplements. The forms include
tablets, fluids, and powders.
Note that by eating enough protein in your diet, you get all of the amino acids you
You should take leucine supplements with valine and isoleucine.
There are no conditions that increase how much leucine you need.
Side effects, toxicity, and interactions
Using a single amino acid supplement may lead to negative nitrogen balance. This can
decrease how efficient your metabolism is. It can also make your kidneys work harder.
In children, taking single amino acid supplements may also cause growth problems.
You should not take high doses of individual amino acids for long periods of time.
Very high doses of leucine may cause low blood sugar (hypoglycemia). It may also cause
pellagra. Symptoms of this condition can include skin lesions, hair loss, and gastrointestinal
Women who are pregnant or breastfeeding shouldn’t use leucine supplements. People
who have maple syrup urine disease (MSUD), a rare inherited issue, shouldn’t take
either. They also shouldn’t take the other branched-chain amino acids. These include
isoleucine and valine.