Review · Nutrition reviews · 2011Abstract only

Leucine as a nutrient to prevent and treat muscle loss and type 2 diabetes

What it found

In people, taking free leucine reversed the weakened muscle protein building response to protein in older adults.

Short-term studies suggest leucine supplements can help build muscle in older people, but no long-term studies exist.

What they found

Studies in people

Older adults, human studies

Recent studies in people show that taking free leucine can reverse the weakened muscle protein building response to amino acids or protein in older adults.

Muscle mass in elderly

Short-term studies suggest leucine supplements can stimulate muscle mass building in older people.

Animal and lab studies

Muscle protein building

In lab and animal studies, more amino acids led to more muscle protein building. This effect was strongest for leucine.

Insulin release

Leucine can act as a strong trigger for insulin release.

Other findings

Long-term evidence missing

There are no long-term nutrition studies to confirm the proposed benefits of leucine.

What the authors conclude

“Although short-term studies suggest that leucine supplementation can stimulate muscle mass accretion in the elderly, there are no long-term nutritional intervention studies to confirm this or the other proposed benefits of leucine as a pharmaconutrient.”
Leenders M, van Loon LJ, 2011

Also in their conclusions

  • They suggest that leucine represents an effective pharmaconutrient for the prevention and treatment of sarcopenia and type 2 diabetes.
  • They note that there are no long-term nutritional intervention studies to confirm this or the other proposed benefits of leucine as a pharmaconutrient.

How it was done

Amino acids act as building blocks for new protein and also as signals that control many cell processes. Leucine has been suggested as an effective nutrient to prevent and treat muscle loss and type 2 diabetes.

The paper reviews lab and animal evidence and recent human studies on leucine. It looks at how leucine affects muscle protein building and insulin release.

What it can’t tell you

  • We summarised it from the abstract only.
  • Short-term studies cannot show whether leucine helps build or keep muscle over months or years.
  • The human studies so far do not prove that leucine prevents or treats type 2 diabetes.

The paper

Title
Leucine as a pharmaconutrient to prevent and treat sarcopenia and type 2 diabetes
Type
ReviewThe authors read earlier studies and describe what they found. It isn’t a new study.
Evidence
Studies in people · animals · lab
Summarised from
Abstract only
Cite
Leenders M, van Loon LJ (2011). Leucine as a pharmaconutrient to prevent and treat sarcopenia and type 2 diabetes. Nutrition reviews. doi:10.1111/j.1753-4887.2011.00443.xPubMed 22029833DOI

Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error