Isoleucine
A branched-chain amino acid for muscle and energy.
What is Isoleucine?
Isoleucine is an essential branched-chain amino acid (BCAA), grouped with leucine and valine. BCAAs are metabolized mainly in muscle rather than the liver, where isoleucine helps regulate energy use, blood-sugar uptake and the repair of muscle tissue after exertion.
Health benefits of Isoleucine
- Helps muscles take up glucose for energy during exercise
- Supports muscle repair and recovery
- Contributes to hemoglobin formation
- Plays a role in immune function and wound healing
Top food sources of Isoleucine
See full rankingMeat, fish, poultry, eggs, cheese, soy, lentils and seeds. Values shown per 100 g.
Egg, white, dried, powder, glucose reduced
5,023 mg
Egg, white, dried, flakes, glucose reduced
4,689 mg
Egg, white, dried
4,581 mg
Soy protein isolate, PROTEIN TECHNOLOGIES INTERNATIONAL, SUPRO
4,300 mg
Soy protein isolate
4,253 mg
Soy protein isolate, potassium type
4,253 mg
Soy protein isolate, potassium type, crude protein basis
4,253 mg
Soy protein isolate, PROTEIN TECHNOLOGIES INTERNATIONAL, ProPlus
4,200 mg
Seaweed, spirulina, dried
3,209 mg
Seal, bearded (Oogruk), meat, dried (Alaska Native)
3,134 mg
Egg, whole, dried, stabilized, glucose reduced
3,014 mg
Soy protein concentrate, produced by alcohol extraction
2,942 mg
How much Isoleucine do you need?
There is no FDA Daily Value for individual amino acids. The WHO estimate is about 20 mg per kg of body weight per day, easily met by everyday protein foods.
Isoleucine deficiency
Deficiency is uncommon with adequate protein; shortfalls can contribute to fatigue, muscle wasting and weakness.
Nutrition data per 100 g from the USDA & FooDB databases. Daily Values follow the FDA 2016+ labeling standard for a 2,000-calorie diet. This guide is for general information and is not medical advice.
Frequently asked questions
What does Isoleucine do?
Isoleucine is an essential branched-chain amino acid (BCAA), grouped with leucine and valine. BCAAs are metabolized mainly in muscle rather than the liver, where isoleucine helps regulate energy use, blood-sugar uptake and the repair of muscle tissue after exertion.
How much Isoleucine do I need per day?
There is no FDA Daily Value for individual amino acids. The WHO estimate is about 20 mg per kg of body weight per day, easily met by everyday protein foods.
Which foods are highest in Isoleucine?
Per 100 g, some of the richest sources are Egg, white, dried, powder, glucose reduced, Egg, white, dried, flakes, glucose reduced, Egg, white, dried, Soy protein isolate, PROTEIN TECHNOLOGIES INTERNATIONAL, SUPRO, Soy protein isolate.
What happens if I don't get enough Isoleucine?
Deficiency is uncommon with adequate protein; shortfalls can contribute to fatigue, muscle wasting and weakness.