What it does in the body
- Muscle protein synthesis (BCAA)
- Glycogenic amino acid (glucose production during fasting)
- Nitrogen balance maintenance
- Central nervous system function and mental vigor
- Tissue repair and wound healing
How much you need (Daily Value)
| Group | Recommended | Source |
|---|---|---|
| Adult male | 26mg/kg/day (~1.8g for 70kg) | WHO/FAO/UNU |
| Adult female | 26mg/kg/day (~1.6g for 60kg) | WHO/FAO/UNU |
| Pregnancy | 32mg/kg/day | WHO |
| Children | 28-44mg/kg/day depending on age | WHO |
| Older adults | 26mg/kg/day | WHO |
Richest food sources
| Food | Amount | Where |
|---|---|---|
| Chicken breast (cooked) | 1.3g per 100g | global |
| Beef (lean, cooked) | 1.2g per 100g | global |
| Tuna (cooked) | 1.1g per 100g | global |
| Cottage cheese | 0.8g per 100g | europe |
| Soybeans (cooked) | 0.7g per 100g | east-asia |
| Lentils (cooked) | 0.4g per 100g | south-asia |
| Peanuts | 1.1g per 100g | global |
| Seaweed (nori, dried) | 2.5g per 100g | east-asia |
If you don't get enough
Mild: Fatigue, reduced exercise tolerance, mild insomnia
Moderate: Muscle wasting, impaired coordination, neurological irritability, skin hypersensitivity
Severe: Severe neurological dysfunction, profound muscle catabolism, growth failure in children
Time to onset: Exercise intolerance within 1-2 weeks; clinical deficiency symptoms within 4-6 weeks
Too much
Upper limit: No established UL; doses up to 20g/day in BCAA mixtures used in studies
Nausea, tingling, hallucinations at very high isolated doses. May impair serotonin synthesis by competing for brain transport
How well you absorb it
90-95% from animal proteins; 80-90% from plant sources
Helped by: Vitamin B6 (BCAA transamination cofactor), Balanced BCAA ratio (2:1:1 leucine:isoleucine:valine), Adequate caloric intake
Hindered by: Excess leucine (competitive depletion), Alcohol, Liver disease (impaired BCAA metabolism)
Cooking & storage
Heat-stable; normal cooking and food processing preserve valine content well.
Nutrisize Health totals every nutrient from what you actually eat, against targets set for your age and sex, and flags what's short — across 4,995 foods, on your device.
