Protein basics
Before any single amino acid, there's total protein. Get this right first.
How much protein?
The U.S. Recommended Dietary Allowance is 0.8 grams per kilogram of body weight per day, the amount needed to prevent deficiency in most adults. Sports nutrition groups such as the International Society of Sports Nutrition cite higher ranges for people who train regularly. Your ideal amount depends on your body, activity, age, and health, so a provider or registered dietitian can help you set a target.
Complete vs incomplete protein
A complete protein contains all nine essential amino acids in useful amounts. Most animal proteins and soy are complete. Many plant proteins are lower in one or more essential amino acids, which is why combining sources (like beans and grains) helps. Collagen is notable for being incomplete: it lacks tryptophan.
Does timing matter?
Research suggests total daily protein matters most. Spreading protein across meals, and including some after training, may help, but it's a smaller effect than simply eating enough.
Quality markers
- Leucine content: a key trigger for muscle building. Whey, dairy, and meat are high in it.
- Digestibility: how much of the protein your body actually absorbs.
- Completeness: whether all nine essential amino acids are present.