# Eight essential amino acids: why the complete profile decides

> Protein synthesis follows the weakest-link principle - one missing amino acid slows everything down. What research shows about EAAs, leucine and absorption kinetics, and how WOO® Amino is set up.

Of the twenty amino acids our body uses to build proteins, it can produce twelve on its own. Eight it cannot. Those eight have to come from food - every day, in sufficient quantity and in the right ratio. If a single one is missing, the entire protein synthesis stalls.

## Why "essential" is meant literally

Protein synthesis follows the weakest-link principle. The ribosome complex assembles an amino acid chain building block by building block - if the threonine needed at position 47 is missing, the process breaks off. This is the so-called **limiting amino acid principle**, established in nutritional science since the 1950s.

In practice: if one essential amino acid is scarce in a meal containing 30 g of protein, only the portion up to that limit is used - the rest is oxidised. The amino acid profile of a protein source therefore matters more than the gram count on the packaging.

## Leucine as a signalling molecule, not just a building block

Among the essential amino acids, **leucine** plays a special role. It is not only building material but a signalling molecule: leucine activates the mTORC1 pathway in the muscle cell and thereby actively switches on muscle protein synthesis. Work by Churchward-Venne and colleagues shows that a leucine pulse of roughly 2 to 3 g per meal measurably triggers synthesis.

The context matters: leucine alone is not enough. In a widely cited analysis from 2017, Wolfe showed that isolated BCAA intake without the remaining essential amino acids cannot sustainably increase synthesis - there is simply no building material. The signal needs the full construction site.

## Free amino acids and the kinetics of absorption

Free amino acids do not need to be digested. They pass the stomach quickly and appear in the blood within 15 to 30 minutes - considerably faster than amino acids from an intact protein that first has to be broken down enzymatically. As early as 1999, Tipton and colleagues showed that orally administered amino acids after resistance training produce a positive net protein balance.

This kinetic profile is the real reason to use an amino acid powder: not as a replacement for protein from food, but for moments when a swift rise in the blood is desirable.

## How WOO® Amino puts this into practice

**[WOO® Amino](/en/shop/woo-amino-can)** contains all eight essential amino acids in free form, with a BCAA complex as its base. Each 7 g serving provides 1200 mg L-leucine, 800 mg L-valine and 600 mg L-isoleucine, plus 900 mg L-lysine, 450 mg L-threonine, 330 mg L-methionine, 300 mg L-histidine and 120 mg L-tryptophan. The profile is therefore not reduced to BCAAs but complete - precisely the point research describes as decisive.

One sachet is stirred into 300 ml of water: after training, or as a protein supplement alongside a meal. The powder is vegan, lactose- and gluten-free, passion fruit flavour. For protein, the authorised claim applies that it contributes to the maintenance and growth of muscle mass and to the maintenance of normal bones.

## Frequently asked questions

**Does an amino acid powder replace a protein meal?**
No. Food supplements are not a substitute for a balanced diet. It makes sense where a full meal is impractical - for instance directly after a session - or when the diet is one-sided.

**How do EAAs differ from BCAAs?**
BCAAs are three branched-chain amino acids: leucine, isoleucine and valine. EAAs comprise all eight essential ones. Since protein synthesis requires all eight, a complete profile is functionally superior to a pure BCAA product.

**When is the best time to take it?**
The evidence shows that total daily intake matters more than exact timing. In practice, taking it after training or spread across the day with meals has proven effective.

## Sources

Wolfe RR (2017), Journal of the International Society of Sports Nutrition - Branched-chain amino acids and muscle protein synthesis in humans: myth or reality?
Churchward-Venne TA et al. (2012), Journal of Physiology - Nutritional regulation of muscle protein synthesis with resistance exercise.
Tipton KD et al. (1999), American Journal of Physiology - Postexercise net protein synthesis in human muscle from orally administered amino acids.

*WOO® Amino in the NEMAPO shop.*