Essential Amino Acids (EAA): Benefits, Dose and EAA vs BCAA
Essential amino acids (EAAs) are the nine amino acids your body cannot make, so they must come from food. In short lab tests, a few grams raise muscle protein building for a few hours. Trials that lasted months are mixed. If you buy a powder, look for 6 g or more of the nine in a serving.
What EAAs are
- The nine. Histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan and valine. Your body makes the other amino acids itself.
- Where you get them. Food protein: meat, fish, eggs, dairy, soy and other beans. An EAA powder gives you the nine without the rest of the protein.
- BCAAs are three of the nine (leucine, isoleucine and valine). Leucine is the one most studies focus on.
What the research says
Most EAA studies measure muscle protein building in a lab for a few hours after one drink. Fewer follow people for months. Many were in older adults. Here is each study we read, with its dose:
| Study | Dose | What it found |
|---|---|---|
| Wilkinson 201824 older women | 1.5 g (0.6 g leucine) | Raised muscle protein synthesis about as much as 6 g of the same mix or 40 g of whey, over the first 2 hoursTies: One author works for Ajinomoto, an amino-acid maker |
| Bukhari 201516 older women, 8 a group | 3 g (40% leucine) | Raised muscle protein synthesis as much as 20 g of whey over the first 2 hours, at rest and after exerciseTies: One author works for Ajinomoto, an amino-acid maker |
| Børsheim 2002Healthy volunteers | 6 g, twice | Taken 1 and 2 hours after strength exercise, it raised net muscle protein balanceTies: Funded by the NIH; PubMed lists no industry tie |
| Katsanos 2006Older and young adults | 6.7 g | In older adults, the mix with 41% leucine raised muscle protein synthesis; the one with 26% leucine (the share in whey) did not. Young adults responded to bothTies: Funded by the NIH; PubMed lists no industry tie |
| Moro 201819 healthy older adults | 6.8 g | A test dose given before and after 12 weeks of strength training raised muscle protein synthesis both times. The training was the treatment, not the EAATies: Funded by the NIH; PubMed lists no industry tie |
| Paddon-Jones 20046 young and 7 older adults | 15 g | Raised muscle protein synthesis in both age groupsTies: Funded by the NIH; PubMed lists no industry tie |
| Park 2020Young adults | 3.2 g EAA plus 2.4 g whey, one or two servings | Per gram, more anabolic than a whey-based recovery drink (the comparison, not a placebo)Ties: The senior author has a pending patent on the mix tested |
| Trial | Dose and length | What it found |
|---|---|---|
| Dillon 200914 older women, placebo-controlled | 7.5 g twice a day3 months | Lean mass rose against placebo; strength did not changeTies: Funded by the NIH; PubMed lists no industry tie |
| Jeong 202696 women aged 65 and over, four groups, no placebo drink | 5.5 g twice a day12 weeks | Muscle mass rose significantly in the group that did both strength training and EAAs. The authors found the two together worked better than either one aloneTies: The authors declare no competing interests |
| Kim 2021130 women over 65, placebo-controlled; both groups did an exercise class | 3 g a day3 months | No added benefit for muscle mass or strengthTies: Four authors work for Ajinomoto, an amino-acid maker |
| Godard 200217 men over 65 doing strength training | Not given in the abstract (8 amino acids plus sugars)12 weeks | Strength and muscle size rose the same with or without the drinkTies: Funded by the NIH; PubMed lists no industry tie |
| Børsheim 200812 older adults, no placebo group | 11 g with arginine, twice a day16 weeks | Lean mass was up at week 12 (not at week 16), and leg strength roseTies: Funded by the NIH; PubMed lists no industry tie |
- Short term, small doses work in the lab. 1.5 to 15 g raised muscle protein building for a few hours, in young and older adults. Each study’s ties to industry are listed under it.
- Over months, results are mixed. In older women, muscle mass rose significantly in the group that did both strength training and EAAs, and the authors found the two together better than either alone (Jeong 2026; no placebo drink). One small trial found more lean mass but no more strength (Dillon 2009). Two found no added benefit (Kim 2021; Godard 2002).
- Leucine share. In older adults, a 6.7 g dose with 41% leucine raised muscle protein building and one with 26% did not (Katsanos 2006). Even so, 1.5 g with 0.6 g of leucine worked in another test (Wilkinson 2018), so no fixed leucine amount is proven.
How much to take
There is no official dose. The International Society of Sports Nutrition’s position stand (the society’s official position) says 1.5 to 3 g starts muscle protein building at rest, and the effect levels off around 15 to 18 g (Ferrando 2023; several authors have amino-acid industry ties). Trials that ran for months used 3 to 11 g, once or twice a day.
- Our line: 6 g or more of the nine a serving, the size used in common one-dose tests (Børsheim 2002; Katsanos 2006). That line is ours, not an official one. 8 of the 16 products we score reach it.
- Up to about 15 g at once, where the position stand says the effect levels off.
- Count the nine, not the scoop. A 12.9 g scoop of RAW Nutrition EAA Plus, Watermelon Grape holds 9.25 g of the nine. Nutricost EAA Capsules 1200 mg give 1.2 g in 2 capsules. How to read the label.
- Eating less to lose weight? The position stand says EAA needs rise when you eat fewer calories than you burn.
- Over 60? It says older muscles need a larger share of leucine, though no study has compared formulas head to head.
EAA, BCAA or whey
- BCAA. Three of the nine. A 2017 review found no study that measured muscle protein building with BCAAs alone taken by mouth, and called the claim that they raise it unwarranted (Wolfe 2017; the author owns shares in an amino-acid company). But a 2017 trial did measure it: in 10 young men, 5.6 g of BCAAs after strength exercise raised muscle protein building 22% more than a placebo drink over 4 hours (Jackman 2017; NIH-funded, PubMed lists no industry tie). A 2025 crossover trial of 12 adults compared a dileucine-added EAA drink with a BCAA drink: whole-body leucine retention was about equal. Three authors work for the company that developed both drinks (Aguilera 2025).
- Whey. A whole protein with all nine and more. In older women, 3 g of a leucine-rich EAA mix matched 20 g of whey in a 2-hour test (Bukhari 2015). That is a short lab result, not proof of more muscle over months.
- If you already eat protein at meals, an EAA powder is a convenience, not a must. None of the month-long trials above compared an EAA powder with simply eating more protein.
How to read an EAA label
- Grams of the nine. Add up the nine amounts, or find the EAA total. Flavor, sweetener and other amino acids add scoop weight. NAKED EAAs Amino Acids Powder holds 9.25 g of EAA in a 10 g serving (2 scoops).
- All nine, but in what mix? No label we read has equal amounts. On the Nutricost EAA labels, 6 g of the 8 g is the three BCAAs, and methionine is 10 mg.
- Each amount, or one blend? 3 of the 16 we score print only a blend total, so you cannot check the leucine.
- Capsules are small. The 3 capsule products we score give 0.97 g to 5 g a serving. Reaching 6 g takes a handful.
- A testing list? “Third-party tested” on a bottle is the brand’s claim. Check the list itself (below).
Which EAA is third-party tested
Of the 16 EAA products we score, 7 are on a public testing list, and 6 of those are on a list that screens for drugs banned in sport. We searched NSF/ANSI 173, NSF Certified for Sport, Informed Choice and Informed Sport on October 7, 2026; our September 22, 2026 copy of USP’s list holds no EAA product. BulkSupplements is on NSF/ANSI 173; NSF Certified for Sport lists only its 1 kg bag. Each product and its list.
Which EAA to buy
Our pick, BulkSupplements Essential Amino Acids Powder, is near the top of the page. If you are drug-tested in your sport, the first row is our athlete pick. The others are popular EAA powders and capsules, with what 10 g of the nine costs at list price:
- Buy RAW Nutrition EAA Plus, Watermelon Grape (30 Servings) on Amazon
- Buy Nutricost EAA Powder, Unflavored (30 Servings) on Amazon
- Buy NAKED EAAs Amino Acids Powder (500 g, Unflavored, Vegan) on Amazon
- Buy Nutricost EAA Powder, Fruit Punch (30 Servings) on Amazon
- Buy Nutricost EAA Capsules 1200 mg (240 ct) on Amazon
See all 16 we score, with each score, cost and testing list.
EAA guides
Which product
Testing
On this page
Safety
- No national upper limit. No national health agency has set an upper limit for amino acids, says a 2023 review of studies run by the International Council on Amino Acid Science, a nonprofit group. The review proposes limits for some single amino acids (Elango 2023). The ISSN position stand says the safe upper limit leaves room for supplements in most healthy people (Ferrando 2023).
- Ask your doctor first if you have a health condition that limits protein or amino acids, take a medicine, or are pregnant.
How we checked this
Products. We read 28 EAA products and could score 16. Scores updated October 7, 2026. Every score, and why some are not scored.
Studies. Every study here was read on PubMed. Doses and results are as each abstract states them. Ties to industry come from each PubMed record’s conflict-of-interest statement, author addresses and grant list.
Testing lists. NSF/ANSI 173, NSF Certified for Sport, Informed Choice and Informed Sport, read in full on October 7, 2026. USP’s list comes from our copy of September 22, 2026.
Prices. Each brand’s own list price for one pack, checked October 7, 2026. Amazon’s price can differ.
Sources
- Wilkinson DJ 2018, Clin Nutr. PubMed 29031484
- Bukhari SS 2015, Am J Physiol Endocrinol Metab. PubMed 25827594
- Børsheim E 2002, Am J Physiol Endocrinol Metab. PubMed 12217881
- Katsanos CS 2006, Am J Physiol Endocrinol Metab. PubMed 16507602
- Moro T 2018, J Nutr. PubMed 29796648
- Paddon-Jones D 2004, Am J Physiol Endocrinol Metab. PubMed 14583440
- Park S 2020, J Int Soc Sports Nutr. PubMed 32041644
- Dillon EL 2009, J Clin Endocrinol Metab. PubMed 19208731
- Jeong D 2026, J Int Soc Sports Nutr. PubMed 41863133
- Kim H 2021, Aging Clin Exp Res. PubMed 32978751
- Godard MP 2002, Med Sci Sports Exerc. PubMed 12131252
- Børsheim E 2008, Clin Nutr. PubMed 18294740
- Ferrando AA 2023, J Int Soc Sports Nutr. PubMed 37800468
- Wolfe RR 2017, J Int Soc Sports Nutr. PubMed 28852372
- Jackman SR 2017, Front Physiol. PubMed 28638350
- Aguilera JA 2025, J Int Soc Sports Nutr. PubMed 41321015
- Elango R 2023, Adv Nutr (upper limits for amino acids; reviews studies run by the International Council on Amino Acid Science). PubMed 37062432
- Testing lists: NSF/ANSI 173, NSF Certified for Sport, Informed Choice and Informed Sport, read October 7, 2026; USP Verified from our copy of September 22, 2026. Labels: each brand’s page or the NIH Dietary Supplement Label Database. Prices: each brand’s own list price, checked October 7, 2026.
This page is for information. It is not medical advice.