AMINO ACID SUPPLEMENTS offer a tempting promise: You can build more muscle just by stirring them into your smoothie, coffee, or water. That sounds way easier than searing salmon or grilling chicken breast, but are aminos supplements just as good? And what makes amino acid supplements different than regular ol’ protein powder?
The answer depends on what your diet looks like—and which supplement you choose.
What Are Amino Acid Supplements?
Amino acids are organic compounds that build and repair proteins in your body.
When you exercise, you damage proteins that help your muscles contract. “To repair, they need building blocks,” says Arny Ferrando, PhD, a professor at the University of Arkansas Center for Translational Research in Aging and Longevity. Imagine the walls of a house ravaged by a tornado. They’re like your tattered muscle proteins. Amino acids are like the cinder blocks you use to reconstruct the wall.
There are 20 amino acids in food, and nine of them (if you’re curious: leucine, isoleucine, valine, histidine, lysine, methionine, phenylalanine, threonine, and tryptophan) are essential. That means you must eat them, either from food or supplements. Your body can make the other 11 from the nine essential aminos.
Amino acid supplements come in many varieties. Branched-chain amino acids (BCAAs), a popular workout companion, contain three essential aminos: leucine, isoleucine, and valine. Research suggests that eating foods or supplements with all nine essential amino acids is better than supplementing with BCAAs alone because you need all nine essential amino acids to build muscle.
Essential amino acid supplements contain all nine essential aminos, and sometimes nothing more. Check the label, though, because every formula is different. Some amino acid supplements also contain other ingredients, like non-essential aminos, electrolytes, or caffeine.
Who Should Take Amino Acid Supplements?
“Supplements can be beneficial if you're not able to consume sufficient protein from your diet,” says Brad Schoenfeld, PhD, CSCS, CSPS, FNSCA, a professor of exercise science at Lehman College.
Ideally, you need between 1.6 and 2 grams of protein per kilogram of your body weight per day, says Schoenfeld. So if you’re cutting calories to lose weight, and your meal plan falls short of your protein target, an essential amino acid supplement could help. The challenge is that many amino acid supplements do not list how much protein they contain per serving.
However, there’s a hack to help calculate how much protein an aminos supplement provides. Check the Nutrition Facts Panel, add up the total essential amino acids in grams per serving, and then double it. That's how many grams of protein the supplement contains. (Doubling the number helps you account for the fact that food sources of high-quality protein are usually about half essential amino acids.)
If all that sounds like a complete hassle, also know that amino acid supplements present another challenge: They very often don’t contain other essential nutrients found in whole foods, says Schoenfeld
“Usually, when you're eating good protein-rich foods, there are other micronutrients that you're getting in combination with them, which you don't generally get from supplements,” he says. Examples: the blood-supporting iron in that chicken or the anti-inflammatory omega-3 fatty acids in that salmon.
Whether you add supplements or solely eat protein in food, there’s no point in exceeding 2 grams per kilogram per day, says Schoenfeld. "Once you have consumed enough protein to support your daily needs, if you consume more protein, your body is just going to oxidize those amino acids and use them as a fuel source in general, so there's no added benefit.”
When Is the Best Time to Take Amino Acid Supplements?
The best time to take an amino acid supplement is within an hour before or after working out, says Ferrando. The reason: When you take essential amino acid supplements (also called "free-form amino acids “) they do not require digestion and will rapidly move from the stomach to the blood, he says. Up to 15 grams before a workout, at just 60 calories, can help boost blood levels of essential amino acids so they’re available for muscle building.
How Are Amino Acid Supplements Different From Protein Shakes?
Many protein powders have all nine essential amino acids, so they can help you consume the full spectrum. But some have more essential amino acids than others. Animal-derived proteins such as whey protein (43% essential amino acids) and casein (34%) have the most. Pea protein has 30% essential amino acids.
Collagen, another popular protein supplement, lacks the essential amino acid tryptophan. It’s mostly non-essential amino acids.
Ferrando says the amino acids in protein protein can take longer to digest than a standalone essential amino acid supplement. If you’re looking for overall muscle maintenance, that might not matter. If you’re looking for an acute pre-workout muscle boost, it might.
How Do I Choose an Amino Acid Supplement?
Select a product with all nine essential amino acids: leucine, isoleucine, valine, histidine, lysine, methionine, phenylalanine, threonine, and tryptophan.
Make sure it’s tested and certified by a third party, such as NSF or Informed Choice, so you know what’s inside matches what’s listed on the label.
You can add amino acids to smoothies, water, hot drinks—just don’t bake them. The combination of high heat and time would damage the aminos, says Ferrando.
Essential amino acids tend to taste bitter unless enhanced with flavoring, so they might not be appetizing in coffee, says Ferrando. (Collagen, which is flavorless, might be a better protein boost for your morning brew despite its weaker amino acid profile.)
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Julie Stewart
Contributing Writer
Julie Stewart is a writer, editor and content strategist with over a decade of experience translating complex topics — health and medicine, science and engineering — into engaging, accessible stories. Her work has appeared in publications like Men’s Health, Women’s Health, AARP The Magazine, EatingWell and Prevention, and she has also led strategic communications for a top engineering college and a global oncology company.
