OnePin Peptide Library · Metabolic
Essential Amino Acids (EAAs)
EAA · EAAs
Essential amino acids (EAAs) are the nine amino acids that humans cannot synthesize and must obtain from diet: leucine, isoleucine, valine (the three branched-chain amino acids - BCAAs), lysine, methionine, phenylalanine, threonine, tryptophan, and histidine. EAAs are the rate-limiting substrates for muscle protein synthesis (MPS), tissue repair, and synthesis of neurotransmitters and other amino acid-derived compounds.,EAA supplements (typically 5-15g per serving) provide free-form essential amino acids in optimal ratios for MPS, with absorption rates of 30-60 minutes (faster than intact protein). They are used by athletes for muscle building/recovery, by older adults for sarcopenia prevention, by those with low total protein intake, and by users wanting protein effects without the calories of whey/casein. PerfectAmino (BodyHealth) is one of the most-marketed brands, claiming 99% utilization vs ~30-40% for whey - a controversial claim.,The key controversy: EAAs are necessary, but the 'high utilization rate' claims (99%) are based on a non-standard 'Net Nitrogen Utilization' calculation. Standard biochemical analysis shows EAA supplements ARE more efficiently used than incomplete proteins, but the 99% figure is overstated. For most users, eating adequate complete protein (whey, eggs, meat) provides EAAs adequately. EAA supplements are most useful for: (1) older adults with reduced appetite, (2) athletes wanting low-calorie amino support during cuts, (3) those with absorption issues, (4) intra-workout supplementation.
Pre/intra/post-workout for athletic use. Between meals for older adults to maintain MPS triggers throughout day. Fasted training: useful intra-workout to prevent muscle breakdown without breaking fast (minimal calories). Mix in cool water - bitter taste is common.
Start here. Every protocol below is ordered lowest-first. Begin at the smallest effective dose, hold about a week to assess tolerance, and step up only if needed.
How it works
Leucine triggers MPS via mTOR/p70S6K activation - the same mechanism as whey but delivered as free leucine without need for proteolytic digestion. ~3g leucine per serving optimally triggers MPS.,All 9 EAAs are required for actual protein synthesis to occur after MPS is triggered - leucine starts the signal, but lysine, methionine, threonine, etc. are needed as building blocks. This is why pure leucine alone is suboptimal vs full EAA blend.,Free amino acid absorption: EAAs in free form bypass gastric digestion and are rapidly absorbed in upper small intestine via amino acid transporters (LAT1, B0AT1, others). Plasma amino acid levels rise within 30-60 minutes (vs 60-90 min for whey, 90-120 min for whole protein).,Nitrogen efficiency: EAA blends have higher nitrogen retention efficiency than mixed proteins because they contain only essential amino acids - no 'wasted' non-essentials. This is particularly relevant in protein-restricted contexts (kidney disease, fasting).,Branched-chain prominence: EAA blends are typically 40-50% BCAAs by mass (with leucine 20-25%, isoleucine and valine ~10% each). The remaining 50-60% are the other 6 EAAs in roughly proportional amounts.,Insulin response: EAAs cause less insulin spike than whey (which contains rapidly absorbed peptides and lactose). Useful for intra-workout where insulin spike isn't desired.,Substrate for neurotransmitters: tryptophan → serotonin, phenylalanine → catecholamines, methionine → SAMe. EAA blends provide these precursors.
Leucine triggers MPS via mTOR/p70S6K activation - the same mechanism as whey but delivered as free leucine without need for proteolytic digestion. ~3g leucine per serving optimally triggers MPS.,All 9 EAAs are required for actual protein synthesis to occur after MPS is triggered - leucine starts the signal, but lysine, methionine, threonine, etc. are needed as building blocks. This is why pure leucine alone is suboptimal vs full EAA blend.,Free amino acid absorption: EAAs in free form bypass gastric digestion and are rapidly absorbed in upper small intestine via amino acid transporters (LAT1, B0AT1, others). Plasma amino acid levels rise within 30-60 minutes (vs 60-90 min for whey, 90-120 min for whole protein).,Nitrogen efficiency: EAA blends have higher nitrogen retention efficiency than mixed proteins because they contain only essential amino acids - no 'wasted' non-essentials. This is particularly relevant in protein-restricted contexts (kidney disease, fasting).,Branched-chain prominence: EAA blends are typically 40-50% BCAAs by mass (with leucine 20-25%, isoleucine and valine ~10% each). The remaining 50-60% are the other 6 EAAs in roughly proportional amounts.,Insulin response: EAAs cause less insulin spike than whey (which contains rapidly absorbed peptides and lactose). Useful for intra-workout where insulin spike isn't desired.,Substrate for neurotransmitters: tryptophan → serotonin, phenylalanine → catecholamines, methionine → SAMe. EAA blends provide these precursors.
What to expect
Acute: amino acid availability, MPS spike.
Evidence
Interactions & stacking
What's safe to combine, and what belongs in a separate pin.
Safe & synergistic
Keep separate
Pharmacokinetics
Storage. Store at room temperature (20-25C) in a cool, dry place. Protect from moisture. Powder shelf-stable 1-2 years. Capsules longer.
Regulatory status
Classified as a dietary supplement / food product in the US - no prescription required. Specialized medical formulations for PKU, MSUD, and other inborn errors are prescription medical foods.
Put it to work
Calculate, log & track
Open Essential Amino Acids (EAAs) straight into OnePin with your vial and dose pre-filled, then let it handle the syringe math and remind you before the vial runs out.
Open Essential Amino Acids (EAAs) in the app →Go deeper
The guide & community
The complete Essential Amino Acids (EAAs) walkthrough, real protocol discussion and coaching live inside the BlessUp community on Skool.
Join the community ↗