Close Menu
    Subscribe

    Amino Acids 101

    Amino Acids 101:

    What You Need to Know

    At RxGainz, our mission is to make supplements simple. Here’s your go-to guide on amino acids — what they are, who needs them, how to use them, and the pros and cons.

    What Are Amino Acids?

    Amino acids are the building blocks of protein.

    Your body uses ~20 amino acids.

    • Essential Amino Acids (EAAs): must come from diet or supplements.
    • Non-Essential: your body can produce them.
    • Conditional: needed in times of stress, illness, or injury.

    It helps regenerate ATP (the cell’s “energy currency”) during short bursts of high-intensity activity.

    Food Equivalents: EAAs vs. Whole Foods

    Here’s how a serving of EAAs compares to common protein foods in terms of essential amino acid delivery (not calories):

    • 1 serving of EAAs (~10 g powder, ~8–9 g active amino acids) ≈ the essential amino acid content of:
        • 1 whole egg (6–7 g protein, 3.5–4 g EAAs)
        • 3 oz chicken breast (~25 g protein, ~11–12 g EAAs)
        • 1 scoop whey protein (~20–25 g protein, ~10–12 g EAAs)

    👉 Translation: a single scoop of EAAs can give you the same muscle-building essentials as an egg or a small portion of chicken — but with almost no calories and no digestion burden.

    EAAs, Calories, and Fasting

    This is one of the biggest questions we get: Can you take EAAs while fasting?

    • Yes, you can. Essential amino acid supplements contain virtually no calories (≈4 calories per gram, but servings are small and usually <40 calories total). They are not metabolized like whole protein foods because they don’t come with fats, carbs, or large calorie loads.

    • Many experts and athletes use EAAs during intermittent fasting because they don’t significantly spike insulin or “break the fast” in the way a meal would.

    • EAAs deliver the raw materials for muscle repair without the calories that come from eating a full protein source.

    Who Should Consider Amino Acids?

    Supplements may help if:

    • Athletes & Lifters: speed recovery and reduce soreness.

    • Older Adults: prevent muscle loss with age.

    • During Illness, Surgery, or Injury: preserve lean mass.

    • Low Protein Diets: vegans, vegetarians, or anyone eating less protein.

    • Intermittent Fasters: EAAs give muscle support during fasts without breaking them.

    How & When to Use Them

    Types:

    • EAAs: complete formulas, best overall support.

    • BCAAs: leucine, isoleucine, valine (subset of EAAs).

    • Single Amino Acids: targeted (glutamine, arginine, β-alanine, tryptophan).

    Timing:

    • Pre- or Intra-Workout (especially if training fasted).

    • Post-Workout for recovery.

    • Between meals if protein intake is low.

    Benefits

    • Muscle repair & growth

    • Faster recovery & less soreness

    • Support during fasting, dieting, or illness

    • Helps preserve lean mass

    • May support mood, sleep, or blood sugar

    Risks & Drawbacks

    • Digestive upset (bloating, nausea, cramps)

    • Overuse can create imbalances

    • Should be avoided or monitored in kidney/liver disease

    • Long-term high-dose safety not fully known

    • Quality varies — always look for third-party tested supplements

    Discover Recommended Products

    Coming Soon
    RXGainz Amino Acids

    Coming Soon

    Coming Soon
    RXGainz Amino Acids

    Coming Soon

    Best Practices

    • Food first: prioritize high-quality protein.

    • Use EAAs strategically — fasting, training, recovery.

    • Stick to recommended dosages (10–15 g EAAs per serving is common).

    • Choose clean, tested products (NSF, Informed-Sport, USP).

    • Consult your doctor if you have medical conditions or take medications.

    Sources

    Cleveland Clinic, Healthline, NIH, PubMed clinical reviews, WebMD, MedicineNet.