PlainVitamins

Daily Amino Acid

by 21st Century · tablet or pill · 120 tablets

  • On the market (NIH)
  • UPC 7 40985 22557 8
  • DSLD label 258438
  • Serving 1 tablet
  • 120 servings

Daily Amino Acid by 21st Century lists 11 ingredients, 11 with an amount per serving of 1 tablet, such as 150 mg of calcium, 17 mg of L-histidine, 63 mg of L-isoleucine and 105 mg of L-leucine, beside 1 Nutrition Facts row (calories, fat and the like). Its current label entered the NIH Dietary Supplement Label Database on December 18, 2021.

What is in Daily Amino Acid?

Each row as the label prints it, per serving of 1 tablet. The capsule beside an amount places it among every product in the NIH database that lists the same ingredient: the bar is the middle half of their amounts, the line in it the median, the whiskers the 10th and 90th percentiles; the green tick is the FDA Daily Value and the red dashed tick the adult upper limit (IOM).

Daily Amino Acid: Supplement Facts rows against the market (DSLD label 258438, January 2026 release)
IngredientAmount% DVAmong products listing it
Calciumas Calcium Carbonate, Dicalcium Phosphate150 mg12%Calcium in Daily Amino Acid against 17,831 products150 mg per serving; the middle half of products list 50 mg to 252 mg, the median 115 mg.DV 1,300 mgUL 2,500 mg150 mg

Higher than 58% of 17,831 products listing calcium (median 115 mg).

Sodium5 mg1%Sodium in Daily Amino Acid against 14,514 products5 mg per serving; the middle half of products list 15 mg to 142 mg, the median 55 mg.5 mg

89% of 14,514 products listing sodium give more (median 55 mg).

L-Histidineas L-Histidine HydrochlorideL-Histidine (Form: as L-Histidine HCl)17 mgHistidine in Daily Amino Acid against 591 products17 mg per serving; the middle half of products list 50 mg to 402.8 mg, the median 125 mg.17 mg

88% of 591 products listing histidine give more (median 125 mg).

L-Isoleucine63 mgIsoleucine in Daily Amino Acid against 1,614 products0.063 g per serving; the middle half of products list 0.5 g to 1.5 g, the median 1.23 g.0.063 g

95% of 1,614 products listing isoleucine give more (median 1.23 g).

L-Leucine105 mgLeucine in Daily Amino Acid against 2,056 products0.105 g per serving; the middle half of products list 1 g to 3.5 g, the median 2.5 g.0.105 g

93% of 2,056 products listing leucine give more (median 2.5 g).

L-Lysineas L-Lysine HydrochlorideL-Lysine (Form: as L-Lysine HCl)93 mgLysine in Daily Amino Acid against 1,250 products93 mg per serving; the middle half of products list 148.25 mg to 996.25 mg, the median 500 mg.93 mg

83% of 1,250 products listing lysine give more (median 500 mg).

DL-Methionine21 mgDL-Methionine in Daily Amino Acid against 151 products21 mg per serving; the middle half of products list 25 mg to 132.5 mg, the median 50 mg.21 mg

79% of 151 products listing DL-methionine give more (median 50 mg).

L-Cysteineas L-Cysteine Hydrochloride11 mgCysteine in Daily Amino Acid against 516 products11 mg per serving; the middle half of products list 30 mg to 200 mg, the median 85 mg.11 mg

84% of 516 products listing cysteine give more (median 85 mg).

L-Phenylalanine32 mgPhenylalanine in Daily Amino Acid against 611 products32 mg per serving; the middle half of products list 100 mg to 597.5 mg, the median 250 mg.32 mg

90% of 611 products listing phenylalanine give more (median 250 mg).

L-Tyrosine31 mgTyrosine in Daily Amino Acid against 1,680 products31 mg per serving; the middle half of products list 150 mg to 989 mg, the median 500 mg.31 mg

93% of 1,680 products listing tyrosine give more (median 500 mg).

L-Threonine69 mgTHREONINE in Daily Amino Acid against 590 products69 mg per serving; the middle half of products list 140 mg to 886.25 mg, the median 500 mg.69 mg

82% of 590 products listing THREONINE give more (median 500 mg).

L-Valine58 mgValine in Daily Amino Acid against 1,632 products0.058 g per serving; the middle half of products list 0.5 g to 1.5 g, the median 1.25 g.0.058 g

95% of 1,632 products listing valine give more (median 1.25 g).

Source: NIH ODS Dietary Supplement Label Database, label 258438 (entered December 18, 2021), version 9.4.0. See the label on DSLD. Amounts are what the maker printed; DSLD does not test products. Daily Values: the FDA's Daily Value page.

Is that a lot?

The rows in the top or bottom tenth of the products that list the same ingredient, and any above the adult upper limit at the most servings a day the directions give:

  • 95% of the 1,614 products that print an amount of isoleucine list more than its 0.063 g of L-isoleucine (filed by NIH under isoleucine) (median 1.23 g).
  • 93% of the 2,056 products that print an amount of leucine list more than its 0.105 g of L-leucine (filed by NIH under leucine) (median 2.5 g).
  • 90% of the 611 products that print an amount of phenylalanine list more than its 32 mg of L-phenylalanine (filed by NIH under phenylalanine) (median 250 mg).
  • 93% of the 1,680 products that print an amount of tyrosine list more than its 31 mg of L-tyrosine (filed by NIH under tyrosine) (median 500 mg).
  • 95% of the 1,632 products that print an amount of valine list more than its 0.058 g of L-valine (filed by NIH under valine) (median 1.25 g).

The NIH database records one serving a day from the label's directions; its % Daily Values are for adults and children 4 or more years of age. The directions as printed are further down this page.

The Tolerable Upper Intake Level is the most of a nutrient per day, from food, water and supplements together, that is likely to pose no risk for almost all adults (Institute of Medicine, 2011). It does not apply under medical supervision. This page compares labels; it is not medical advice.

Sources: amounts from the DSLD label; Daily Values from 21 CFR 101.9(c)(8)(iv); adult upper limits from the Institute of Medicine's DRI summary tables (2011). How positions are computed.

Which products have the closest formulas?

The products whose ingredient lists overlap most with Daily Amino Acid's, rare ingredients counting for more.

Source: ingredient lists of every product's current label in DSLD (version 9.4.0); similarity weights each shared ingredient by how rare it is.

What does the label say about taking it?

Quoted from the label as DSLD transcribed it: the maker's words, including any claim about what the product does, which the FDA has not evaluated and PlainVitamins does not endorse.

Directions
Directions: As a dietary supplement, adults take one (1) tablet daily with any meal or as directed by a healthcare provider. Do not exceed recommended dosage. Individual results may vary.
Warnings
Warning: Consult a healthcare provider prior to use if pregnant, nursing, on medications, have a medical condition or are planning a medical procedure.
Stop use and contact a physician if adverse reactions occur.
Keep out of reach of children.
Do not use if product appears to be tampered with or seal is broken.
Do not exceed recommended dosage.
Contains milk (whey).
Allergens and what it does not contain
No added sugar, yeast, preservatives, artificial flavors or colors.
Gluten free
Storage
Store at room temperature.

Source: label statements in DSLD label 258438.

What else is on the label?

Other ingredients: Whey, Cellulose, Stearic Acid, Croscarmellose Sodium, Magnesium Silicate, Magnesium Stearate, PEG, Polysorbate, Polyvinyl alcohol, Silicon Dioxide.

Seals and symbols as the label prints them (the maker's; a certifier's own list confirms a seal): Guaranteed Quality Laboratory Tested.

How many labels does Daily Amino Acid have?

2 labels are on file under this name since August 23, 2020: other sizes, label designs and reformulations. The current one leads this page.

  1. Label 258438 (current) Entered December 18, 2021 · on the market · 120 tablets · UPC 7 40985 22557 8
  2. Label 233418 Entered August 23, 2020 · off the market August 6, 2021 · 120 tablets · UPC 7 40985 22557 8

DSLD also links this label to: Maximum Strength Daily Amino Acid (image difference, same product).

Source: DSLD label entry and market events, version 9.4.0 (labels entered through September 25, 2025).

Who makes it?

The label names 21st Century HealthCare, Inc. (manufacturer), Tempe, AZ. All 21st Century products.

Where next?