PlainVitamins

Thyroid Naturals

by Optimal Naturals · capsule · 60 capsules

  • Off the market since October 2023 (NIH)
  • DSLD label 20122
  • Serving 1 capsule; amounts per 2 capsules

Thyroid Naturals by Optimal Naturals lists 13 ingredients, 13 with an amount per serving of 2 capsules, such as 100 mcg of vitamin B12, 150 mcg of iodine, 200 mg of magnesium and 8 mg of zinc. Its current label entered the NIH Dietary Supplement Label Database on March 25, 2013.

What is in Thyroid Naturals?

Each row as the label prints it, per serving of 2 capsules. 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).

Thyroid Naturals: Supplement Facts rows against the market (DSLD label 20122, January 2026 release)
IngredientAmount% DVAmong products listing it
Vitamin B12as Cyanocobalamin100 mcg1,667%Vitamin B12 in Thyroid Naturals against 14,425 products100 mcg per serving; the middle half of products list 6 mcg to 200 mcg, the median 36 mcg.DV 2.4 mcg100 mcg

Higher than 61% of 14,425 products listing vitamin B12 (median 36 mcg). Per day at the most servings: 200 mcg.

Iodineas KelpIodine (Form: from Kelp)150 mcg100%Iodine in Thyroid Naturals against 6,382 products150 mcg per serving; the middle half of products list 75 mcg to 150 mcg, the median 150 mcg.DV 150 mcgUL 1,100 mcg150 mcg

15% of 6,382 products listing iodine give more (median 150 mcg). Per day at the most servings: 300 mcg.

Magnesiumas Magnesium Oxide200 mg50%Magnesium in Thyroid Naturals against 14,003 products200 mg per serving; the middle half of products list 30 mg to 200 mg, the median 86 mg.UL 350 mgDV 420 mg200 mg

Higher than 75% of 14,003 products listing magnesium (median 86 mg). Per day at the most servings: 400 mg. 1.1 times the adult UL a day.

Zincas Zinc Oxide8 mg53%Zinc in Thyroid Naturals against 13,186 products8 mg per serving; the middle half of products list 5 mg to 15 mg, the median 11 mg.DV 11 mgUL 40 mg8 mg

60% of 13,186 products listing zinc give more (median 11 mg). Per day at the most servings: 16 mg.

Seleniumas Selenium Amino Acid Chelate200 mcg286%Selenium in Thyroid Naturals against 7,658 products200 mcg per serving; the middle half of products list 27 mcg to 100 mcg, the median 55 mcg.DV 55 mcgUL 400 mcg200 mcg

Higher than 82% of 7,658 products listing selenium (median 55 mcg). Per day at the most servings: 400 mcg.

Copperas Copper Oxide200 mcg10%Copper in Thyroid Naturals against 6,468 products0.2 mg per serving; the middle half of products list 0.5 mg to 2 mg, the median 1 mg.DV 0.9 mgUL 10 mg0.2 mg

88% of 6,468 products listing copper give more (median 1 mg). Per day at the most servings: 0.4 mg.

Manganeseas Manganese Amino Acid Chelate2 mg100%Manganese in Thyroid Naturals against 7,016 products2 mg per serving; the middle half of products list 1 mg to 3.92 mg, the median 2 mg.DV 2.3 mgUL 11 mg2 mg

38% of 7,016 products listing manganese give more (median 2 mg). Per day at the most servings: 4 mg.

Molybdenumas Molybdenum Amino Acid Chelate50 mcg67%Molybdenum in Thyroid Naturals against 4,390 products50 mcg per serving; the middle half of products list 25 mcg to 75 mcg, the median 50 mcg.DV 45 mcgUL 2,000 mcg50 mcg

41% of 4,390 products listing molybdenum give more (median 50 mcg). Per day at the most servings: 100 mcg.

L-Tyrosine300 mgTyrosine in Thyroid Naturals against 1,680 products300 mg per serving; the middle half of products list 150 mg to 989 mg, the median 500 mg.300 mg

59% of 1,680 products listing tyrosine give more (median 500 mg). Per day at the most servings: 600 mg.

SchizandraSchizandra Genus: Schisandra Note: herb powder240 mgSchisandra in Thyroid Naturals against 460 products240 mg per serving; the middle half of products list 50 mg to 240 mg, the median 108.75 mg.240 mg

Higher than 71% of 460 products listing schisandra (median 108.75 mg). Per day at the most servings: 480 mg.

AshwagandhaAshwagandha PlantPart: root Note: herb powder200 mgAshwagandha in Thyroid Naturals against 1,646 products200 mg per serving; the middle half of products list 125 mg to 500 mg, the median 250 mg.200 mg

51% of 1,646 products listing ashwagandha give more (median 250 mg). Per day at the most servings: 400 mg.

BladderwrackBladderwrack Note: herb powder50 mgBladderwrack in Thyroid Naturals against 188 products50 mg per serving; the middle half of products list 50 mg to 500 mg, the median 77.5 mg.50 mg

55% of 188 products listing bladderwrack give more (median 77.5 mg). Per day at the most servings: 100 mg.

Cayenne PepperCayenne Pepper Note: herb powder30 mgCapsicum in Thyroid Naturals against 874 products30 mg per serving; the middle half of products list 25 mg to 100 mg, the median 44.5 mg.30 mg

57% of 874 products listing capsicum give more (median 44.5 mg). Per day at the most servings: 60 mg.

Source: NIH ODS Dietary Supplement Label Database, label 20122 (entered March 25, 2013), 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:

  • At 2 servings a day, the most its directions give, the label lists 400 mg of magnesium, 1.1 times the adult Tolerable Upper Intake Level.
  • 88% of the 6,468 products that print an amount of copper list more than its 0.2 mg of copper (median 1 mg).

The NIH database records 2 servings 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?

1 product lists the very same ingredients; the nearest amounts come first.

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
SUGGESTED USE: As a dietary supplement, take one (1) capsule in the morning and one (1) capsule in the evening.
Warnings
This product is manufactured and packaged in a facility which may also process milk, soy, wheat, egg, peanuts, tree nuts, fish and crustacean shellfish.
KEEP OUT OF THE REACH OF CHILDREN.
DO NOT USE IF SAFETY SEAL IS DAMAGED OR MISSING.
CAUTION: Do not exceed recommended dose. Do not use in conjunction with other products high in iodine as excessive iodine intake may be harmful.
Pregnant or nursing mothers, children under 18, and individuals with a known medical condition should consult a physician before using this or any dietary supplement.
Storage
STORE IN A COOL, DRY PLACE.

Source: label statements in DSLD label 20122.

What else is on the label?

Other ingredients: Gelatin, Cellulose, Magnesium Stearate, Silicon Dioxide.

How many labels does Thyroid Naturals have?

One label is on file, entered on March 25, 2013.

  1. Label 20122 (current) Entered March 25, 2013 · off the market October 4, 2023 · 60 capsules

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

Who makes it?

The label names Optimal Naturals(TM) (manufacturer), Orange County, California. All Optimal Naturals products.

Where next?