FDA Rules for Vitamin D Supplements: Supplement Facts, Daily Value, Tolerances and Claims

How the FDA regulates vitamin D supplements

DSHEA and the dietary supplement framework

The Dietary Supplement Health and Education Act of 1994 (DSHEA) defined dietary supplements, added specific labelling requirements and provided for optional labelling statements. On 23 September 1997 the FDA implemented DSHEA with regulations on the statement of identity, nutrition labelling, ingredient labelling, and nutrient content and health claims for supplements.^[9]

The FDA does not approve dietary supplements or their structure/function claims before sale. The firm is responsible for a safe product, a truthful label and substantiation for every claim.^[8] If a formula contains a new dietary ingredient (NDI), the manufacturer or distributor must notify the FDA at least 75 days before introducing it into interstate commerce, with the evidence that it will reasonably be expected to be safe.^[10] Check the status of every ingredient in the formula, not only the vitamin D, and see our guide to FDA food facility registration for the facility side of a US launch.

What changed for vitamin D in the 2016 labelling rule

The FDA’s final rule “Revision of the Nutrition and Supplement Facts Labels” (81 FR 33742, 27 May 2016) took effect on 26 July 2016. Before it, the regulations required vitamin D to be labelled in International Units (IU). The rule made micrograms (mcg) mandatory, with IU optional, and set the Daily Value for vitamin D at 20 mcg, based on the Recommended Dietary Allowance for the oldest adults.^[6] That RDA is 800 IU a day for people aged 71 and older, against 600 IU for ages 1 to 70.^[3]

The rule’s original compliance dates were 26 July 2018 for manufacturers with US$10 million or more in annual food sales and 26 July 2019 for smaller ones.^[6] A 2018 rule (83 FR 19619) extended them to 1 January 2020 and 1 January 2021.^[12][7] Both dates have passed, so every vitamin D supplement on the US market must now follow the updated format.

Table 1. Vitamin D labelling before and after the 2016 rule

One caution: the FDA’s Dietary Supplement Labeling Guide dates from April 2005 and predates the 2016 rule, so check unit and Daily Value examples against the current eCFR text.^[9][1]

Supplement Facts label requirements for vitamin D

Under 21 CFR 101.36, vitamin D is one of the core dietary ingredients that must be declared in the Supplement Facts panel whenever a serving contains more than the amount that can be declared as zero. It is listed in the set order of vitamins and minerals (vitamin A, vitamin C, vitamin D, vitamin E and so on), and its percent Daily Value must be shown.^[1]

mcg vs IU and Daily Value percentages

Declare the amount in mcg. You may add IU, but only in parentheses after the mcg figure.^[1] Because the 20 mcg Daily Value corresponds to the 800 IU RDA, 1 mcg equals 40 IU.^[2][3] The percent Daily Value is the amount in mcg divided by 20, multiplied by 100: a 50 mcg (2,000 IU) softgel is 250% DV.^[2]

The 20 mcg value applies to adults and children aged 4 and older. Products for other groups use other Daily Values: 10 mcg for infants through 12 months, and 15 mcg for children aged 1 to 3 and for pregnant and lactating women.^[2]

Table 2. Percent Daily Value for common vitamin D strengths (adults and children 4+)

Exemptions

21 CFR 101.36(h) carries over three exemptions from the food rules: small retailers under the sales thresholds in 101.9(j)(1), low-volume products for which a notice is filed under 101.9(j)(18), and bulk supplies shipped for further manufacture or repacking. The first two are lost if the label, labelling or advertising gives nutrition information or makes a nutrient content or health claim, so check eligibility before relying on one.^[1]

Label tolerances and overage

FDA checks compliance on a composite of 12 consumer packages, or 10% of the packages in the lot, whichever is smaller, selected at random.^[1] Vitamin D added to a supplement is a Class I (added) nutrient, so the composite must contain at least the amount declared on the label. Class II (naturally occurring) nutrients must reach at least 80% of the declared value.^[2]

These tolerances are one-sided. The 120% ceiling in 21 CFR 101.9(g)(5) applies to calories, sugars, fats, cholesterol and sodium, not vitamins. For vitamins, 101.9(g)(6) says reasonable excesses over the labelled amount are acceptable within current good manufacturing practice.^[2] The declared amount is therefore a floor that must hold until the end of shelf life, and setting the margin above it is a stability question. Our vitamin D overage guide covers how to set it; the UAE takes a different approach with an 80–120% window, explained in our UAE label claim and overage article.

Structure/function claims: supplements vs disease claims

A structure/function claim describes the role of a nutrient in the normal structure or function of the body, such as the FDA’s example “calcium builds strong bones”. These claims are not pre-approved. The firm must have substantiation that the claim is truthful and not misleading, and must notify the FDA no later than 30 days after first marketing the product with the claim.^[8][4]

The required FDA disclaimer

Every structure/function claim must be accompanied by this disclaimer: “This statement has not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.” A plural version is allowed when there are several claims. The disclaimer must sit next to the claim or be linked to it by a symbol such as an asterisk; it must be boxed when not adjacent, in bold type at least 1/16 inch high.^[4]

In a December 2025 letter the FDA said it intends to use enforcement discretion on the requirement for the disclaimer to appear on each panel that bears a claim, and is likely to propose a rule to amend it. The disclaimer must still appear on the label and be linked to each claim.^[15] No amending rule had been published in the Federal Register by 10 November 2026, so plan labels to the current text of 21 CFR 101.93.

Disease, health and nutrient content claims

A statement that a product prevents, treats or mitigates a disease, such as cancer or heart disease, is a disease claim and makes the product subject to regulation as a drug, unless it is an authorised health claim.^[4] Claims about a classical nutrient deficiency disease, such as rickets, are allowed only if the label also says how widespread the disease is in the United States.^[8] Symbols and pictures can imply a health claim, so heart or organ imagery on a pack needs the same review as the words.^[16]

Two other routes matter for vitamin D. The authorised health claim in 21 CFR 101.72 links adequate calcium, and when appropriate calcium and vitamin D, to a reduced risk of osteoporosis; the product must be “high” in calcium, and “high” in vitamin D to name it in the claim.^[13] Nutrient content claims are defined in 21 CFR 101.54: “high”, “rich in” or “excellent source of” needs at least 20% of the Daily Value per serving, and “good source” 10 to 19%.^[14]

Table 3. Claim types on a US vitamin D supplement

What the largest vitamin D trial does and does not support is set out in our VITAL trial explainer: 2,000 IU a day did not reduce invasive cancer or major cardiovascular events.^[11]

cGMP under 21 CFR Part 111

21 CFR Part 111 sets current good manufacturing practice for manufacturing, packaging, labelling and holding dietary supplements. Firms must establish specifications, including identity, purity, strength and composition specifications for components and the finished product, and determine whether they are met.^[5] Before use, at least one appropriate test or examination must verify the identity of each dietary ingredient.^[5] Our article on a tainted supplement recall shows what happens when identity testing fails.

Reserve samples of each lot of packaged and labelled product must be held for one year past the shelf-life date, if shelf-life dating is used, or for two years from distribution of the last batch.^[5] For vitamin D, strength over shelf life is the specification most likely to be challenged, so link the label claim, the overage and the stability data in one file. How release is checked in the lab is covered in our vitamin D3 dissolution testing walkthrough.

Common labelling mistakes to avoid

• Declaring vitamin D in IU only, or putting IU before mcg.^[1]
• Calculating % DV on a base other than 20 mcg for an adult product, or using 20 mcg on a product for young children or pregnancy.^[2]
• Using disease-prevention wording, including implied claims through heart or organ imagery.^[4][16]
• Missing, unlinked or undersized disclaimers, or no FDA notification within 30 days.^[4]
• Saying “high in vitamin D” below 20% DV.^[14]
• Declaring a potency that stability data cannot support to the end of shelf life.^[2][5]

Getting a vitamin D label right

FDA vitamin D supplement rules come down to five checks: declare vitamin D in mcg with optional IU in parentheses, calculate % DV on the right Daily Value, keep claims within structure/function, nutrient content or authorised health claim routes, meet the declared amount through shelf life, and manufacture to Part 111 specifications.^[1][2][4][5] Check the current eCFR text before finalising any label, because the disclaimer placement rule may change.

For brands & formulators

Food Research Lab helps US supplement brands get vitamin D products right before launch. Our regulatory and scientific research team reviews Supplement Facts panels, % DV calculations, claim wording and substantiation files against current FDA rules, and our nutraceutical product development team links the label claim to the formula, overage and stability plan. We work from Chennai, India, for brands selling in the US.

Vitamin D3 assay, dissolution and stability testing are run or arranged through accredited partner laboratories, and real-time and accelerated studies are explained in our shelf-life testing guide. Send us your draft label and formula through our contact page.

In this series

This guide is part of FRL’s series on developing vitamin D supplements for the US market.

• The VITAL trial explained: what the vitamin D results show and what they allow on a label.
• FDA rules for vitamin D supplements (you are here): Supplement Facts, mcg and IU, % DV, tolerances, claims and cGMP.
• Vitamin D overage in supplements: the hub guide to setting overage so the label claim holds through shelf life.
• Vitamin D3 dissolution testing: inside the lab on how release is tested.
• Vitamin D3 supplement development: a worked example from brief to launch-ready product.
• Nutraceutical product development service: formulation, testing and regulatory support with FRL.

1. U.S. Food and Drug Administration. (2026). 21 CFR 101.36: Nutrition labeling of dietary supplements. Electronic Code of Federal Regulations, current as of 6 November 2026. https://www.ecfr.gov/current/title-21/section-101.36 (cited for mandatory declaration of vitamin D, order, mcg with optional IU, % DV, the compliance sample and exemptions in 101.36(h)).
2. U.S. Food and Drug Administration. (2026). 21 CFR 101.9: Nutrition labeling of food. Electronic Code of Federal Regulations, current as of 6 November 2026. https://www.ecfr.gov/current/title-21/section-101.9 (cited for the vitamin D RDIs (20, 10 and 15 mcg), Class I and Class II compliance and 101.9(g)(5)–(6)).
3. Ross, A. C., Manson, J. E., Abrams, S. A., Aloia, J. F., Brannon, P. M., Clinton, S. K., … Shapses, S. A. (2011). The 2011 report on dietary reference intakes for calcium and vitamin D from the Institute of Medicine: What clinicians need to know. Journal of Clinical Endocrinology & Metabolism, 96(1), 53–58. https://doi.org/10.1210/jc.2010-2704 (cited for the RDAs of 600 IU (ages 1–70) and 800 IU (71 and older)).
4. U.S. Food and Drug Administration. (2026). 21 CFR 101.93: Certain types of statements for dietary supplements. Electronic Code of Federal Regulations, current as of 6 November 2026. https://www.ecfr.gov/current/title-21/section-101.93 (cited for the 30-day notification, disclaimer text, placement and type size, and disease claims).
5. U.S. Food and Drug Administration. (2026). 21 CFR Part 111: Current good manufacturing practice in manufacturing, packaging, labeling, or holding operations for dietary supplements (§§ 111.70, 111.75, 111.83). Electronic Code of Federal Regulations, current as of 6 November 2026. https://www.ecfr.gov/current/title-21/part-111 (cited for specifications, identity testing and reserve sample retention).
6. U.S. Food and Drug Administration. (2016, May 27). Food labeling: Revision of the Nutrition and Supplement Facts Labels (Final rule). Federal Register, 81, 33742. https://www.federalregister.gov/documents/2016/05/27/2016-11867/food-labeling-revision-of-the-nutrition-and-supplement-facts-labels (cited for the effective date, original compliance dates, the move from IU to mcg and the basis of the 20 mcg value).
7. U.S. Food and Drug Administration. (2024). Changes to the Nutrition Facts label. https://www.fda.gov/food/nutrition-food-labeling-and-critical-foods/changes-nutrition-facts-label (cited for the 1 January 2020 and 1 January 2021 compliance dates).
8. U.S. Food and Drug Administration. (2024). Structure/function claims. https://www.fda.gov/food/nutrition-food-labeling-and-critical-foods/structurefunction-claims (cited for no pre-approval, substantiation, the 30-day notification and nutrient deficiency disease claims).
9. U.S. Food and Drug Administration. (2005). Dietary supplement labeling guide. https://www.fda.gov/food/dietary-supplements-guidance-documents-regulatory-information/dietary-supplement-labeling-guide (cited for DSHEA and the 1997 implementing regulations).
10. U.S. Food and Drug Administration. (2026). 21 CFR 190.6: Requirement for premarket notification. Electronic Code of Federal Regulations, current as of 6 November 2026. https://www.ecfr.gov/current/title-21/section-190.6 (cited for the 75-day new dietary ingredient notification).
11. Manson, J. E., Cook, N. R., Lee, I.-M., Christen, W., Bassuk, S. S., Mora, S., … Buring, J. E., for the VITAL Research Group. (2019). Vitamin D supplements and prevention of cancer and cardiovascular disease. New England Journal of Medicine, 380(1), 33–44. https://doi.org/10.1056/NEJMoa1809944 (cited for the VITAL primary results).
12. U.S. Food and Drug Administration. (2018, May 4). Food labeling: Revision of the Nutrition and Supplement Facts Labels …; Extension of compliance dates (Final rule). Federal Register, 83, 19619. https://www.federalregister.gov/documents/2018/05/04/2018-09476/food-labeling-revision-of-the-nutrition-and-supplement-facts-labels-and-serving-sizes-of-foods-that (cited for the extension of compliance dates to 1 January 2020 and 1 January 2021).
13. U.S. Food and Drug Administration. (2026). 21 CFR 101.72: Health claims: calcium, vitamin D, and osteoporosis. Electronic Code of Federal Regulations, current as of 6 November 2026. https://www.ecfr.gov/current/title-21/section-101.72 (cited for the conditions of the calcium and vitamin D health claim).
14. U.S. Food and Drug Administration. (2026). 21 CFR 101.54: Nutrient content claims for “good source,” “high,” “more,” and “high potency”. Electronic Code of Federal Regulations, current as of 6 November 2026. https://www.ecfr.gov/current/title-21/section-101.54 (cited for the 20% DV “high” and 10–19% DV “good source” thresholds).
15. U.S. Food and Drug Administration. (2025, December 11). Letter to the dietary supplement industry regarding the DSHEA disclaimer. https://www.fda.gov/food/information-industry-dietary-supplements/letter-dietary-supplement-industry-dshea-disclaimer (cited for enforcement discretion on the each-panel placement requirement and a likely proposed rule).
16. U.S. Food and Drug Administration. (2026). 21 CFR 101.14: Health claims: general requirements. Electronic Code of Federal Regulations, current as of 6 November 2026. https://www.ecfr.gov/current/title-21/section-101.14 (cited for the definition of a health claim, including implied claims through symbols and vignettes).