VITAMINS & SUPPLEMENTS · GUIDE
Supplement Shelf Life and Storage: Heat, Light and Expiry Dates
What the sources say about supplement expiry dates, storage conditions and potency over time, why an old bottle is mainly a strength question, and why storage is also a child-safety question.
Content last updated . This page has not been medically reviewed.
Back to Supplement FormulasKeep supplements out of children's reach
Safe storage is a poisoning-prevention topic first. MedlinePlus (US) says iron overdose is particularly dangerous for children, and that a severe overdose can happen if a child eats adult multivitamins, such as prenatal vitamins. [1] If a child may have swallowed supplements, call Poison Help at 1-800-222-1222 in the US, or 911 if the child is unwell. [1] MedlinePlus notes that symptoms of an iron overdose may go away in a few hours and then return after a day or later, so do not wait for symptoms; have the product name, time swallowed and amount swallowed ready when you call. [1] Outside the US, see poison help by country and read iron overdose and child safety.Do supplements expire?
A date on a bottle is the maker's statement about how long the product is meant to keep its stated contents. We found no source that says an out-of-date vitamin becomes harmful in the way spoiled food can. We also did not find a source that sets a general rule for how much potency is lost after the date. See "What was not found" below.In the US, the manufacturing rule for dietary supplements refers to a "shelf life date (if shelf life dating is used)". [2] That wording is a legal text about keeping reserve samples, not a consumer guide, but it shows that the rule itself does not describe a date as always present. [2] Other countries have their own labeling rules, which we did not read.
What studies found about potency and viability
Do labels already allow for losses?
Promising but limited (one national sampling of adult multivitamins)A US analysis of adult multivitamin/mineral products notes that some ingredients are added above the label claim to compensate for expected losses during shelf life. In measured products, every ingredient except thiamin averaged above its labeled amount. [3]
Probiotics past their date
Promising but limited. Probiotics are living products, so this does not apply to vitamins.Researchers tested 33 expired probiotic products, on average 11 years past expiry. 22 still had viable cells, but total counts were mostly well below the amount the manufacturer recommended. [4]
Probiotic storage temperature
Promising but limitedA 12-month study of commercial multi-strain products found storage temperature was the primary determinant of viability, with ambient storage showing the greatest losses. [5]
Vitamins and minerals after the date, or after heat and humidity
Insufficient evidenceProper evidence not found. We searched PubMed for stability and shelf-life studies of vitamin supplements and found no usable human-relevant review.
Storage conditions
The manufacturing rule says reserve samples are held "under conditions consistent with product labels". [2] In practice, follow the storage directions on your label, because they are written for that product. Storage directions we could confirm in the sources are limited to this principle. We did not find an official source stating specific temperatures for supplements in general, so none are given here.Some formats are more sensitive. Probiotic labels may call for refrigeration, and temperature changed counts in the study above. [5] See probiotic strains and labels.
When to ask a clinician or pharmacist
A pharmacist can help if you are unsure whether an old product is still worth using, especially for a medicine-like supplement, a product for a child, a product used in pregnancy, or something taken for a diagnosed condition. The FDA advises talking to a doctor, pharmacist or other health care professional about supplements, since some can interact with medicines. [6] Do not rely on an old product to treat a suspected deficiency; see vitamin deficiency testing. For product quality questions, see quality testing and certifications.Frequently asked questions
Are expired vitamins dangerous?
In the sources we read, there was no statement that expired vitamins are harmful, and no study of vitamin supplements past their date. The question we could address is potency, which is not the same as safety. Ask a pharmacist if you are unsure.
Do vitamins lose strength after the date?
Proper evidence not found for vitamins and minerals. For probiotics, a study of expired products found counts mostly well below the recommended amount. [4]
Where should supplements be stored?
Follow the directions on the label for that product. The US manufacturing rule refers to holding samples under conditions consistent with product labels. [2] Keep all supplements where children cannot reach them, because iron-containing products can seriously harm a child. [1]
Does a probiotic need to be refrigerated?
Only if its label says so. One 12-month study found storage temperature was the main factor in survival of the live organisms. [5]
Is a supplement without an expiry date a problem?
We did not find a source that treats a missing date as a violation in itself. The US manufacturing rule words dating as optional ("if shelf life dating is used"). [2] A missing date is one reason to ask whether the product meets quality standards; see quality testing and certifications.
More details: evidence, limits and cautions
The details behind this page: cautions, limits of the evidence and where sources disagree. Open any note to read it.
Potency loss versus safety
- Potency is whether the product still contains what the label says. The probiotic studies show living products can fall below their stated counts. [4] For vitamins and minerals we cannot give a rate.
- Safety is whether the old product could harm you. In the sources we read, there was no statement either way for vitamins. Signs such as a changed smell, melted or stuck-together gummies, mold, or damaged seals are worth treating as a reason to replace the product, but that is a common-sense step, not a finding from a study we read.