Research review
Probiotics and vitamin D: what the research does and doesn't show
One named strain, L. reuteri NCIMB 30242, raised blood vitamin D by 17.1 nmol/L more than placebo in a post hoc analysis of 127 adults over 9 weeks, with no vitamin D given. No trial we found tested taking probiotics and vitamin D together for each other's sake.
The evidence doesn't support a general claim that probiotics raise vitamin D. One named strain, L. reuteri NCIMB 30242, raised blood vitamin D by 17.1 nmol/L more than placebo in a post hoc analysis of 127 adults over 9 weeks, with no vitamin D given. Taking both together hasn't been tested for that.
What the evidence doesn't support
It doesn't support the idea that probiotics in general raise vitamin D levels, that probiotics improve absorption of a vitamin D supplement, or that taking the two together does more than either alone. The one trial result we found is for a single strain, in a secondary analysis, with no vitamin D supplement given. We found no trial built to test a probiotic and vitamin D against each other. The trials that give both together, as far as we found, test them for specific conditions and can't separate what each one contributed. A review of 249 trials across probiotic uses found that effects are strain-specific and purpose-specific and that many products have no trial of their own.
What the trial found
A double-blind, placebo-controlled trial in 127 otherwise healthy adults with raised LDL cholesterol, run in Prague, gave L. reuteri NCIMB 30242 capsules or placebo for 9 weeks. Its primary outcome was LDL cholesterol; fat-soluble vitamins were analysed afterwards, which makes the vitamin D finding a post hoc analysis, a result to test again rather than one the trial was designed to prove. Serum 25-hydroxyvitamin D rose by 14.9 nmol/L (25.5%) in the probiotic group, a significant 17.1 nmol/L (22.4%) difference from placebo (P = 0.003). Vitamin A, vitamin E and beta-carotene did not differ, and dietary intake did not differ between groups. The authors called it, to their knowledge, the first report of circulating 25-hydroxyvitamin D rising in response to an oral probiotic. The dose isn't given in the abstract.
| Strain | People | Length | Result versus placebo | Caveats |
|---|---|---|---|---|
| L. reuteri NCIMB 30242 | 127 adults with raised LDL | 9 weeks | 25-hydroxyvitamin D up 17.1 nmol/L | Post hoc; single strain; no vitamin D given |
Whether that rise would also happen with other strains, in people with low vitamin D, or alongside a vitamin D supplement hasn't been shown by anything we found.
Probiotic effects are strain-specific, so a result for one named strain is not a result for "probiotics" in general, and a product that lists species without strain codes can't borrow it. See what the research shows across probiotics and how to choose a probiotic.
Questions people ask
Do probiotics increase vitamin D?
One strain did in one post hoc analysis of 127 adults. That is a lead, not a finding that probiotics raise vitamin D, and it says nothing about other strains.
Can you take probiotics and vitamin D together?
We found no study showing a problem or a benefit from taking them together. Follow the directions on each label. See probiotics interactions and best time to take probiotics.
Does vitamin D help probiotics work?
We found no trial testing this.
When to talk to a doctor
If you take prescription medication, are pregnant or nursing, have a weakened immune system or a medical condition, or are under 18, ask a doctor or pharmacist before adding any supplement (see who should not take probiotics). Nothing here is a reason to change or skip anything a doctor has recommended.
Sources
- Oral supplementation with probiotic L. reuteri NCIMB 30242 increases mean circulating 25-hydroxyvitamin D: a post hoc analysis of a randomized controlled trial In 127 adults, one named L. reuteri strain raised blood vitamin D levels over 9 weeks compared with placebo, in a post hoc analysis with no vitamin D supplement given.
- Choosing an appropriate probiotic product for your patient: An evidence-based practical guide A review of 249 trials found probiotic effects depend on the exact strain and the purpose, and many products have no trial of their own.
*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.