Quick answer
Ask your pharmacist or doctor before combining. NIH says orlistat can reduce how much vitamin D the body absorbs from food and supplements. The label advises a daily multivitamin with vitamins A, D, E and K at a separate time, and reports low vitamin D in 12.0% of unsupplemented adults on orlistat against 6.6% on placebo.1,2
Key facts
- NIH says orlistat can reduce the vitamin D absorbed from food and supplements, and its sheet for professionals adds that this happens together with a reduced-fat diet and leads to lower 25(OH)D levels.1,3
- The label says orlistat reduces absorption of some fat-soluble vitamins and advises a daily multivitamin containing them, taken at a separate time.2
- In the label's trials, low vitamin D values on two or more consecutive visits occurred in 12.0% of adults on orlistat who took no vitamins, against 6.6% on placebo.2
- The label's interaction section says the effect of orlistat on absorption of supplemental vitamin D is not known, although it reduced absorption of beta-carotene and vitamin E supplements in a study.2
- MedlinePlus says orlistat prevents some of the fat in food from being absorbed and asks people to take a daily multivitamin containing vitamins A, D, E and K.4
Ask your pharmacist how far apart to take them
Orlistat, a weight-loss medicine, reduces the absorption of fat-soluble vitamins, including vitamin D. Its label advises a daily multivitamin with vitamins A, D, E and K taken at a separate time from orlistat, and in its trials low vitamin D levels were more common on orlistat than on placebo.1,2,4
On the medicine's label
What do NIH, the label and MedlinePlus say about vitamin D and orlistat?
NIH's consumer sheet on vitamin D calls orlistat a weight-loss drug and says it can reduce the amount of vitamin D the body absorbs from food and supplements. The sheet for health professionals says orlistat, together with a reduced-fat diet, can reduce vitamin D absorption and lead to lower 25(OH)D levels, the blood measure of vitamin D.1,3
The orlistat label says the medicine has been shown to reduce the absorption of some fat-soluble vitamins and beta-carotene, so patients should be counseled to take a multivitamin containing fat-soluble vitamins. MedlinePlus says the same and asks people to read the product label to find a multivitamin with vitamins A, D, E and K and beta-carotene.2,4
Why would orlistat lower vitamin D?
MedlinePlus describes orlistat as a lipase inhibitor that stops some of the fat in the food you eat from being absorbed, which passes out in the stool. Vitamin D travels with dietary fat, so less fat absorbed means less vitamin D absorbed.1,4
Vitamin D is fat soluble, so it is best absorbed with a meal or snack that includes some fat. Some is absorbed even without fat.1,3
Do the sources agree on whether orlistat lowers absorption of vitamin D supplements?
| Source | What it says | What kind of statement it is |
|---|---|---|
| NIH consumer sheet | Orlistat can reduce the amount of vitamin D absorbed from food and supplements. | A plain statement. |
| NIH sheet for professionals | Orlistat with a reduced-fat diet can reduce absorption of vitamin D from food and supplements, leading to lower 25(OH)D levels. | A statement that cites studies. |
| Orlistat label, trial results | In adults with normal starting values who took no vitamins, low vitamin D values on two or more consecutive visits were 12.0% on orlistat and 6.6% on placebo over the first two years. | Measured blood values, not absorption. |
| Orlistat label, interaction section | A study showed reduced absorption of a beta-carotene supplement and inhibited absorption of a vitamin E supplement. The effect on supplemental vitamin D, vitamin A and food vitamin K is not known at this time. | Says what has and has not been tested. |
| MedlinePlus | Orlistat blocks absorption of some fat-soluble vitamins and beta carotene. | A general statement. |
So the sources do not say exactly the same thing. NIH states the effect on vitamin D plainly. The label shows low vitamin D values more often on orlistat in its trials but says the effect on vitamin D supplements has not been established. The label and MedlinePlus both point to the same step: a multivitamin with fat-soluble vitamins.1,2,4
What vitamins should I take with orlistat?
The label and MedlinePlus both describe a daily multivitamin that contains vitamins A, D, E and K and beta-carotene, taken at a separate time from orlistat. The label and MedlinePlus each give a specific gap, which this page does not repeat because it depends on your own meals and doses. MedlinePlus adds that you can ask your doctor or pharmacist any questions about taking a multivitamin with orlistat.2,4
Neither gives an amount of vitamin D for people taking orlistat. NIH says multivitamins have no standard formula, with each maker choosing which nutrients go in and how much, so the vitamin D in two multivitamins can differ.5
What if vitamin D is already low?
The label notes that vitamin D and beta-carotene levels may be low in people with obesity compared with people without it, which is one reason the starting level matters. Neither the label nor NIH says what to do about orlistat for someone whose vitamin D is already low, or what amount of vitamin D to use.2
NIH says vitamin D status is measured with a blood test for 25-hydroxyvitamin D. A clinician can read that result alongside your medicines, which is something this page cannot do.1
What to ask your pharmacist about vitamin D and orlistat
- Which multivitamin has vitamins A, D, E and K, and how does it fit around my orlistat doses?
- I already take vitamin D on its own. How does it fit with the multivitamin?
- Should my vitamin D level be checked while I take orlistat?
- What should I do on a day when I skip a meal or a dose of orlistat?
Questions people ask
Can you take vitamin D with orlistat?
Ask your pharmacist or doctor first. NIH says orlistat can reduce vitamin D absorbed from food and supplements, and the label advises a daily multivitamin with vitamins A, D, E and K at a separate time from orlistat.1,2
What vitamins should I take with orlistat?
The label and MedlinePlus both describe a daily multivitamin containing vitamins A, D, E and K and beta-carotene. Ask your pharmacist which product and when.2,4
What vitamins to take with orlistat if I already take vitamin D?
The sources do not say how a separate vitamin D supplement fits with the multivitamin. Tell your pharmacist about both so the total can be reviewed.
Is vitamin D deficiency a risk with orlistat?
In the label's trials, low vitamin D values were more common on orlistat than on placebo among adults who took no vitamins. The label's interaction section says the effect on vitamin D supplements is not known.2
Can you take orlistat with vitamin D deficiency?
The sources do not address starting orlistat when vitamin D is already low. Ask your prescriber, who can order a 25-hydroxyvitamin D blood test and review your medicines.1
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Sources
- Office of Dietary Supplements, National Institutes of Health. Vitamin D: Fact Sheet for Consumers. Updated November 8, 2022. Opened 2026-10-07.
- Orlistat capsules: prescribing information (H2-Pharma). DailyMed, U.S. National Library of Medicine. Published January 12, 2026. Opened 2026-10-07.
- National Institutes of Health, Office of Dietary Supplements. Vitamin D: Fact Sheet for Health Professionals. Updated June 27, 2025. Opened 2026-10-07.
- Orlistat. MedlinePlus Drug Information, U.S. National Library of Medicine. Last revised September 15, 2026. Opened 2026-10-07.
- National Institutes of Health, Office of Dietary Supplements. Multivitamin/mineral Supplements: Fact Sheet for Health Professionals. Updated July 17, 2024. Opened 2026-10-01.
This page is information, not medical advice. Talk to your doctor or pharmacist about your own situation.