Orlistat (Weight Loss / Fat Blocker)
Common brand names: Xenical (Rx), Alli (OTC)
Two nutrients listed against this medication. The most severe is marked critical.
At a glance
All two are marked well documented.
At a glance
- Fat-Soluble Vitamins (A, D, E, K)Critical · Well documented
- Beta-CaroteneModerate · Well documented
Color shows how serious each listed effect is. The label beside it shows how strong the evidence is. The cards below explain each one and show its evidence.
Nutrients it can lower
Mechanism, Orlistat inhibits pancreatic and gastric lipases, preventing fat-soluble vitamin absorption. Vitamins A, D, E, and K all require dietary fat. This is the drug's mechanism of action working against nutritional status.
Common signs, Vitamin D deficiency, Vitamin K deficiency (bleeding risk), Vitamin A deficiency, Vitamin E deficiency (neurological)
Finer et al. (Int J Obes, 2000; PMID PubMed ID: the permanent number the US National Library of Medicine gives a published paper. Each one links to that paper's record on PubMed. 10757623): 1-year orlistat RCT Randomized controlled trial: people are assigned to the treatment or a comparison by chance, so the groups differ only in what they received. It is the design that can show cause and effect.: significant falls in vitamin E and beta-carotene; fat-soluble vitamin (A, D, E) supplements were required in some patients.
A multivitamin containing A, D, E and K is separated from orlistat by 2 hours, before or after, because the drug blocks fat absorption. The vitamin D3 2,000–4,000 IU figure and the 3 and 6 month testing interval are common practice, not from a trial cited on this row.
Mechanism, Beta-carotene is fat-soluble and also blocked by orlistat. Carotenoids have independent antioxidant functions beyond Vitamin A conversion.
Common signs, Reduced antioxidant protection, immune suppression, skin changes
Finer et al. (Int J Obes, 2000; PMID 10757623): in a 1-year RCT, orlistat significantly reduced plasma beta-carotene and vitamin E versus placebo An inactive substitute made to look like the real treatment, so participants cannot tell which one they received. (P<0.001).
Dietary carotenoids (cooked tomatoes, sweet potato, leafy greens) are emphasized; where dietary intake is poor, mixed carotenoids were used, separated from orlistat by 2 hours.
For your next appointment
It prints or saves as a single page. Whether to add a supplement for a nutrient this medication may lower is a decision for your prescriber.
Disclosure
These statements have not been evaluated by the Food and Drug Administration. Any grade on this page describes the strength of published human trial evidence in the populations studied. It is not a recommendation for any individual and is not medical advice. Starting, stopping or changing any supplement or medication is a decision for your physician.
Grades move when new trials publish. A free monthly email lists every grade EBL moved, with the reason and the trial behind it: the sign-up is on the Evidence Log →