Orlistat inhibits pancreatic and gastric lipases, preventing fat digestion and absorption. Vitamins A, D, E, and K are all fat-soluble — they require dietary fat for absorption. Orlistat predictably depletes all four simultaneously. This is the drug's mechanism of action working against nutritional status.
Finer et al. (IJCO, 2000) — orlistat reduces serum levels of Vitamins A, D, E, and beta-carotene significantly vs. placebo. FDA label requires monitoring of fat-soluble vitamins and recommends multivitamin supplementation taken at least 2 hours before or after orlistat.
Vitamin D deficiency (bone loss, immune suppression), Vitamin K deficiency (bleeding risk, arterial calcification), Vitamin A deficiency (vision, immune, skin), Vitamin E deficiency (neurological, oxidative stress)
Multivitamin containing A, D, E, K TAKEN 2 HOURS BEFORE OR AFTER ORLISTAT — not with it. Separate timing is critical. Vitamin D3 2,000–4,000 IU + K2 separately. Test fat-soluble vitamin levels at 3 and 6 months.
View on Fullscript: Thorne Vitamin D/K2 Liquid (2 hours apart from orlistat)Discuss with your physician before adjusting supplementation. This is educational content, not medical advice.
Beta-carotene (pro-Vitamin A) is fat-soluble and also blocked by orlistat. Carotenoids have independent antioxidant functions beyond Vitamin A conversion — their depletion increases oxidative stress during a period of significant metabolic change (weight loss).
Cuevas-Ramos et al. — orlistat reduces plasma carotenoids by 20–30%. Given that weight loss itself mobilizes fat-stored carotenoids, the net effect requires monitoring.
Reduced antioxidant protection, immune suppression, skin changes, elevated cancer risk (long-term)
Dietary carotenoids from cooked tomatoes, sweet potato, leafy greens. Supplement mixed carotenoids if dietary intake is poor — again, 2 hours from orlistat.
View on Fullscript: Life Extension Super K (K1 + K2 MK-4 + MK-7)Discuss with your physician before adjusting supplementation. This is educational content, not medical advice.
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