{"ok":true,"entry":{"slug":"chitosan","kind":"supplement","name":"chitosan","aliases":["fat binder","shellfish chitin"],"brands_sg":["NOW Foods","Natural Balance","KAL","Nutricology","Absolute Nutrition"],"class":"fiber-like polysaccharide","tags":["general"],"use_for":"binds some dietary fat; ods: minimal effect on body weight","use_after":"trials dosed it with the largest meals","use_duration":"trials ran 4 weeks to 6 months","take_with":"meals · one trial paired 3 g with 2 g ascorbic acid","pros":["cochrane pooled 13 trials: 1.7 kg below placebo","0.24–15 g/day for up to 6 months: few safety flags","reported side effects are minor and gut-related"],"cons":["ods: minimal effect, probably clinically insignificant","shellfish-derived — a shellfish allergy is a risk","flatulence, bloating, constipation, heartburn"],"dose_note":"trials used about 2–3 g a day, split across the largest meals, for 4 weeks to 6 months; ods reports few safety concerns across 0.24–15 g a day for up to 6 months, and in the fat-excretion study at 2.5 g a day the trapped fat would amount to a loss of only about 1 lb of body fat over roughly 7 months","dosage":{"ul":null,"unit":"g","fda_dv":null,"rda_ai":null,"ul_status":"none_established","population":"general adult","hsa_max_daily":null},"ul_status":"none_established","sg_class":null,"cautions":["shellfish allergy — chitosan is prepared from the exoskeletons of crustaceans, so an allergic reaction is possible","expecting a weight result — the pooled high-quality trials show effects ods calls probably clinically insignificant","hsa: chitosan is not listed in annex a or annex b of the oct 2025 prohibited/restricted guideline, which hsa itself says is not exhaustive — no sg maximum or label warning applies to it"],"clashes":[],"sources":[{"id":"ods_chitosan_table","url":"https://web.archive.org/web/20260826105104/https://ods.od.nih.gov/factsheets/WeightLoss-HealthProfessional/","label":"NIH ODS — Dietary Supplements for Weight Loss (Health Professional), summary table row for chitosan (read via the archive.org capture; ods.od.nih.gov returns 403 to a direct fetch)","quote":"Chitosan … Binds dietary fat in the digestive tract … Minimal effect on body weight … Few safety concerns reported for 0.24–15 g/day for up to 6 months; could cause allergic reactions","accessed":"2026-08-27"},{"id":"ods_chitosan_cochrane","url":"https://web.archive.org/web/20260826105104/https://ods.od.nih.gov/factsheets/WeightLoss-HealthProfessional/","label":"NIH ODS — Dietary Supplements for Weight Loss (Health Professional), chitosan efficacy, Cochrane Review (read via the archive.org capture; ods.od.nih.gov returns 403 to a direct fetch)","quote":"a Cochrane Review that included 13 trials … found that chitosan, when taken for 4 weeks to 6 months, reduced body weight by a mean of 1.7 kg compared with placebo","accessed":"2026-08-27"},{"id":"ods_chitosan_dose","url":"https://web.archive.org/web/20260826105104/https://ods.od.nih.gov/factsheets/WeightLoss-HealthProfessional/","label":"NIH ODS — Dietary Supplements for Weight Loss (Health Professional), chitosan efficacy, 8-week trial dosing (read via the archive.org capture; ods.od.nih.gov returns 403 to a direct fetch)","quote":"One clinical trial randomly assigned 59 women with overweight or obesity (BMI 27–40) to receive either chitosan (3 g/day divided between the two largest meals) or placebo for 8 weeks","accessed":"2026-08-27"},{"id":"ods_chitosan_ascorbic","url":"https://web.archive.org/web/20260826105104/https://ods.od.nih.gov/factsheets/WeightLoss-HealthProfessional/","label":"NIH ODS — Dietary Supplements for Weight Loss (Health Professional), chitosan efficacy, chitosan plus ascorbic acid (read via the archive.org capture; ods.od.nih.gov returns 403 to a direct fetch)","quote":"The effect of chitosan (3 g/day) with or without ascorbic acid (2 g/day) was evaluated in an 8-week study in women age 20–30 who were overweight","accessed":"2026-08-27"},{"id":"ods_chitosan_fatexcretion","url":"https://web.archive.org/web/20260826105104/https://ods.od.nih.gov/factsheets/WeightLoss-HealthProfessional/","label":"NIH ODS — Dietary Supplements for Weight Loss (Health Professional), chitosan efficacy, fecal fat excretion study (read via the archive.org capture; ods.od.nih.gov returns 403 to a direct fetch)","quote":"the amount of fat that the chitosan trapped would result in a loss of only 1 lb body fat over about 7 months","accessed":"2026-08-27"},{"id":"ods_chitosan_safety","url":"https://web.archive.org/web/20260826105104/https://ods.od.nih.gov/factsheets/WeightLoss-HealthProfessional/","label":"NIH ODS — Dietary Supplements for Weight Loss (Health Professional), chitosan safety (read via the archive.org capture; ods.od.nih.gov returns 403 to a direct fetch)","quote":"The adverse effects of chitosan are minor and primarily involve the gastrointestinal tract. They include flatulence, bloating, mild nausea, constipation, indigestion, and heartburn … people who are allergic to shellfish could theoretically be allergic to chitosan","accessed":"2026-08-27"},{"id":"hsa_annex_notlisted","url":"https://file.go.gov.sg/hsa-chp-prohibited-restricted-ing-guidelines.pdf","label":"HSA — Guidelines on Prohibited and Restricted Ingredients in Health Supplements and Traditional Medicines, GL-CHPB-1-012 Rev. No. 001 (Oct 2025) — Annex A (118 substances, prohibited/restricted) and Annex B (4 substances: caffeine, Camellia sinensis extract, Hypericum perforatum, L-tryptophan) both read in full: chitosan is NOT LISTED in Annex A or Annex B","quote":"The objective of this guideline is to highlight the substances of concern when used in HS and TM and is not meant to be an exhaustive list.","accessed":"2026-08-27"},{"id":"iherb_sg","url":"https://sg.iherb.com/c/chitosan","label":"iHerb Singapore — Chitosan category (default order, \"1 - 8 of 8 results\")","quote":"NOW Foods, Chitosan plus Chromium … NOW Foods, Chitosan, 240 Veg Capsules … Natural Balance, Super Chitosan 3000 … KAL, Chitosan, 750 mg … Nutricology, MicroChitosan™ … Absolute Nutrition, FBlock™, Fat Absorber","accessed":"2026-08-27"}],"brand_certs":null,"updated_at":"2026-08-29T16:16:14.713299+08:00"},"disclaimer":"kozen-x is not a medical device and does not give medical advice. it lists what published sources have written down. absence of a record is not the same as safe."}