E966 — Lactitol
E966 (Lactitol), a sweetener, is rated "watch": fine in moderation. A sugar alcohol used in sugar-free chocolate and low-calorie baked goods. Strong laxative effect at moderate doses; also used medically for constipation.
What is Lactitol?
A sugar alcohol made from lactose, about 30 to 40% as sweet as sugar. Used in sugar-free chocolate and baked goods, and at higher doses as a prescription laxative for chronic constipation.
What does it do to the body?
Hardly absorbed; passes into the colon where it pulls water in and ferments. Even moderate doses (around 10 g) cause noticeable laxative effects in most people. People with IBS react to much smaller amounts.
What regulators say
EFSA and the FDA both approve it as a food additive. EU labels above a threshold must carry the "excessive consumption may produce laxative effects" warning.
Risk rating: Watch
Mixed evidence or a specific concern (gut, allergy, or contested safety data). Not alarming, but worth keeping an eye on rather than eating without limit.