Sodium metabisulphite

Studies in people

• Concern

  Asthma attacks from food additives⁵

  In people with asthma, sodium metabisulphite set off asthma attacks in 3 of 7 tested.

Animal and lab studies only

• Concern

  Liver and kidney stress⁶

  In animal studies, eating sodium metabisulphite raised signs of oxidative stress in rats' livers and kidneys.

• No harm found

  Liver cell gene activity⁷

  In lab studies, sodium metabisulphite did not change apoptosis-related gene expression in HepG2 liver cancer cells.

Allergies and intolerances

These are about people with an allergy, an intolerance or coeliac disease. The signal is about the ingredient itself, and these are about the person eating it, so the signal does not count them.

• Asthma in children³

  In children with asthma, sodium metabisulphite in solution set off reactions, but the capsule form did not.

• Asthma reactions to food additives⁴

  In people with asthma, sodium metabisulphite triggered reactions in only a small number tested.

The signal at the top counts the findings in people and in animal and lab studies. A concern in studies of people outranks animal and lab studies, and “No concerns” needs at least one finding in people. When most findings in people point one way, the page leans that way (“Mostly”), and every finding is still shown. Findings whose study type is not stated are shown but not counted. This page is a reference, not medical advice. It describes what regulators and published research say. Talk to a doctor or dietitian about your own diet.

Expert panels that weigh all the research. Shown for context: the signal at the top does not count them. IARC rates whether something can cause cancer at all, not how likely it is at the amounts in food.

• UN and WHO food additive experts (JECFA), 1998

  Acceptable daily intake: up to 0.7 mg per kg of body weight.

• WHO cancer agency (IARC), 1991

  For metabisulfites: not enough evidence to say whether it causes cancer in people (Group 3).