L-cysteine

Studies in people

• Benefit

  Hangover symptoms²

  In a study of men, L-cysteine seemed to prevent or ease hangover, nausea, headache, stress and anxiety.

Animal and lab studies only

• Benefit

  Blood sugar control³

  In animal studies, L-cysteine improved how the body handles sugar, but scientists do not yet know whether it helps people with diabetes.

• Benefit

  Vitamin D levels⁴

  In lab and animal studies, l-cysteine helped raise glutathione, which may help the body turn vitamin D into its active form.

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 two findings in people. 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.