Sulforaphane is a chemical found in broccoli sprouts, as well as other cabbage-family vegetables such as broccoli, Brussels sprouts, cabbage, cauliflower, and kale. Some evidence hints that sulforaphane might help prevent cancer.


Sulforaphane is not an essential nutrient. It is found in especially high levels in broccoli sprouts.

Therapeutic Uses

Numerous observational studies have found that a high consumption of vegetables in the cabbage family is associated with a reduced risk of cancer, especially breast, prostate, lung, stomach, colon, and rectal cancer.1 On this basis, scientists have looked for anticancer substances in these foods. Sulforaphane is one such candidate substance ( indole-3-carbinol, I3C, is another). In test-tube and animal studies, sulforaphane exhibits properties that suggest it could indeed help prevent many forms of cancer.2-23,30

However, it is a long way from observational studies to reliable evidence of benefit. Observational studies are notoriously poor guides to treatment, sometimes leading to conclusions that are the reverse of what is ultimately found to be correct.24,25 This is why most evidence is based on double-blind, randomized trials.

That said, there is some promising data to suggest that sulforaphane may help:

  • Fix or reverse genetic defects that allow cancer cells to take hold, grow, spread, or return after treatment27,30
  • Kill cancer cells when combined with chemotherapy for cancer treatment28,30
  • Create a protective environment against the development of neurological diseases, such as stroke, traumatic brain injury, and Parkinson and Alzheimer disease29,30
  • Ease chronic inflammation and reduce its effects on the body30

Keep in mind, these studies encompass both animals and humans. What works in animal studies may not translate into success for humans. Therefore, no specific conclusions can be drawn about sulforaphane use and its benefits. However, newer research has a better understanding of sulforaphane's properties and how it works in the body.

Therapeutic Dosages

The proper daily intake (if there is any) of sulforaphane is not known. Typical recommendations range from 200 to 400 mcg daily.

Safety Issues

No major adverse effects have been reported with sulforaphane supplements, but comprehensive studies have not been performed. Maximum safe doses in young children, pregnant or nursing women, or people with severe liver or kidney disease are not known.

NOTE: Sulforaphane has shown the potential for interacting with numerous medications.26 For this reason, we recommend that people taking any oral or injected medication that is critical to their health or well-being avoid using sulforaphane supplements until more is known.

Interactions You Should Know About

If you are taking any medication that is critical to your health, do not take sulforaphane supplements except under physician supervision.