Condition
Skin Cancer
Skin cancer starts when skin cells, often damaged by sunlight, grow out of control; the main types are basal cell, squamous cell, and melanoma. The evidence is strongest for nicotinamide, a form of vitamin B3, in people at high risk of new skin cancers, though studies found no clear difference for melanoma. Large beta-carotene trials found no reduction in non-melanoma risk, and evidence for other supplements is limited.
- Supplements studied
- 2
- Graded outcomes
- 3
- Trials
- 1
- People studied
- 1,234
Evidence by supplement
- Strong
- Moderate
- Limited
- Very limited
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Non-Melanoma Skin Cancer Risk No significant reduction in risk compared to placebo (large RCTs) | NoneNo effect | 30,000 people | ||||
| Melanoma Risk No effect on melanoma risk (meta-analysis of RCTs: RR 0.98) | NoneNo effect | 15,000 people |
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Melanoma Risk No effect | NoneNo effect | 416 people | ||||
| Non-Melanoma Skin Cancer Risk | Changes; see studies | 2 studies | 552 people | |||
Studies that measured non-melanoma skin cancer risk | ||||||
Key findings
- Non-Melanoma Skin Cancer Risk
- Melanoma Risk
Safety notes in the studies
- No significant reduction in risk compared to placebo (large RCTs)
- No effect on melanoma risk (meta-analysis of RCTs: RR 0.98)
The Skin Cancer Supportive Care protocol
2 primary supplements · 7 supporting supplements
- Vitamin D2,000–4,000 IU daily (monitor levels)
- Nicotinamide (Vitamin B3)500 mg twice daily (for prevention in high-risk individuals)
Studies cited
1 study from PubMed