Don’t take vitamin B3 to prevent skin cancer – stick with shade

If you saw the news this morning, you might have spotted a story suggesting that vitamin B3 tablets might be able to prevent skin cancer.

On the one hand, technically, this indeed a true reflection of what research has found.

On the other,  it’s a more complex picture than the headline implies – as is often the case.

Let’s be completely clear: the research doesn’t show that taking over-the-counter vitamin B3 supplements can protect you in the sun. Far from it. And our advice on enjoying the sun safely remains unchanged.

So, why the confusing headlines?

What was the study?

The story came from research due to be presented at the annual American Society of Clinical Oncology (ASCO) conference later this month by researchers in Australia (you can read the research summary here).

The team were looking at ways to help people who had been diagnosed with a less-serious, but relatively common, form of skin cancer called non-melanoma skin cancer, and who were at high risk of the disease coming back.

All of the 390 patients on the trial had had at least two diagnoses of the disease within the last five years, and had been diagnosed around eight times on average.

The team’s previous research had previously hinted that a particular form of vitamin B, called nicotinamide, might slow down the rate at which the disease came back.

So they set out to test this idea in a clinical trial.

The researchers gave nicotinamide tablets to half of the patients, while the other half took a placebo pill.

After a year, fewer patients who had taken daily nicotinamide had a recurrence of their skin cancer – a really promising result.

But what does this mean for the rest of us?

Wider applicability?

Here are a series of facts that, together, should explain why this study doesn’t mean anything for those of us about to pack for the summer holidays:

• The study didn’t look at melanoma, the most serious form of skin cancer which, like non-melanoma skin cancers, is also linked to overexposure to UV from the sun and sunbeds.
• People on the study took nicotinamide every day for a year.
• It didn’t completely stop the disease coming back, just slowed the rate at which it did so.
• It didn’t look at ‘healthy’ people – it looked at older Australians who already had so much skin damage they were at risk of multiple skin cancers.
• Nicotinamide – the chemical used in the study – is slightly different from as the ‘common-or-garden’ vitamin B3 supplements, which contain a version of the nutrient called niacin.

All in all – despite the fact that it suggests a cheap and readily available way for doctors to help people at risk of multiple recurring skin cancers – this study says nothing that changes our existing sun advice: when the sun is strong, spend time in the shade, cover up with clothing, and use sunscreen that’s at least SPF15 & 4 stars.

And, just in case it needs repeating – it certainly doesn’t provide evidence that you can take a vitamin pill to protect against skin cancer.

Henry