The Daily Express today has a piece titled “The 20p ‘sunshine pill’ helps cancer patients live longer“. That’s a bold, unambiguous claim. Taking this pill will improve cancer survival rates, right?
A British oncologist will next week tell a conference that many of his skin cancer patients have unusually low levels of vitamin D.
He now gives them supplements and says they often survive for longer than expected.
Although he has not yet done a clinical trial to back up his theory, he believes that vitamin D pills at just 20p a day could eventually prove as effective as cancer treatments that cost thousands of pounds per patient.
Oh. So it might help cancer patients live longer one day, according to a doctor who hasn’t tested his theory yet.
There is some reasonably good evidence, summarised at Wikipedia, that low levels of vitamin D (a chemical produced when the skin is exposed to sunlight which controls bone growth and the life cycle of cells) are linked to an increased risk of certain types of cancer and faster cancer growth, but the cause and effect aren’t clear – are low vitamin D levels causing cancer, or is cancer causing low vitamin D levels? – and, as Cancer Research UK says:
We strongly advise cancer patients to talk to their doctor if they are concerned, before considering taking supplements – especially since there’s evidence that some vitamin supplements can have unintended consequences. Moreover, vitamin D from supplements doesn’t appear to be regulated in the body as tightly as vitamin D from the sun – and there’s still a lot of uncertainty over what the ‘best’ dose is.
And we certainly don’t recommend that patients go overboard on the beach or sunbeds to top up their vitamin D. We know that we all need a bit of sunshine in our lives. But we also know that excessive UV exposure (from the sun or sunbeds) and sunburn are major risk factors for melanoma.
That’s some very good advice, which makes it all the more galling that the Daily Express is encouraging cancer patients to start taking vitamin D pills without visiting their doctor.