Vitamin D inhibits cancer
June 26, 2007
An overlooked but very sensational study suggests that vitamin D could inhibit almost 80% of all cancer cases. We just need much more than we normally get (1).
One out of every three people in Britain die of cancer and a world without this feared disease seems utopian. But if an American study is correct, we can approach this unattainable goal with a historic leap forward. We just need more, much more, vitamin D, and maybe also more calcium. According to the study, a combination of calcium and vitamin D can reduce the risk of cancer by about 60%. Additionally, it seems that if cancer is avoided during the first year of taking supplements, then the risk of cancer the following year is reduced by nearly 80%! It is hard to expect more.
It is strange that such sensational news has received almost no official consideration. Especially because it comes from a highly trustworthy double blind, randomised trail published by highly respected researchers.
The participants in the study were 1,180 women with an average age of 67. They were from Nebraska, which is just as far south as southern Italy and receives a lot of sun. Not surprisingly the women had on average good blood levels of vitamin D before the study.
In the study 446 of the women received an advantageous daily supplement of as much as 1,100 units (27.5 micrograms) vitamin D. This is at least five times more than the contents of a normal vitamin pill and about three times the recommended dosage for people over age 60. They also received 1.5 gr. calcium (as carbonate or citrate), which is about the amount of calcium in a litre of milk.
Another 445 women received only calcium and 288 received placebo. Neither the women nor the researchers knew who got what. The study lasted for four years while it was noted who and how many got cancer.
We now have the results. The group which received the vitamin D and calcium was subject to many fewer cases of cancer than the group which received placebo. The difference was not coincidence! It was statistically extremely solid. The biggest difference (77% lower risk) was shown during the last three years of the study. The researchers surmised that this was because some of those who got cancer in the beginning of the study already had undetected cancer before the study started.
It could be true
The women who just received calcium also had a lower risk of cancer (40%). This finding was not completely certain statistically. The cancer risk for these women did not, as in them who received both vitamin D and calcium, become more reduced after the first year. It is therefore uncertain if this effect is actual or just the result of coincidence.
On the other hand, at least two further arguments indicate that vitamin D actually works. The first is that the women who had the poorest vitamin D status before the study, were those helped the most, their risk was the most reduced. The vitamin D status of the participants during the study also played a role, the lower the status, despite the supplements, the larger the cancer risk. The second argument that vitamin D has this effect is that the risk was directly link to the amount of vitamin D used.
Can it really be true that something as cheap as vitamin D can be so beneficial? We know that the vitamin regulates at least 200 genes, many of which control the cells’ growth and degree of specialisation. Animal studies have shown that vitamin D deficiency promotes cancer growth. For more than 60 years it has been known that cancer is less common in countries where the sun is high in the heavens leading to the production of more vitamin D in the skin. It has also be proven time and time again that low vitamin D status and high cancer risk in people go hand in hand (2,3).
The only thing that has been missing is a proper study with sufficient supplements so that cause and effect could be analysed. We now have just that study!
The women in Nebraska had a typical vitamin D status (25-hydroxy-vitamin-D3 in the serum) of 71 nanomolsl/L before the study. This is a very acceptable value. But the supplement increased this value to an average of 96. This is normally regarded as too high.
Vitamin D status is measured with a blood test! It is most important during the winter, when it is the lowest. According to the Nebraska study, this level should be no less than 100.
By: Vitality Council
1) Lappe J M et al. Vitamin D and calcium supplementation reduces cancer risk: Results of a randomized trial. Am J Clin Nutr 2007;85:1586-91.
2) Feskanich D et al. Plasma vitamin D metabolites and risk of colorectal cancer in women. Cancer Epidemiol Biomarkers Prev 2004;13:1501-8
3) Ahonen M H et al. Prostate cancer risk and prediagnostic serum 25-hydroxyvitamin D levels (Finland). Cancer Causes Control 2000;11:847-52