Vitamin D protects against colon cancer
January 26, 2010
A huge European study now confirms that vitamin D may lower the risk of colon cancer by 40%.
The Danish Vitality Council has in several previous newsletters refered to scientific studies showing that vitamin D may lower the risk of cancer, and we have even been urged by journalists to withdraw those statements. Fortunately we have not complied.
A few days ago British Medical Journal published the largest study ever of the link between diet and health, known as the EPIC study, and this is just one of many results, we will see in the near future from this huge study.
More than half a million mostly healthy people from ten European countries have been closely studied and followed over 10 years by researchers from across Europe.
Participants completed detailed dietary questionnaires, and they have been checked with blood tests to identify their nutritional status.
At the time of analysis 1,250 cases of colon cancer had occurred and after comparison with a healthy control group researchers found that those who were low in vitamin D in their blood had significantly higher risk for this type of cancer.
Unlike many other studies this is characterized by being a prospective study. Thus looking-forward from the start time, and based on a group of healthy people. The study also distinguishes itself by involving so many different countries, cultures and – not least – food cultures.
Vitamin D, we primarily get from the sun, and a little bit from the diet. Danes are not the most tenacious fish eaters and much of the fish we eat is farmed and therefore does not include the fatty acids and other substances, we think they contain.
So we’re back at sunlight as the main natural source of vitamin D.
However, some of our ancestors for inscrutable reasons have found reason to settle north of the Alps, and it leads to midday sun high enough in the sky to make enough vitamin D in the skin for only 3-4 months a year (providing we have enough cholesterol).
So we must therefore tend to sunbathing when the Sun is at its highest point, ie the middle of the day, without sunblock, and therefore only half an hour, so we do not risk burning.
If it gets too complicated, you can also just grab a vitamin D capsule as a supplement. It is perhaps a little easier, and it can be done the whole year.
The dosage is somewhat controversial and should ideally be measured in a blood sample, but most serious scientists recommend between 2,000 and 4,000 IU, equivalent to 50-100 micrograms daily.
It will take a long time before we again will see such a thorough, multi-national study including so many people over such a long period.
So it is not just any study. It has high validity and ought to push the critically low RDA-value we have today.
By: Vitality Council
Litterature:
Jenab, M. et al (2010). Association between pre-diagnostic circulating vitamin D concentration and risk of colorectal cancer in European populations: A nested case-control study BMJ, 340 (jan21 3)
Can be downloaded directly at: www.bmj.com/cgi/content/abstract/340/jan21_3/b5500