HELSINKI: A new European review has found that having a good vitamin D level may be linked with a lower risk of certain cancers.
Carried out by researchers from the University of Eastern Finland and the Autonomous University of Madrid, the new review includes updated information on the molecular basis of vitamin D and how it may play a role in cancer prevention.
The article, which was published in the journal Seminars in Cancer Biology, says that studies which have looked into the effect of the vitamin on different types of cancers suggest that a ‘good’ vitamin D level, measured as the level of 25-hydroxyvitamin D in the blood, could be particularly beneficial for reducing the risk of colorectal cancer and blood cancers, such as leukemias and lymphomas. Low vitamin D status has also been linked with an increased risk of breast and prostate cancer.
Moreover, low vitamin D levels also appeared to be linked with a higher rate of cancer and a poorer prognosis.
The researchers explain that vitamin D is important both for the functioning of blood cells and adult stem cells in rapidly regenerating tissues, such as colon or skin.
If vitamin D levels are too low then the cells function at a suboptimal level, which may lead to them to turn into uncontrolled growing cancer cells.
However, the team also note that randomised controlled trials which have looked into how vitamin D supplementation might be able to reduce cancer mortality have provided inconsistent results.
The authors say the role of vitamin D might be clearer if studies took into account individual vitamin D responsiveness, which is an individual’s molecular response or sensitivity to vitamin D supplementation.
They add that high vitamin D responsiveness may be linked to a lower risk of cancer. Vitamin D responsiveness varies between individuals, and affects their need for vitamin D supplementation.
For example, 25% of the Finnish population seem to be low responders, say the researchers, and therefore need a higher dose of vitamin D supplementation.
Vitamin D levels can be measured using a 25-hydroxy vitamin D blood test. A level of 20 nanograms/millilitre to 50 ng/mL is considered to be adequate for healthy people. A level less than 12 ng/mL indicates vitamin D deficiency.