According to a very large study which has been recently published in the British Medical Journal, a high level of vitamin D protects against cancer.
Vitamin D is a quasi-hormone synthesized from a precursor that is found in different foods but which has to be activated by the ultraviolet radiations of the sun. Thus, a diet lacking in Vitamin D precursors or low exposure to the sun may lead to Vitamin D deficiency which may cause serious health problems.
Vitamin D protects against cancer
This new study has shown that vitamin D, and especially its activated form, 25-hydroxyvitamin D, could have a blocking effect on the actions of the cancer cells across multiple signaling pathways of the cells involved in the cell death process (scientifically known as apoptosis), the creation of blood vessels (angiogenesis), and inflammation, all of which have been reported in colon and breast cancer forms.
The protective effects of vitamin D against cancer are much more controversial in clinical studies and the results of epidemiological studies are contradictory.
A large study has been conducted
This is the largest study measuring the 25-hydroxyvitamin D levels in the blood of men and women with cancer.
It involved more than 30,000 Japanese who were followed for 16 years. Its results took into account all the factors that could have disrupted the validity of the examinations, such as age, sex, weight, alcohol consumption, smoking, eating habits, and so on.
Lower levels of Vitamin D have been noticed in the majority of cancers types except lung and prostate cancers but have also been observed especially in the cases with liver cancer, as the liver is the organ that produces 25-hydroxyvitamin D.
Compared with the previous studies, this research collected the greatest number of vitamin D measurements and showed that vitamin D protects against cancer but also that, when taken in excess the vitamin D become useless.