Studies Is Vitamin D Important Protection Against Cancer?

Does it make sense to take dietary supplements with vitamin D.?

The benefits of vitamin D supplements are controversial. Japanese researchers have now found that vitamin D appears to protect the body from cancer. This raises the question of whether dietary supplements with vitamin D in the sense of cancer prevention make sense.

Researchers at the Center for Public Health Sciences at the National Cancer Center in Tokyo found that vitamin D may protect against cancer. The physicians published the results of their study in the English-language journal British Medical Journal (BMJ).

Vitamin D is abundant, e.g. in fatty fish (salmon, herring etc.), eggs, butter and cheese. (Image: bit24 / fotolia.com)

How does vitamin D get into the body??

Vitamin D plays an important role in the body, for example, the vitamin protects bones and muscles and prevents diseases such as rickets. Vitamin D is produced when the human skin is exposed to sunlight. It can also be taken with certain foods, such as eggs and oily fish. It is also possible to take vitamin D in dietary supplements.

Vitamin D protects against liver cancer

The Japanese researchers say that higher levels of the vitamin are associated with a lower risk of cancer, especially in liver cancer. Vitamin D also has a weak effect on several types of cancer, says study author Taiki Yamaji from the National Cancer Center in Tokyo.

Physicians analyzed blood samples from more than 30,000 subjects

This was not the first study suggesting that people with a low vitamin D level might be at an increased risk for a range of cancers. However, the results are not clear, as some studies have found no such effect and suggest other protective effects against certain types of cancer. The current study addressed this problem. The team studied concentrations of the biologically active form of vitamin D in blood samples from more than 30,000 middle-aged people in health centers across Japan during the early 1990s. Participants in the study were medically monitored over a median of 16 years. Researchers based their analysis on data from a total of 3,301 participants who developed cancer after enrolling for the study. In addition, a further 4,044 randomly selected participants were selected for examination, of which 450 had cancer.

Vitamin D reduces the risk of cancer

Taking into account factors such as age, gender, smoking and family history of cancer as well as seasonal differences in circulating vitamin D, the team found that higher circulating levels of vitamin D in the blood are associated with a lower risk of cancer overall. Compared with the quartile of participants with the lowest circulating vitamin D levels, the highest quartile quartile had a 22 percent lower risk of cancer. The experts explain that there is no difference in the effect of vitamin D due to sex.

Which types of cancer protects vitamin D?

In the study of certain cancers, the Japanese research team found that the group with the highest levels of vitamin D was about 50 percent less likely to develop liver cancer than the lowest levels. There was also a weaker effect on so-called premenopausal breast cancer, but there was no clear effect on other cancers, including lung cancer, colon cancer, prostate cancer or breast cancer

There were limitations in the study?

The authors point out that the study is subject to restrictions because, for example, vitamin D was only taken at certain times. In addition, participants may simply be healthier than the general public.

Sunlight is an important component of vitamin D production. (Image: paultarasenko / fotolia.com)

The overall cancer risk was reduced

The team found that the link to lower overall cancer risk was even when liver cancer was excluded from the analysis. The reason might be that smaller effects of vitamin D on other cancers could add up when viewed together, Yamaji explains.

Protection effect is probably quite modest

The results of the current study are consistent with other studies that also found a protective effect of vitamin D against cancer deaths. Presumably, however, the effect of vitamin D is relatively modest and it is more a question of avoiding low levels than reaching high levels, the researchers concluded.

Use enough sunbeams to get enough Vitamin-D?

Critics of the study claim that the study does not clearly prove that vitamin D deficiency has a direct impact on cancer risk, or whether this risk is solely due to poor health. People should just enjoy the sun and be careful not to get sunburned, this would be enough to get enough vitamin D in the summer and to avoid vitamin D deficiency. (As)