Vitamins are essential for the body and are considered healthy. So healthy that some studies show that certain vitamins can prevent cancer and other serious diseases. Vitamins have to be supplied to the body from outside – for example through food – because the body cannot produce them to meet its needs.
But the motto with vitamins shouldn’t necessarily be “a lot helps a lot”: With vitamins, if you take nutritional supplements, for example, overdoses can occur, which can have serious consequences for the body. One such side effect of certain vitamins can be that the risk of lung cancer increases. You can read what’s behind it and what experts warn about here.
Vitamins: Oversupply increases the risk of cancer
It is said that a diet rich in vitamins is actually a good and healthy way to reduce your own risk of cancer. According to the German Cancer Research Center, daily vitamin D intake could, for example, reduce cancer mortality in the population by twelve percent.
But not all vitamins work like vitamin D. According to the German Cancer Society, the hope has long been derived from the antioxidant effect of certain other vitamins that cancer can be prevented through increased intake of the corresponding vitamins and substances. But experts point out that there is too little evidence: not all mechanisms and effects of antioxidants on the body are known.
The German Cancer Society therefore only considers additional intake of nutritional supplements containing vitamins to be useful if special circumstances exist. These include pregnancy or an illness in which the absorption of substances such as vitamin D or calcium in the gastrointestinal tract is impaired. In Germany, this only applies to a few vitamins and minerals. Oversupply can be harmful and even increase the risk of cancer, warns the German Cancer Society.
Lung cancer: This vitamin increases the risk
A study published in 2019 showed an increased risk of lung cancer due to excessive doses of vitamin B12, warns the cancer society on its internet portal. It is important to understand that vitamin B12 itself does not cause cancer, but rather that the growth of existing cancer cells can be increased when very high doses of this vitamin are administered. The German Cancer Society therefore recommends that you determine the serum vitamin B12 level before taking it and have a medical examination. The effects of vitamin B12 are still being researched.
Another study from the Journal of Clinical Investigation from 2023 also suggests that the risk of developing a malignant tumor in the lungs can be increased by taking additional vitamins. These are vitamin A, the water-soluble vitamin C and vitamin E – the so-called antioxidants. Among other things, they are responsible for healthy skin, teeth, gums, bones and vessels – but they also activate a mechanism that is useful for cancer cells.
Cancer risk: This is how vitamins benefit the tumor
According to the research, cancer tumors form new blood vessels thanks to the vitamins. This would provide them with better nutrients and grow faster. According to the study authors, antioxidants are not a problem in normal food such as fruit or vegetables. However, it is better to avoid appropriate nutritional supplements such as pills, drops or drinks containing vitamins – especially since many manufacturers lure you with advertising lies.
