Can Vitamins Cause Cancer? Viral Claims of Risk Increase May Be Bunk
Published on November 2, 2023, at 12:54 p.m. ET
An inflammatory new claim that taking vitamin supplements will increase your risk of cancer has generated controversy within the medical community. Dr. Mohammad Muneeb Khan, an oncologist with the UK’s National Health Service, has made the bold statement that multivitamins should carry the same warnings as cigarette packages. According to a statement from South West News Service, Khan said, “Synthetic pills contain excessive and unnecessary amounts of micronutrients that far exceed the body’s requirements. The problem is that these excess multivitamins can provide nourishment to the hundreds of cancer cells produced in our bodies every day. Normally, our body is equipped to effectively destroy these cancer cells, but it becomes a challenge when they are well-fed and able to multiply rapidly.”
These claims have sparked concern among the estimated 52% of US adults who use at least one dietary supplement, with 31% reporting the use of multivitamin-mineral supplements. Khan’s assertion is based on a study conducted in 1996, which involved more than 18,000 smokers, former smokers, and individuals exposed to asbestos.
The study, known as the Beta-Carotene and Retinol Efficacy Trial (CARET) and published in the New England Journal of Medicine, examined the effects of high doses of beta carotene and retinol (vitamin A) on the prevention of lung cancer. The study authors issued a warning stating, “The combination of beta carotene and vitamin A had no benefit and may have had adverse effects on the incidence of lung cancer and the risk of death from lung cancer.” As a result of these alarming findings, especially the 28% increase in lung cancer incidence among participants, the CARET study concluded nearly two years earlier than planned.
Khan further supports his claim by stating, “Research also indicates a correlation between daily supplement use, including vitamin A and vitamin B complex (such as B1, B6, and B12), and an increased risk of various types of cancer. While research on other vitamins is currently lacking, it is reasonable to assume they may have similar effects.”
Several other studies have also found negative effects associated with certain doses of multivitamins. For example, a 2022 study discovered “slightly higher risks of overall, prostate, and lung cancer, as well as leukemia, were observed for greater multivitamin use in men, with a higher risk of oropharyngeal cancer in women.” The US Preventative Services Task Force advises against taking beta carotene and vitamin E supplements, as they can increase the risk of specific types of cancer and death among healthy adults without special nutritional needs.
However, experts emphasize that most vitamin supplements are generally safe at recommended doses and can offer some benefits. The Linus Pauling Institute at Oregon State University stated, “Vitamins do not cause cancer!” in a 2015 headline. The authors of the institute’s report explained that vitamins and minerals consumed at doses recommended by the Institute of Medicine, known as the Recommended Dietary Allowance or RDA, are beneficial. On the other hand, excessive doses can have adverse health effects and potentially become harmful. The report also highlights the Physicians’ Health Study II, one of the largest and most meticulously conducted trials on multivitamins. The study found that daily use of multivitamins over 11 years reduced total cancer incidence by 8%, surpassing the effectiveness of any pharmaceutical drug to date.
Respected medical groups share a similar viewpoint. Dietitians at the University of Michigan Rogel Cancer Center assert that the focus should not solely be on supplements but rather on maintaining a healthy diet rich in whole grains, vegetables, fruits, and legumes. They argue that a balanced diet provides the necessary nutrients to prevent cancer and other chronic diseases. They also highlight the importance of addressing other risk factors, such as maintaining a healthy BMI.
In conclusion, while the claim that vitamins cause cancer has caused a stir, it is important to assess the quality of evidence and consider the overall benefits and risks associated with vitamin supplement use. A balanced and informed approach, including consultation with healthcare professionals, is critical in making decisions about dietary supplementation.
Original Source: New York Post
