High intake of vitamin E appears to prevent liver cancer, Chinese scholars find. An article published online in the Journal of the National Cancer Institute by Xiao-Ou Shu, MD, PhD, PhD, of the Vanderbilt University Center for Epidemiology in Nashville, and colleagues, says that a high intake of vitamins in the diet of people aged 40-70 years significantly reduces the risk of cancer (trend test P=0.01), and intake of vitamin E supplements reduced the risk by almost half (HR 0.52, 95% CI 0.30 ~ 0.90). The researchers believe that if the conclusions are confirmed, the above findings have the potential to open up a new battlefield for cancer prevention. Wang Jun t, Intensive Care Unit, Nanping First Hospital Because the link between dietary factors and vitamin supplementation and liver cancer development is unclear, Shu and colleagues evaluated data from a study of 132,837 patients collected from the Shanghai Women’s Health Study and the Shanghai Men’s Health Study. The researchers used a food frequency questionnaire to assess vitamin intake in the diet and dietary supplements. During the follow-up phase, 267 patients developed liver cancer, with a mean time to liver cancer of 10.9 years in women and 5.5 years in men. The researchers found that high levels of dietary vitamin E intake reduced the risk of liver cancer, with patients in the two highest dose quartile groups having a significantly lower risk of liver cancer (HR 0.66, 95% CI 0.46 ~0.94 and HR 0.60, 95% CI 0.40 ~0.89, respectively; p=0.01 for trend test). Taking vitamin E supplements reduced the risk of liver cancer by almost half compared to those who did not use vitamin E supplements (HR 0.52, 95% CI 0.30 ~ 0.90).
Further analysis showed that the association was stronger in the female subject population. The researchers noted that the findings remained consistent among patients with or without liver disease and with or without a family history of liver cancer. The potential preventive effects of vitamins may be related to their ability to prevent DNA damage, enhance DNA repair, prevent lipid peroxidation, inhibit activation of carcinogens or enhance the function of the immune system. As for other types of vitamins, the researchers found that vitamin C appeared to increase the risk of liver cancer (HR 1.96, 95% CI 1.29 ~ 2.98 ), and multivitamins increased the risk of liver cancer in men (HR 1.84, 95% CI 1.13 ~ 2.98). However, concomitant use of both vitamin C and E supplements increased the risk of liver cancer in those with a history of liver disease and a family history of liver cancer (P values 0.01 and 0.06, respectively). Shu and his colleagues also noted that vitamin C and other vitamins did not increase the incidence of liver cancer when consumed from food. There was also no correlation between the use of vitamin B or calcium supplements and the risk of liver cancer. Study shortcomings include the relatively short follow-up period, reliance on food frequency questionnaires to evaluate dietary intake, lack of information on specific doses of vitamin intake, and inability to exclude unmeasurable confounding factors such as hepatitis B and C and other risk factors. The investigators suggest that vitamin E may play an important role in liver cancer prevention in Chinese patients.
Source: Clove Garden Author: arsense