Good news for those who take vitamin supplements: people who take a multivitamin and vitamin E nearly every day for 10 years seem to have a slightly lower risk of death from heart disease, study findings hint.
Those who take vitamin E and C supplements may also have a lower risk of death overall in a five-year period, while those who take vitamin C may have a lower risk of death from cancer, note study authors Dr. Gaia Pocobelli, at Fred Hutchinson Cancer Research Centre in Seattle, Washington, and colleagues.
Vitamins E and C are antioxidants that are thought to protect against damage the body's cells, but scientists have "no clear evidence" that their use staves off death.
While the findings of the current study back earlier studies, many of the decreased risks are small, and may have more to do with other healthy behaviours in which people who take vitamins are likely to take part, the authors are quick to add in their report in the American Journal of Epidemiology.
How the study was done
The team surveyed 77 719 men and women in Washington State who were between 50 and 76 years old. Overall 67, 47, and 48% of the study group had ever used multivitamins, vitamin C, and vitamin E supplements, respectively.
Overall, there were 3 577 deaths in the group over five years. Among those who did not use vitamins, there were 350 deaths from heart disease, while there were 519 deaths among those who used vitamins between a few days and seven days per week.
After adjusting for gender and age, lifestyle, diet, and medical conditions, the researchers saw no differences between non-users and those who used multivitamins for zero to two days, three to five days, or six to seven days per week on average over 10 years.
By contrast, they saw slightly decreased risk for death from heart disease among those reporting the most frequent multivitamin use.
What the study revealed
When the researchers looked at vitamin C use, those who took more than 322 milligrams per day had a slightly decreased overall and cancer-related risk of death within five years, compared with non-users. Those with a history of heart disease who took this level of vitamin C had slightly decreased risk for death from heart disease.
Compared with non-users, men and women reporting more than 215 milligrams per day of vitamin E per day - roughly the amount found in a typical supplement -- had slightly decreased total and heart disease-related risk of death. The investigators saw no association between cancer death risk and vitamin E intake.
Even though the study took lifestyle into account, the authors that many of the findings "should be interpreted cautiously because healthy behaviours" - some of which may not have been measured - "tend to be more common in supplement users than in nonusers." – (Reuters Health, August 2009)