Popping a multivitamin pill each day can reduce a man's risk of cancer, a large study has found.
Scientists in the US who monitored almost 15,000 men for 11 years said those who took the pills were 8% less likely to develop cancer of any kind.
The "modest" reduction is thought to mirror the benefits of eating a healthy diet high in fruit and vegetables.
Multivitamins contain a wide range of nutrients that might be missing from a less than ideal diet.
Researcher Howard Sesso, from Brigham and Women's Hospital in Boston said: "Many studies have suggested that eating a nutritious diet may reduce a man's risk of developing cancer.
"Now we know that taking a daily multivitamin, in addition to addressing vitamin and mineral deficiencies, may also be considered in the prevention of cancer in middle-aged and older men."
The Physicians Health Study II (PHS II) trial involved male American doctors who received either a daily multivitamin tablet or an inactive placebo pill.
Over an average 11.2 years, a total of 2,669 cancers were diagnosed, including 1,373 cases of prostate and 210 cases of bowel cancer.
During the follow-up period, 2,757 (18.8%) of the men died, including 859 killed by cancer. Compared with men not taking multivitamins, pill users experienced an 8% reduction in total cancer incidence.
Results of the study were presented at the Frontiers in Cancer Prevention Research meeting in Chicago and also published in the Journal of the American Medical Association.