50,000 men in the Health Professionals Follow-up Study. Participants’ average age was in the early 50s.
Study volunteers provided information on their average diet and supplement use.
People with higher levels of vitamin A tended to be older. They also exercised more and were less likely to consume alcohol or caffeine. Women with higher levels of vitamin A were more likely to use postmenopausal hormones.
Nearly 4,000 people ended up with squamous cell skin cancer during more than 25 years of follow-up, the findings showed.
Average daily vitamin A intake was around 7,000 I.U. daily for the lowest group in both studies. The highest group in both
