A coffee habit of more than four cups a day could be shortening your life, research suggests.
Drinking large amounts of coffee was found to raise the chances of men and women up to the age of 55 dying from any cause.
Consuming more than 28 cups a week increased their death rates by more than half, while having no effect on older people.
Younger people in particular should avoid heavy coffee drinking, the US investigators warned.
The research, published in the journal Mayo Clinic Proceedings, was based on data from a lifestyle study of 43,727 adults in the United States aged 20 to 87.