Excessive consumption of citrus fruits, like oranges and grapefruits, may raise the risk of melanoma, the deadliest form of skin cancer.
According the a 25-year study, citrus fruits contain compounds which make skin more sensitive to sunlight.
Dr. Walter Willet of Harvard School of Public Health and his colleagues conducted the study.
Researchers looked at more than 100,000 Americans – 40,000 men partaking in the ongoing Health Professionals Follow-Up Study and more than 60,000 women in the Nurses’ Health Study.
While only 2% of people in the study got melanoma, the risk was 36% higher in people who ate or drank at least 1.6 ounces worth of citrus daily.
Despite the concern, some of the details of the study are puzzling and complicated.
“At this point in time it is not a good idea to avoid citrus fruits,” said Dr. Willett.
The research is still ongoing, but does support the old recommendation to maintain a varied diet.
“Just because something is natural doesn’t mean that it can’t contain lots of very toxic substances,” said Willett.
“While the findings are intriguing, it’s far too soon to recommend any broad changes to grapefruit or orange consumption. Until conclusive data are available, we should continue to be cautious about protecting our skin from sun exposure,” said Dr. Gary Schwartz of the American Society of Clinical Oncology.