April 11, 2000 (Cleveland) -- For women, especially middle-aged ones, an orange a day may keep gallstones away.
A researcher from the University of California in San Francisco says that a study of more than 7,000 women and 6,000 men suggests that higher levels of vitamin C in the blood -- an increase that could be achieved by eating an extra orange each day -- offers women protection against gallbladder disease.
The protection, Joel A. Simon, MD, tells WebMD, was only seen in women, and that may be because women are more likely to be afflicted with this painful disease, which causes abdominal cramping. The typical patient, says Simon, is "fair, fat, forty, and fecund," or fertile. "This is a disease of obese white women," he says.
Simon says that studies in animals have suggested that vitamin C might boost the body's ability to digest dietary fat. High levels of dietary fat cause bile acid, which is produced by the liver and stored in the gall bladder, to become oversaturated with cholesterol. The cholesterol in bile eventually hardens into gallstones. It is these "stones" that cause the pain that is a hallmark of gallbladder disease.
Simon says his study found that vitamin C offered protection against both known gallbladder disease and undetected gallstones, in which the patients had gallstones but had reported no abdominal pain, he says.
The study's findings suggest "that it would be prudent to increase dietary consumption of fruits and vegetables, particularly those fruits and vegetables that are high in vitamin C," says Simon. The study is published in the current issue of Archives of Internal Medicine.
It's possible, Simon says, that high levels of vitamin C in the blood might be an indicator of an overall healthy diet, although the researchers controlled for differences in total intake of calories, fat, fiber, and alcohol.
Simon says that he knows that this study "adds to a long list of vitamin C studies making headlines recently." The many studies may be confusing to both doctors and patients, he says.
For instance, James H. Dwyer, PhD, a professor of preventive medicine at the University of Southern California, reported in early March that a study of 500 men had suggested that the use of vitamin C supplements promotes the type of artery thickening that is associated with stroke.
On the positive side, a study in the March 28 issue of Neurology suggested that taking vitamin C and E supplements may protect against dementia and improve thinking ability in the elderly. The same week, another study, reported at a meeting sponsored by the American Cancer Society, suggested that taking vitamin C supplements while undergoing radiation or chemotherapy might interfere with how well those treatments work.
Faced with these contradictory findings, Simon says, "the public health message is that we should recommend at least five servings of fresh fruits and vegetables for everyone. Women may consider consuming a slightly higher level of fresh fruits and vegetables that are high in vitamin C.
"I think the overall message continues to be that there is a benefit to vitamin C, although there are some studies that seem to suggest that high levels may not be beneficial."