Feb. 8, 2001 -- Want to make sure that your bones stay healthy and strong? Then start "boning" up on your vitamin C. Researchers have found that postmenopausal women who took vitamin C supplements had a higher bone density than those who didn't. The highest bone densities were also found in the women who were taking more than 1,000 mg/d.
Our body needs vitamin C for a number of reasons, one of them being collagen production. Collagen is a substance that forms the body's connective tissues, which includes bones. Scientists have previously looked at the connection between vitamin C and bone development, but they were unsure whether or not it would help increase bone density.
But in a study which appears in the January issue of the Journal of Bone and Mineral Research, California researchers have found that this common vitamin may, indeed, boost bone mineral density. California researchers looked at almost 1,000 postmenopausal women, of whom nearly a third regularly supplemented with vitamin C. The women took between 70 and 5,000 mg/d. Around half of the women took 500 mg, and a quarter of them 1,000 mg, on a daily basis. The National Institutes of Health currently recommends 100-200 mg/d for healthy nonsmokers.
The researchers measured bone density in four different areas of the body and found that the women who were taking vitamin C had bone mineral density levels that were approximately 3% higher than the others. The women who supplemented with vitamin C were also more likely to be using estrogen, and taking calcium and multivitamin supplements. Combining estrogen, calcium, and vitamin C appeared to produce the highest bone density in all four body sites.
"An individual who is at risk needs to do preventive strategies," says study author Diane L. Schneider, MD, an associate professor of medicine at the University of California, San Diego. "A significant difference was seen with people taking vitamin C alone, at the hip."
More than half of the women had been taking vitamin C supplements for over 10 years, but the length of time that vitamin C was used did not seem to affect bone density levels. However, they found that dosage made a difference. Women who took 1000mg or more had the highest levels of bone mineral density.
"This is a very interesting article," says Lawrence Raisz, MD, a professor of medicine at the University of Connecticut Health Science Center in Farmington. He points out that before people knew about vitamin C, those who were deficient in it suffered from a deadly disease called scurvy.
"Scurvy is a bone disease, because the collagen, which is the matrix of bone, wasn't adequately made in those who were deficient in vitamin C," Raisz tells WebMD. "So bone was very much at risk when you had a vitamin C deficiency."
But this is a little different, he says, because these women are not really deficient and vitamin C is being used as a treatment.
Raisz, who was not involved in the study, also notes that people who do take vitamin C supplements are going to have a different health consciousness, and they're going to be a little different from the public at large. "They may have a better diet, or be more physically active, or just be more concerned about all aspects of their health," he says. "They may be more compliant with their medication, such as being more compliant with their calcium and estrogen. People who comply in a study tend to be healthier."
Vitamin C alone cannot replace estrogen therapy and calcium supplements, but it does appear to enhance their effect, according to Schneider.
"We could not determine the optimal dose from this study," says Schneider, "But the individuals who were taking a gram a day had higher bone density than those who were taking less than that."
Raisz feels that more research is still needed. What we need to do now is find out exactly how the vitamin C works to increase bone density, he says, and we need to do more studies where we can see how it affects bone turnover, bone density or even prevention of fractures.
"A good study would be with people who are on calcium, estrogen, and vitamin D for prevention of osteoporosis, and give them a standardized dose of vitamin C, probably in the range of 1,000 mg and see how they do," he says. "This is an extremely important issue to be pursued."
So for now, should women start supplementing with vitamin C? It's something that women can consider doing, says Schneider. "We certainly know that it has other positive effects. It's not only for bones. And this may be reassuring to women who have been taking vitamin C, that it may be beneficial to their bones."