What do healthy bones need? Calcium is most likely the first thing to come to mind. But a new study reinforces the evidence that vitamin D also plays an essential role in bone health. Researchers from the Children’s Hospital Boston report that a higher level of vitamin D intake may protect girls against stress fractures.
The study, published in the Archives of Pediatric and Adolescent Medicine, assessed the dairy, calcium, and vitamin D intake of over 6,700 girls aged nine to 15. Researchers followed the participants for seven years, tracking the occurrence of stress fractures, which often result from sports activities. About 4 percent of the girls developed a stress fracture over the course of the study, but those girls who had the highest level of vitamin D intake were 50 percent less likely to have a stress fracture than girls with the lowest vitamin D consumption. Contrary to what one might expect, higher calcium intake was actually linked to an increase in stress fracture risk: Those girls with the highest intake were twice as likely to develop such a fracture, a finding unexplained by the authors.
ACSH’s Dr. Ruth Kava notes that this study reminds us of the importance of vitamin D to bone health. “It doesn’t matter how much calcium you consume,” she says, “If you don’t have enough vitamin D, your body won’t be able to absorb it.” Aside from sunshine, fortified dairy products and breakfast cereals, some fish, and supplements are also good sources of vitamin D.
Friday, March 9, 2012
Vitamin D for young bones
Monday, March 5, 2012
Mouse Study Suggests Vitamin E May Weaken Bones
SUNDAY, March 4 (HealthDay News) -- Vitamin E may stimulate cells that result in bone loss, a new study suggests.
Researchers led by Shu Takeda of Keio University in Tokyo said their findings could have implications for people who take vitamin E supplements.
The researchers explain that maintaining a balance between bone-forming cells (osteoblasts) and bone-degrading cells (osteoclasts) keeps bones strong. Although prior studies had suggested that vitamin E could be beneficial for bone health, the Japanese researchers found the opposite may be true, since the nutrient seems to trigger the production of bone-eroding osteoclasts.
A U.S. expert agreed with the hypothesis.
"Bone health is a dynamic tissue and issue," said Dr. Robert Graham, an internist at Lenox Hill Hospital in New York City. "It is in a constant struggle between osteoblasts ... and osteoclasts."
Understanding this cellular battle "is crucial in understanding how vitamin E may affect our bone health," Graham said.
The new study, published online March 4 in Nature Medicine, revealed that mice deficient in vitamin E actually have higher bone mass because there is less bone breakdown. Meanwhile, healthy mice that were fed a diet with the amount of vitamin E found in typical human supplements lost bone mass.
The study has revealed "the opposite of what was traditionally believed," Graham said. "This is intriguing, because previous in vitro
Monday, February 13, 2012
No Cancer Benefit From Vitamin B, Omega-3 Supplements in Heart Patients
MONDAY, Feb. 13 (HealthDay News) -- Patients with a history of heart disease will most likely not reduce their risk for developing cancer by taking vitamin B and/or omega-3 fatty acid supplements, a new French analysis suggests.
"In the population we studied, we found no beneficial effects of either B vitamins or omega-3 fatty acids taken over five years on cancer occurrence or cancer-related death," noted study author Valentina Andreeva, who is with the nutritional epidemiology research unit at the University of Paris XIII in Bobigny, France.
Andreeva and her colleagues report their findings in the Feb. 13 online edition of the Archives of Internal Medicine.
To explore the protective potential of B vitamins and fatty acid supplements, the authors did a secondary analysis of data that had been collected in a previous study involving almost 2,000 French men and 500 women.
All were between 45 and 80 years of age, and all had experienced cardiac trouble (heart attack, unstable angina or ischemic stroke) in the year leading up to the start of the study.
In turn, the participants were divided into one of four different groups that consumed a daily supplement regimen involving various types of vitamin B and omega-3 fatty acids at "relatively low supplementation doses."
By the end of the original five-year study, 7 percent of the participants had gone on to develop some form of cancer, and just over 2 percent ultimately died of cancer. The vast majority of cancer cases (including prostate, lung, bladder and colorectal cancer) and deaths occurred among men (81 percent and 83 percent, respectively).
The team unearthed no evidence that any form of vitamin B or omega-3 fatty acid supplement improved cancer outcomes in any way.
The investigators noted that there were some indications that cancer risk might have actually gone up, specifically among women taking vitamin B and/or omega-3 fatty acid supplementation. However, the authors stressed that this observation was based on too few cases to substantiate a firm conclusion, and called for further research involving a larger pool of participants.
"The results of our study suggest that individuals should exercise caution when deciding to take dietary supplements, especially over a long period of time and without a physician's advice," advised Andreeva. "Such supplements constitute active substances and might have adverse effects in some populations. To be on the safe side, individuals should strive to achieve dietary recommendations via healthy, balanced diets."
Joseph Su, the Washington, D.C.-based program director of the division of cancer control and population science within the U.S. National Cancer Institute's epidemiology and genomics research program, said that nothing about the findings struck him as surprising.
"So far, study findings have been very inconsistent," he noted. "But most supplement studies, if anything, have shown no beneficial effect whatsoever. Just like this one. So, I don't think there's anything that can really back up the idea that these supplements can prevent cancer."
However, Vicky Stevens, strategic director of laboratory services at the American Cancer Society in Atlanta, expressed some reservations about the French analysis.
"Compared with other trials, they used much lower levels of supplements," she noted. "From the B-vitamin point of view, dramatically lower. So, it could be argued that they just weren't using high enough levels of supplements to see any effects," Stevens suggested.
"And they used a natural form of folate