Vitamin D can be produced in the body through exposure to sunlight or consumed through foods and supplements.
The results of the randomized clinical trial to compare the effects of low-dose vitamin D supplementation, high doses vitamin supplementation D and placebo published in Archives of Internal Medicine .
Vitamin D plays a key role in the regulation of calcium and phosphorus absorption and maintenance of healthy bones and teeth. People who do not get enough vitamin D are susceptible to osteoporosis due to reduced absorption of calcium.
Studies have shown that nearly half of postmenopausal women with osteoporosis sustain fracture , with falling estrogen levels are also a factor in the development of osteoporosis. The prevalence of this disease suggests that vitamin D supplementation is especially important for this group.
Insufficient vitamin D also is estimated to affect about 75% of postmenopausal women in the US, according to the study authors.
The optimal level of vitamin D for bone health remains a matter of debate, however. While the Institute of Medicine (IOM) recommends levels of 20 ng / ml or more, others believe vitamin D levels should be at least 30 ng / ml.
To investigate, Dr. Karen E. Hansen of the University of Wisconsin School of Medicine and Public Health in Madison, and colleagues recruited a total of 230 postmenopausal women with low vitamin D – defined as a level of vitamin D 14 -27 ng / mL.
Participants were randomly assigned to one of three groups. One group received a high dose of cholecalciferol – a form of vitamin D – which manages and vitamin D levels are maintained at 30 ng / ml and above. The other groups received a low dose of cholecalciferol and placebo, respectively.
High dose supplementation did not decrease the total number of falls
During one year, the researchers recorded changes in calcium absorption, bone mineral density, muscle mass and tests of sitting or standing among participants.
Although the researchers observed an increase of 1% in the absorption of calcium in the high-dose group compared with 2% and 1.3% decreases in the low dose groups and placebo, respectively, the high dose was not considered to provide an overall benefit like no no differences among the three groups in the changes in bone density, muscle mass or sitting and standing evidence they were found.
Even without improvements in these areas, the authors write that supplementation with high doses of vitamin D could be justified if the number of falls is reduced, as normally precede osteoporotic fractures.
However, no differences among the three groups in the number of falls that occurred among participants, the amount of physical activity carried out or in functional status were found.
“Although we found no significant increase in bone resorption or decreases in [bone mineral density] associated with cholecalciferol at high doses, the benefits of cholecalciferol in high doses were too small to justify its routine use,” conclude the authors .
The authors note that their findings are limited by the number of people who participated in the trial. Few African Americans participated and all participants were older than 75 years or less. Results may not, therefore, be generalizable to people inadequately represented by the participants.
In an accompanying note editor, Dr. Deborah Grady, assistant editor of Archives of Internal Medicine , provides:
“It is possible that treatment beyond one year would lead to better results, but these data do not provide support for the use of replacement therapy cholecalciferol-dose higher or indeed any dose of cholecalciferol compared to placebo . ”
For more information on health benefits and recommended vitamin D intake visit Microsoft Knowledge Center of Medical News Today.