Vitamin D: A double-edged sword in the fight against osteoporosis?

April 23, 2012

Vitamin D is renowned for its role in creating strong bones and is a key regulator of serum calcium levels. Calcium is primarily obtained through diet and absorbed through the intestine and into the blood stream. In addition to building bone, calcium is required for a variety of important physiological processes. Vitamin D, which is detected by receptors in bone and intestinal cells, regulates the level of calcium in the blood stream and determines how much should be stored in the skeleton. Several recent clinical trials have examined the effects of vitamin D supplements on the prevention of bone fractures in the elderly; however, the results of these trials have not offered a consensus on the efficacy of these supplements.

In this month's issue of JCI, Dr. Geert Carmeliet and colleagues at the University of Leuven in Leuven, Belgium, investigated how vitamin D affects the skeleton when serum calcium levels are depleted. Using mice that lack the intestinal vitamin D receptor, the researchers showed that the mice still had normal serum calcium levels even when given a low-calcium diet. Additional experiments demonstrated that vitamin D stimulated to produce factors that removed calcium from bone in a process known as in order to maintain normal serum calcium levels. Thus, while vitamin D is important for maintaining serum calcium levels, it can also promote .

In an accompanying article, Dr. Cathleen Colón-Emeric and Dr. Kenneth Lyles of Duke University Medical Center in Durham, North Carolina, discuss the clinical implications of this investigation as well as how these findings may explain clinical trial results where vitamin D supplements failed to prevent fractures in elderly patients and, in some cases, were correlated with increased fracture rates.

Explore further: Vitamin D deficiency high among trauma patients

More information: Normocalcemia is maintained in mice under conditions of calcium malabsorption by vitamin D–induced inhibition of bone mineralization, Journal of Clinical Investigation (2012).

Related Stories

Vitamin D deficiency high among trauma patients

February 7, 2012
New research presented at the 2012 Annual Meeting of the American Academy of Orthopaedic Surgeons (AAOS) found that 77 percent of trauma patients had deficient or insufficient levels of vitamin D.

Vitamin D intake may be associated with lower stress fracture risk in girls

March 5, 2012
Vitamin D may be associated with a lower risk of developing stress fractures in preadolescent and adolescent girls, especially among those very active in high-impact activities, according to a report published Online First ...

Recommended for you

Breathing dirty air may harm kidneys, study finds

September 21, 2017
Outdoor air pollution has long been linked to major health conditions such as heart disease, stroke, cancer, asthma and chronic obstructive pulmonary disease. A new study now adds kidney disease to the list, according to ...

Excess dietary manganese promotes staph heart infection

September 21, 2017
Too much dietary manganese—an essential trace mineral found in leafy green vegetables, fruits and nuts—promotes infection of the heart by the bacterium Staphylococcus aureus ("staph").

Being active saves lives whether a gym workout, walking to work or washing the floor

September 21, 2017
Physical activity of any kind can prevent heart disease and death, says a large international study involving more than 130,000 people from 17 countries published this week in The Lancet.

Frequent blood donations safe for some, but not all

September 21, 2017
(HealthDay)—Some people may safely donate blood as often as every eight weeks—but that may not be a healthy choice for all, a new study suggests.

Higher manganese levels in children correlate with lower IQ scores, study finds

September 21, 2017
A study led by environmental health researchers at the University of Cincinnati (UC) College of Medicine finds that children in East Liverpool, Ohio with higher levels of Manganese (Mn) had lower IQ scores. The research appears ...

One e-cigarette with nicotine leads to adrenaline changes in nonsmokers' hearts

September 20, 2017
A new UCLA study found that healthy nonsmokers experienced increased adrenaline levels in their heart after one electronic cigarette (e-cigarette) with nicotine but there were no increased adrenaline levels when the study ...

2 comments

Adjust slider to filter visible comments by rank

Display comments: newest first

spiritosl
4 / 5 (1) Apr 25, 2012
The headline "Vitamin D: A double-edged sword in the fight against osteoporosis?" is definitely wrong.
If you deplete calcium in the food then the only source of Ca is the bones and the vitamin D3 at higher concentrations improves the stability of Ca+ level in the blood. The only source of Ca to maintain Ca level in blood is the Ca in the skeleton. Then you get osteoporosis in the poor malnutried animal (and humans)
Seems to be an odd experiment that doesn't prove anything IRL.
Don't forget that vitamin D3 is essential and at the high latitude where I live (61ºN) sun is a good but insufficiennt source of vitamin D3 but in a short summer. Thus I have 50 000 IU vitamin D3 per week to stay healthy. There are reports showing 100 000 IU of vitamin D per day for a year is nontoxic. So have enough (at least 5 000 IU/day) vitamin D3!
dutchman
not rated yet Apr 25, 2012
According to recent research at various medical universities, vitamin D3 plays a crucial role in the prevention of various types of CANCER. This was broadcast in a series of presentation on the University of California TV (UCTV.edu) The recommendation was 10,000 IU per day, and NO level of toxicity has been found. 10,000 IU per day for life may wipe out cancer altogether!

I think this is at least as important (if not more so) than osteoporosis.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.