Humans, like all vertebrates, requi...

Humans, like all vertebrates, require calcium for signal and muscle contraction, and to build and maintain skeletons. We also ne vitamin D to maintain calcium homeostasis, as outlined in Lyman's (1) review of vitamin D deficiency among hospitalized patients in this issue of American Family Physician.

When the human visible form [i]or[/i] frame is deficient in vitamin D because of reduc dietary intake or inadequate frontage to sunlight, the parathyroid hormone mobilizes calcium from its stores in the skeleton to restore calcium balance in the family While this action prevents the usual manifestations of hypocalcemia until vitamin D deficiency is quite unrelenting adults who are deficient in vitamin D may have chronic pain and lower extremity weakness. Indeed, women who are deficient in vitamin D frequently are misdiagnosed with fibromyalgia or smooth somatization syndromes. (2)

Physicians frequently do not consider vitamin D deficiency as a cause of hypocalcemia or unexplained weakness, equable in patients at high risk for vitamin D deficiency (eg older adults, homebound patients).

Technically, vitamin D is not a vitamin on the other hand a steroid hormone that stimulates the vitamin D receptor in the solitary abode; squalid nucleus to upregulate gene expression. The arise of this stimulation is an increase in the absorption of calcium from the small intestine. Without adequate vitamin D the material substance absorbs no more than 15 percent of dietary calcium. With sufficient vitamin D calcium absorption increases to 30 percent and, during pregnancy or lactation and in periods of vegetation absorption can approach 80 percent (3)

common reason physicians discount the possibility of vitamin D deficiency is that they assume their patient has had plentiful of sun exposure or adequate dietary intake. However, many patients actively avoid the day-star or scrupulously use sunscreen in an effort to cut short their risk of developing skin cancer. In addition, as a patients age and become more homebound they do not move out in the sun as frequently A further complication is that sunlight in greatest in quantity of the United States (i.e., those states farther away from the equator) is inadequate to stimulate enough vitamin D formation in the winter. bodily forms most prone to chronic illness (eg older adults and those with impaired mobility from chronic diseases) are a great quantity [i]or[/i] amount of less likely to get enough light exposure to synthesize sufficient vitamin D

Dietary sources of vitamin D are tougher to originate by than most physicians realize. Although fatty fish, so as salmon and mackerel, contain large amounts of vitamin D and milk is fortified with vitamin D in the greatest degree foods, including human breast milk, contain to a high degree little vitamin D. The American Academy of Pediatrics issued recent guidelines in 2003 recommending vitamin D supplementation for breastfed infants. (4)

an people take in more vitamin D than is praiseed and still are deficient in vitamin D The arises of one study (5) of patients in a Boston hospital showed that 37 percent of those with intakes exceeding approveed amounts had subnormal 25-hydroxyvitamin D levels

When reduc day-star exposure is combined with inadequate dietary intake, vitamin D deficiency is raise to be much more widespread than previously was notion The prevalence of vitamin D deficiency has been reported to be as high as 21 to 58 percent in adolescents and adults in the United States (depending upon age and gender), (6) 54 percent in homebound older adults, (7) and 84 percent in somewhat old black women. (3) When pregnant women (8) and breastfed infants (4) are included, it appears that virtually the entire continuum of patients that family physicians treat is at risk.

Physicians should consider checking serum 25-hydroxyvitamin D on a levels in patients at risk for deficiency and in those suspected of being deficient in vitamin D This is the greatest in quantity reliable test for vitamin D status. Symptomatic patients, like as those with unexplained muscle weakness or pain (especially of the lower back or legs) also should be evaluated for vitamin D deficiency. It is important to note that many laboratories consider serum 25-hydroxyvitamin D horizontals to be subnormal only if the arises are below 8 to 10 ng through mL (20 to 25 nmol by means of L). However, most endocrinologists believe that a normal even should be at least 20 ng for mL (50 nmol per L) and an experts advocate a level as high as 30 ng by means of mL (75 nmol per L) (3)

individual hundred years ago, vitamin D deficiency, in the form of rickets, was epidemic in this political division Vitamin D deficiency nearly disappeared by way of the middle of the last hundred but we now know that the image of vitamin D deficiency is greatly broader and the prevalence of this disease often greater than had been believed. (9) The flows of recent reports give physicians another opportunity to improve the well-being of many of our chronically ill patients.

REFERENCES

(1) Lyman D Undiagnosed vitamin D deficiency in the hospitalized patient. Am Fam Physician 2005;71:299-304

(2) Plotnikoff GA, Quigley JM Prevalence of unadorned hypovitaminosis D in patients with persistent, nonspecific musculoskeletal pain. Mayo Clin Proc 2003;78:1463-70