A low level of vitamin D is among the causes of osteomalacia, a nutritional deficiency disorder that leaves bones weak, soft and prone to fractures. Elderly adults have an increased risk of osteomalacia, known as rickets when it occurs in children. A lack of vitamin D in your diet can interfere with bone formation by reducing your absorption of calcium. Adequate amounts of vitamin D from foods or supplements and increased exposure to sunlight may help restore normal bone mineralization.
Significance
Vitamin D, a fat-soluble nutrient, allows your digestive tract to absorb calcium, one of the primary minerals that make up bone structure. Vitamin D also supports the cycle of bone formation by maintaining normal levels of calcium and phosphate in your blood. When your skin is exposed to sunlight, your body synthesizes a certain amount of vitamin D. Salmon and other fatty fish, fish oils, egg yolks and fortified milk are dietary sources of this nutrient. With osteomalacia, your bones retain collagen, a form of connective tissue that gives them their structure, but without adequate vitamin D, your bones may lack the calcium and phosphorous that make them hard and strong. Osteomalacia can cause muscle weakness and bone pain, along with heartbeat irregularities, numbness and other symptoms related to low calcium levels. Weakened bones make you prone to fractures, especially in your spine, legs and ribs.
Causes
Inadequate vitamin D, calcium or phosphates in your diet may cause osteomalacia. Use of strong sunscreen or limited exposure to sunlight can cause low vitamin D levels, increasing your risk of developing this disorder. The elderly are more prone to osteomalacia, because their skin does not produce as much vitamin D and they spend more time indoors. Celiac disease, Crohn's disease and other gastrointestinal conditions that interfere with the absorption of vitamin D or the absorption of fat during digestion may contribute to osteomalacia. Kidney and liver disease prevent your body from processing vitamin D properly. Osteomalacia is a potential side effect of certain anti-seizure medications.
Treatment
Meeting nutritional requirements for vitamin D through dietary sources and exposure to sunlight may reverse the effects of osteomalacia if your condition is caused by a vitamin D deficiency. Your doctor may recommend vitamin D supplements, either orally, intravenously or through an injection, to bring the level of vitamin D in your blood back to normal. Calcium and phosphorus supplements may restore bone health if your serum levels of these minerals are low. Spending at least 15 minutes in the sun at least twice a week should allow your body to synthesize adequate vitamin D.
Recommendations
The recommended dietary allowance for vitamin D established by the Institute of Medicine is 600 IU for men and women ages 19 through 70. For adults over 70, the RDA increases to 800 IU. Cod liver oil has the highest concentration of naturally occurring vitamin D, offering 340 percent of the daily value, or the amount that a healthy person on a 2,000 calorie diet needs daily to maintain healthy physical function. Adding fortified milk, cereals or orange juice to your diet daily and eating fish or eggs on a regular basis will help you meet the daily requirements for vitamin D and calcium.
