Osteomalacia is softening of the bones. It most often occurs because of a problem with vitamin D, which helps your body absorb calcium. Your body needs calcium to maintain the strength and hardness of your bones.
Vitamin D is a fat-soluble vitamin. Fat-soluble vitamins are stored in the body's fatty tissue and liver.Read Article Now Book Mark Article
In children, the condition is called rickets.
A lack of the proper amount of calcium in the blood can lead to weak and soft bones. Low blood calcium can be caused by low vitamin D level in the blood.
Vitamin D is absorbed from food or produced by the skin when exposed to sunlight. Lack of vitamin D produced by the skin may occur in people who:
- Live in climates with little exposure to sunlight
- Must stay indoors
- Work indoors during the daylight hours
- Wear clothes that cover most of their skin
- Have dark skin pigmentation
- Use very strong sunscreen
You may not get enough vitamin D from your diet if you:
- Are lactose intolerant (have trouble digesting milk products)
- Do not eat or drink milk products (more common in older adults)
- Follow a vegetarian diet
- Are not able to absorb vitamin D well in the intestines, such as after gastric bypass surgery
Vitamin D deficit
Because vitamin D is essential for the body's utilization of calcium, a deficiency may result in severe loss of calcium and consequently a softening and weakening of bones.
Other conditions that may cause osteomalacia include:
- Cancer -- rare tumors that cause low phosphate level in the kidney
- Kidney failure and acidosis
Acute kidney failure is the rapid (less than 2 days) loss of your kidneys' ability to remove waste and help balance fluids and electrolytes in your b...Read Article Now Book Mark Article
- Lack of enough phosphates in the diet
- Liver disease -- the liver cannot convert vitamin D to its active form
- Side effects of medicines used to treat seizures
- Bone fractures that happen without a real injury
- Muscle weakness
- Widespread bone pain, especially in the hips
Symptoms may also occur due to low calcium level. These include:
Exams and Tests
Blood tests will be done to check vitamin D, creatinine, calcium, phosphate, electrolytes, alkaline phosphatase, and parathyroid hormone levels.
The phosphorus blood test measures the amount of phosphate in the blood.Read Article Now Book Mark Article
Bone x-rays and a bone density test can help detect pseudofractures, bone loss, and bone softening. More importantly, osteomalacia can look like weakening of the bones from osteoporosis on bone density testing.
Bone density test
A bone mineral density (BMD) test measures how much calcium and other types of minerals are in an area of your bone. This test helps your health care...Read Article Now Book Mark Article
Osteoporosis is a disease in which bones become fragile and more likely to break (fracture).Read Article Now Book Mark Article
In some cases, a bone biopsy will be done to see if bone softening is present.
Treatment may involve vitamin D, calcium, and phosphorus supplements taken by mouth. People who cannot absorb nutrients well through the intestines may need larger doses of vitamin D and calcium. This includes people who have some types of weight loss surgery.
People with certain conditions may need regular blood tests to monitor blood levels of phosphorus and calcium.
Some people with vitamin deficiency disorders will get better within a few weeks. With treatment, healing should happen within 6 months.
Symptoms can return.
When to Contact a Medical Professional
Call your health care provider if you have symptoms of osteomalacia, or if you think that you may be at risk for this disorder.
Eating a diet rich in vitamin D and calcium and getting sufficient exposure to sunlight can help prevent osteomalacia due to vitamin D deficiency.
Brent Wisse, MD, board certified in Metabolism/Endocrinology, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
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Demay MB, Krane SM. Disorders of mineralization. In: Jameson JL, De Groot LJ, de Kretser DM, et al, eds. Endocrinology: Adult and Pediatric. 7th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 71.
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