Osteomalacia

In order to make healthy bone, your body needs calcium and vitamin D. Osteomalacia is a condition in which your bones become soft because of a lack of calcium and phosphate, often due to not getting enough vitamin D.

In children, whose bones are still growing, this condition is called rickets.

Bones in osteomalacia. 

Causes

Your body needs vitamin D in order to absorb calcium and phosphorus, which are both necessary for making strong, healthy bone. When vitamin D, calcium or phosphorus levels are poor, bones can become soft and prone to fractures.

Vitamin D is found in some foods, particularly fish and dairy products (see below for details). However, in most people, vitamin D is produced by the body. Skin cells make a precursor of vitamin D when exposed to sunlight.

The precursors of vitamin D obtained from food and skin cells then get processed in the liver and kidneys to produce the active form of vitamin D.

Vitamin D synthesis in the body. 

Most people have enough vitamin D by some combination of these two routes. However, people who eat a diet poor in vitamin D and who also are not exposed to enough sunlight may be deficient in vitamin D. Problems in processing vitamin D in the gastrointestinal tract, liver or kidneys can also cause vitamin D deficiency.

Signs and symptoms

Signs and symptoms of osteomalacia include:

• Increased risk of fractures;
• Fractures that happen without injury;
• Widespread bone pain and tenderness, especially in the pelvis and lower back. Even slight pressure on bone can cause considerable pain;
• Difficulty in walking, walking with a waddle, and;
• Muscle weakness.

Methods for diagnosis

Your doctor will diagnose osteomalacia based on your symptoms and the results of tests, including:

• Blood tests to check your vitamin D and calcium levels;
• X-rays;
• Bone density tests, and;
• A bone biopsy - obtaining a small sample of your bone for testing.

Types of treatment

Treatment of osteomalacia focuses on you getting enough vitamin D, calcium and phosphorus in your diet and getting regular sunlight exposure. Your doctor may advise you to add certain vitamin-rich or calcium-rich foods to your diet, or to begin taking nutritional supplements.

Dietary vitamin D

Good sources of dietary vitamin D include:

• Fish - including salmon, snapper, whitefish, mackerel, trout and herring;
• Whole milk, butter and margarine;
• Ricotta cheese;
• Egg yolks;
• Some types of mushrooms, such as shiitake mushrooms;
• Tofu, and;
• Foods fortified with vitamin D. These can include juices, yogurt, cereals, soy milk, almond milk and many others. Check the labelling of the package for vitamin D levels.

Exposure to sunlight

Your body needs some exposure to sunlight in order to make vitamin D. The ultraviolet radiation in sunlight (specifically UVB) activates the vitamin.

However, UVB exposure puts you at risk of skin cancer. Striking the right balance between underexposure and overexposure is not always easy. Note that your body needs only a few minutes daily of direct sunlight - in the morning or afternoon - in order to make active vitamin D.

Prognosis

If vitamin D levels return to normal, osteomalacia should go away within a few weeks to months.

Prevention

Unless there is an underlying medical condition, osteomalacia can be prevented by including enough vitamin D in your diet and getting enough sunlight.