Vitamin D, also known as the sunshine vitamin plays various important roles in the functioning of our bodies. The cheapest and best source of this vitamin is the sun, available abundantly in a tropical country like India.
Foods that contain vitamin D include fish oil, fatty fish like salmon and egg yolk. Apart from this, many cereals, milk and juices are fortified with vitamin D. A lack of vitamin D is rare in developed nations, but seen fairly commonly in poor populations of developing countries.
Also read: Don’t shun the sun – Benefits of sun exposure
Vitamin D deficiency can occur in:
- People below the poverty line who cannot afford enough milk for themselves
- People who are lactose intolerant – as they avoid milk and milk products
- People who are underweight – as vitamin D is a fat soluble vitamin, it needs a certain amount of body fat to get absorbed into the body
- People who hardly ever are exposed to sunlight – for example, people working indoors for very long hours or elderly people who are bedridden and cannot go outdoors
- Children between the ages of six months and two years – this is the time when the requirement of vitamin D is the maximum due to bone growth
- People with medical conditions like kidney problems, inflammatory bowel disease and hereditary disorders like cystic fibrosis
- Exclusively breast fed babies – breast milk lacks vitamin D, so it is given to newborn babies in the hospitals in the form of drops orally
- Dark skinned children absorb less vitamin D from the sunrays
- People taking anti-seizure medicine – as this inhibits the absorption of vitamin D
Consequences of vitamin D deficiency
Vitamin D is vital for the absorption of calciumand phosphates from the food we eat. This deficiency causes a condition called osteomalacia, also known as nutritional rickets. It is because of a lack of vitamin D in the diet of the person, hence if it is diagnosed and treated on time the condition can be reversed. Rickets can also be due to kidney problems (called renal rickets) or due to a lack of phosphate (known as hypophosphatemic rickets). In this article we will limit the discussion to nutritional rickets.
Symptoms and signs of vitamin D deficiency
Rickets affects the skeleton of the body, mostly the long bones like those of the arms, thighs and legs and the skeleton.
- The breastbone may protrude
- Wrists and ankles are thicker than normal
- Bow legs are a characteristic sign of rickets
- Growth may be impaired
- Short stature – the person may be shorter than is expected
- Skull may be abnormal in shape
- Pelvis and spine may have deformities
- Muscle tone and strength is poor
- There may be bone tenderness and pain, fractures may occur after a trivial injury
- Formation of teeth is delayed and other dental deformities are seen
- Serious symptoms in which calcium and phosphate levels are very low are tetany (involuntary muscle contractions) and seizures.
Diagnosis of vitamin D deficiency
A thorough medical and nutritional history along with a complete physical examination will give confirm that rickets is the diagnosis. Investigations will confirm the diagnosis.
Investigations to diagnose vitamin D deficiency
Blood tests include serum calcium, vitamin D levels, levels of the enzyme alkaline phosphatise and levels of parathyroid hormone which plays a role in calcium and phosphate levels. In rickets, parathyroid hormone levels are elevated while those of calcium and phosphates are lowered
Kidney function is measured by blood urea nitrogen levels (BUN) and serum electrolytes.
X-rays of the thigh and leg bones are commonly done and also other bones if suspected to have signs of rickets
Treatment for vitamin D deficiency
Nutritional rickets can be corrected by administration of vitamin D and calcium as both will probably be deficient.
If bony abnormalities are seen, bracing can be done in children so that the growth occurs in a proper manner.
In some cases, bow legs correct themselves without surgery while in very advanced cases, the deformity may be permanent.
Prevention of vitamin D deficiency
Nutritional rickets can be prevented by giving out health information to expecting mothers and women who want to become parents regarding the inclusion of milk and milk products in their diet. They should be made aware of fact that as breast milk lacks vitamin D, it needs to be given. Mothers should be aware that children and adolescents who do not get enough calcium and vitamin D should also get supplements of the same to prevent rickets.
Photograph via sxc.hu
Written by Dr Nisreen Nakhoda, General Physician
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Vitamin D deficiency – Risks, consequences and treatment is a post from: mDhil
