Vitamin D Deficiency and its Implications

Courtesy: Prof Nabil Ebraheim, University of Toledo, Ohio, USA

VITAMIN D DEFICIENCY

Vitamin D is important for the proper maturation and development of bone and it also boosts our immunity.

• We use the term “deficiency” if the vitamin D level is below 20 ng/ ml.
• We use the term “insufficiency” if the vitamin D level is 20 – 30 ng / ml.
• Vitamin D level greater than 30 ng/ ml is adequate.

Functions of Vitamin D:

• The main function of vitamin D is absorption of calcium and phosphate from the intestines.
• Through increased absorption of calcium and phosphate from the intestine it increases bone resorption of calcium and phosphate.
• Impaired mineralization can lead to rickets in the young and osteomalacia in adults.

Sources of Vitamin D:

• Vitamin D comes from diet, exposure to the sun and from supplements.
  In a healthy, young adult, the recommended daily allowance for vitamin D is 400 – 800 IU per day.
• Vitamin D is synthesized in the skin epithelium under UVB radiation. It undergoes two hydroxylations, 25 in the liver and 1-alpha in the kidney, to form the active form of 1, 25 Dihydroxy vitamin D .
• This crude vitamin D gets activated in the liver.
• Staying home limits the amount of time spent in public, so the amount of vitamin D that is received through the sun is less.
• You will need to get more vitamin D from other sources such as from diet and supplements.

Foods rich in vitamin D:

• Found in oily fish such as salmon, sardines, herring, and mackerel.
• Egg yolks
• Mushrooms.
• Dairy products
• Meat

1, 25 (OH)2 – Vitamin D is the active form vitamin .

Features of Vitamin D deficiency:

The symptoms of vitamin D deficiency are subtle and non-specific, and the majority of people are not aware of it.

• Depression
• Fatigue / tiredness
• Decreased physical activity
• Muscle weakness
• Hair loss
• Bone pain
• Sleeping disorders
• Reduced bone mass
• Slow healing or nonunion of fractures
• Cardiovascular disorders

Investigation

• The 25 Hydroxy vitamin D test is done in patients who are suspected to have low vitamin D levels.
• This is because it has a long half life (2 – 3 weeks) and has a higher concentration, so it is a good test for vitamin D status

Management

• Adults with a vitamin D deficiency should be given 50,000 IU of vitamin D3 once a week for eight weeks with the goal of achieving blood levels of vitamin D 25-hydroxy above 30.
• This is followed by maintenance therapy between 1500 – 2000 lU daily which can be acquired from diet or supplement sources.