By Dr Veerachai Sachdev, Part Time Medical Instructor at Department of Family Medicine, Ramathibodi Hospital, Mahidol University.
It has been estimated that over 1 billion people globally suffer from Vitamin D deficiency.
Living in a vibrant city like Bangkok with plenty of sunshine all year round, does not protect us from having a deficiency in Vitamin D, especially if you spend most days indoor and not getting at least 15- 20 minutes daily walk in the sun.
Why is Vitamin D important for our health?
- Helps in the absorption and retention of calcium and phosphorus ensuring that our bones stay strong and healthy.
- Prevents the excessive release of parathyroid hormones which makes our bones thin and brittle.
Vitamin D plays a vital role towards our immune system and have role in preventing infections including the common cold and flu viruses. The health professional – follow-up study where more than 50,000 men who were healthy had Vitamin D levels checked and followed over a span of 10 years found that men who were deficient in Vitamin D were twice as likely to have a heart attack compared to men who had adequate levels of Vitamin D.
What are the sources of Vitamin D?
Sunlight – Our body produces vitamin D from cholesterol, activated by a process of skin exposed to direct sunlight, however if you may have an increased risk of deficiency if you have a darker skin tone, overweight and old.
Dietary sources – Few foods have high amount of vitamin D, these includes diary products, breakfast cereals, salmon and tuna fish.
Supplements – As there are limited amounts of foods that have high amounts of Vitamin D, and if you adhere to a strict Vegan or Vegetarian diet you may run a risk of being vitamin D deficiency. Two forms of vitamin D are used in supplements: Vitamin D2 “ergocalciferol” and Vitamin D3 “cholecalciferol”. It would be important to know your Vitamin D levels prior to taking any additional supplements.
How much Vitamin D is needed?
The Institute of Medicine recommends dietary allowance of 600IU units of Vitamin D per day. For bone health and chronic disease prevention, a higher dose of Vitamin D may be advisable. Whilst sun exposure produce vitamin D, too much exposure could increase the risk of skin cancer, the American Academy of Dermatology recommends using a sunscreen of at least SPF 30 when in the sun.
It is important to speak to your family doctor about your individual needs.
Dr Veerachai Sachdev MBBS FRACGP LLM Clin Dip PallMed – Part Time Medical Instructor at Department of Family Medicine, Ramathibodi Hospital.
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 Institute of Medicine. Dietary reference Intakes for Calcium and Vitamin D. Washington, D.C.: National Academies Press, 2010.