Sunlight is the best source of Vitamin D (Vit D) and the popular belief is that countries drenched with sunlight have individuals with high Vit D levels. However, in a sunshine rich land such as India, the urban Asian Indians have a Vitamin D deficiency rate of 60-90% (1,2).
Sounds ridiculous but it is true. One of the factors for the low Vit D level is less exposure of the skin to direct sunlight.
So why is Vit D important?
● strengthens our muscles and bones.
● reduces pain and improves the physical performance.
● helps to keep the tiredness and depression away.● prevents weight gain, diabetes, hypertension and other cardiovascular diseases.
How can Vit D levels be increased in the body?
Levels of Vit D below 20ng/ml in blood are marked as deficient.
Ideal Vit D levels are above 30ng/ml and in the range between 40-50ng/ml (3).
Sunlight is the most expensive drug that could be taken free of cost.
Skin pigmentation (melanin) shields against UV- B rays hence dark skinned individuals need longer sunlight exposure to activate Vit D production.
For individuals with dark skin (such as Asian Indians) a minimum 30 minutes of exposure of the skin to sunlight, preferably between 10am to 2pm twice a week is advised.
During this time the ultraviolet B radiation (wavelength 290-315 nm) is the highest. The UV- B rays penetrate the skin and convert 7-dehydrocholesterol to Vit D.
For those with light skin (such as Europeans), a 15 minute of exposure to sunlight is recommended.
Foods rich in Vit D are fishes like Salmon, Sardines, Tuna etc.
Cod liver oil is also a good source.
Nowadys milk, juices, yogurt and butter are also spiced with Vit D.
Studies comparing Vit D levels between Indian immigrants and Europeans living in Western countries with less sunlight indicate that Vit D is much lower in the Indians. It is advisable that Indians living in colder regions may consume Vit D supplements particularly during the winter time (Nov and April).
Is Vit D important for sportspersons?
Vit D increases muscle strength, muscle size, reaction time, balance, coordination and endurance. All these factors are critical for a person doing regular sports. (4,5)
Studies suggest that outdoor athletic performance is at peak during late summer, in particular due to improved levels of Vit D.
However, indoor athletes such as basketball and gymnasts who may have low level of Vit D and face a risk of injury like stress fractures or muscular pain should also train under the sun.
Vit D supplements in form of tablets or powder help improve Vit D levels however, sunlight is still the best source.!
So next time you feel tired and need that extra push to do something -Go Get the Sun.
1. McCarty MF. Poor vitamin D status may contribute to high risk for insulin resistance, obesity, and cardiovascular disease in Asian Indians. Medical Hypotheses 2009; 72:647-651.
2. Ritu G and Gupta A. Vitamin D deficiency in India: Prevalence, Causalities and Interventions. Nutrients 2014; 6:729-775.
3. Holick MF. Vitamin D deficiency. N Engl J Med 2007; 357: 266-281.
4. Shuler FD et al., Sports health benefits of Vitamin D. Sports Health 2012; 4:496-501.
5. Cannell JJ et al., Athletic performance and Vitamin D. Med Sci Sports Exerci. 2009; 41-1102-1110