Are we running away from UV rays?

01 February 2014 | Column | By Narayan Kulkarni

Majority of Indians live in tropical region, receiving ample sunlight (ultra violet rays) throughout the year and hence there was disbelief that Vitamin D deficiency is common
in India. However, the data available shows that nearly 60-90% people are deficient. This is so alarming to witness with so much of sunshine...
Make hay while the sun shines has been an oft used idiom. It conveys the need to take advantage of opportunities that come one’s way. India, which has plenty of sunshine, would natrually like to make full use of this god given gift. There is disbelief that Vitamin D deficiency is uncommon in India. However, available data shows otherwise.

The Indian Council of Medical Research (ICMR) has called for an expression of interest for participation in task force on Vitamin D, which it wants to constitute, to review the existing information available on prevalence of Vitamin D deficiency and plan for mapping of this micronutrient deficiency and other required studies.

Hailing the decision of ICMR, Dr B Sesikeran, former Director, National Institute of Nutrition, Hyderabad, said, “It is extremely relevant and appropriate that ICMR has decided to set up a task force on Vitamin D. There are several issues which still remain unanswered such as; what are the normal range of values for serum 25 Hydroxy Vitamin D among those adequately exposed to the appropriate quantity and quality of sunlight in the different latitude in our country; what is the actual extent of deficiency and what are the age specific prevalences of Vitamin D deficiency; and to what extent does such a deficiency impact pregnancy, lactation, fetal growth, birth weight, incidence of diabetes and other chronic diseases, osteoporosis, stunting and many other public health issues existing now.”

Supporting the views of Dr B Sesikeran, Salome Benjamin, a medical nutritionist attached to Topiwala National Medical College Nair Hospital, Mumbai, said, “This is indeed a very good initiative by ICMR. In 2013, I must have seen daily one or two patients with Vitamin D deficiency. To my surprise one government school for physically challenged has over 80% of children with Vitamin D deficiency.”

Benjamin, a consultant to endocrine services with daily OPD, said they called for a parents/teachers meet for advice to bring awareness about importance of Vitamin D.

Echoing similar thoughts Dr Dharini Krishnan, Consultant Dietitian from Chennai and former National President of Indian Dietetic Association (IDA) said, “I think it is a great step forward and all stakeholders should be involved”.

By setting up a task force, the ICMR, intends to assess the existing research methodologies for assessment of Vitamin D deficiency and make recommendations for appropriate research methodologies for this micronutrient. The task force hopes to develop innovative approaches for awareness of population with respect to significance of adequate intake of Vitamin D and to develop research facilities for assessment of Vitamin D problem and developing capacity building of scientists in carrying out this micronutrient research.

“A task force setup by ICMR has immense relevance in the present scenario and would contribute significantly towards generating Indian data on prevalence of Vitamin D deficiency at various levels across age groups with special reference to women and children,” said Dr Jagmeet Madan, President, Indian Dietetic Association (Mumbai Chapter).

She further said “It should come out with practical recommendations to sensitise population at large about significance of good diet, sunshine exposure and physical activity for its prevention. It also needs to deliberate the cost effective methodologies for Vitamin D levels estimation for people at large. We need to address the question “Is Vitamin D supplementation for life true in an urban environment? What are the dosages, preferred mode and duration for different age groups”.

Vitamin D deficiency is rampant in India with majority of the population showing subclinical deficient levels of serum Vitamin D levels. “There are many intriguing questions which remain unanswered for Indian population which are beyond the factors responsible for decreased sunshine exposure of population in a tropical country.”

“The significance of low subclinical levels cut across all age groups, with subclinical Vitamin D deficiency having a broad spectrum of physiological consequences, manifesting in increased predisposition to a host of non-communicable diseases including diabetes, musculoskeletal and bone disorders in face of stark sarcopenia in Indian population,” added Dr Jagmeet Madan. She has already given her inputs as a member of research sub-committee to the Nutrition Research Priority Setting in ICMR - International Clinical Epidemiology Network.

According to a review article titled ‘Vitamin D, arterial hypertension & cerebrovascular disease’ covered in The Indian Journal of Medical Research, one of the oldest medical journals and official publication of ICMR in April 2013 issue, Vitamin D is currently of great public health interest, because Vitamin D deficiency is common and is causally associated with musculoskeletal diseases.

Vitamin D supplementation is therefore, in many countries, recommended to prevent rickets in children and is also a standard treatment for patients with osteoporosis because Vitamin D supplementation reduces fractures and falls. These skeletal effects of Vitamin D are closely related to the role of Vitamin D in regulating bone and mineral metabolism, by ensuring physiologic calcium absorption in the gut and thus providing sufficient calcium for bone mineralisation. In addition, there has been an increasing interest over the last few years in the relationship of Vitamin D with extra-skeletal diseases. This increased interest was caused by the identification of Vitamin D receptors (VDRs) in almost all human cells. Several epidemiological studies have shown associations of Vitamin D deficiency with a variety of chronic extra-skeletal diseases, including cardiovascular and renal diseases, cancer, autoimmune, neurological and infectious diseases.

Experimental studies support the notion that Vitamin D exerts anti-hypertensive effects and has a beneficial impact on the overall cerebrovascular risk profile and on stroke outcome. Some small randomised controlled trials (RCTs) have already shown a modest blood pressure reduction by Vitamin D treatment, but this has not been consistently observed in all studies.

The findings of the large systematic review, published in The Lancet Diabetes & Endocrinology, challenge the prevailing wisdom among many scientists that Vitamin D has a potential role in disease prevention and will have important implications for nearly half of US adults who take Vitamin D supplements at an overall cost of $600 million every year.

“We come across more and more problems related to bones among middle aged men and women. As nutritionists and medical personnel we need to explore the causes, remedies of required lifestyle modification,” says Dr S Premakumari, Editor, The Indian Journal of Nutrition and Dietetics and a dean at the Avinashilingam Deemed University for Women, Coimbatore. Appreciating ICMR’s effort, she is ready to serve on this task force.

Finding the truth
The formation of a task force will help to find out the most important treatment protocol which needs to be defined. Dr Sesikeran noted that at the moment physicians seem to treat Vitamin D deficiency based on the pharma industry’s guidance, which may or may not be right. Some prescribe 60,000 IU every week, some give the same once a month, once in two months, 1000 IU every day and so on. In our population, what are the safe upper limits we need to identify. He feels there are other issues, which still remain unanswered, such as

* What happens if we give lots of Vitamin D without adequate calcium intakes, which is not a problem in the West;
* Should we define our RDA for Vitamin D from 400 IU to higher levels;
* Single nutrient supplementations have been largely ineffective, should Vitamin D also be part of a package of fortificants.

“In fact Vitamin D research has turned out to be an exciting field of research since there are more gaps than facts available with us now,” concludes Dr Sesikeran.


Causes of Deficiency

- Changing food habits
- Strict vegetarian habits
- Increasing number of hours spent indoors
- Increased air pollution hampering the ultraviolet rays to adequately synthesize Vitamin D in the skin
- Travelling in cars rather than open vehicles like cycles/scooters/bikes etc.
- Tanning prevention of one’s skin in sunlight to have good fair looks
- Highly competitive and busy study schedules in schools and homes for the kids with negligible emphasis on physical activities in open grounds, in sunlight, in the schools coupled with least hrs of kid’s play outdoors even at homes
- Cultural and traditional habits prevalent in certain religions like “burqa” and the “pardah” system in muslims, have all contributed to this present dismal scenario|

Source: http://yadavpathlabbhiwani.blogspot.in



Vitamin D and its types:

Vitamin D is found in few dietary sources. Sunlight exposure is the primary source of vitamin D for majority of people, other than supplements. In some countries, staple foods are artificially fortified with vitamin D.


Vitamin D2
- Mushrooms, portabella, exposed to ultraviolet light, raw: Vitamin D2: 11.2 μg (446 IU)
- Mushrooms, portabella, exposed to ultraviolet light, grilled: Vitamin D2: 13.1 μg (524 IU) Mushrooms, shiitake, dried: Vitamin D2: 3.9 μg (154 IU)
- Mushrooms, shiitake, raw: Vitamin D2: 0.4 μg (18 IU)
- Mushrooms, portabella, raw: Vitamin D2: 0.3 μg (10 IU)
- Mushroom powder, any species, illuminated with sunlight or artificial ultraviolet light sources
- Alfalfa (Medicago sativa subsp. sativa), shoot: 4.8 μg (192 IU) vitamin D2, 0.1 μg (4 IU) vitamin D3 (per 100 g).


Vitamin D3
Vegan sources - Lichen
Cladina arbuscula specimens grown under different natural conditions: The contents of vitamin D3 range from 0.67 to 2.04 μg g–¹ dry matter in the thalli of C. arbuscula specimens grown under different natural conditions.


Animal sources
Fish liver oils, such as cod liver oil, 1 Tablespoon (15 ml) provides 1,360 IU (90.6 IU/ml)

Fatty fish species, such as:
Catfish (wild), 85 g (3 oz) provides 425 IU (5 IU/g)
Salmon, cooked, 100 g (3.5 oz) provides 360 IU (3.6 IU/g)
Mackerel, cooked, 100 g, 345 IU (3.45 IU/g)
Sardines, canned in oil, drained, 50 g (1.75 oz), 250 IU (5 IU/g)
Tuna, canned in oil, 100 g, 235 IU (2.35 IU/g)
Eel, cooked, 100 g, 200 IU (2.00 IU/g)

A whole egg provides 20 IU if egg weighs 60 g (0.333 IU/g)
Beef liver, cooked, 100 g, provides 15 IU (0.15 IU/g)

Industrial production:
Vitamin D3 (cholecalciferol) is produced industrially by exposing 7-dehydrocholesterol to UVB light, followed by purification.] The 7-dehydrocholesterol is a natural substance in wool grease (lanolin) from sheep or other woolly animals. Vitamin D2 (ergocalciferol) is produced in a similar way using ergosterol from yeast or mushrooms as a starting
material.




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