There have been considerable discussions in scientific circles on the importance of vitamin D in these days of the COVID-19 pandemic. Maryam Edabi and Aldo Montana-Loza have published a paper titled, “Perspective: Improving vitamin D status in the management of COVID-19,” in European Journal of Clinical Nutrition (2020) 74:856-859; https://doi.org/10.1038/s41430-0200661, which points out how vitamin D deficiency can affect COVID-19 high-risk patients, particularly those who are diabetic, have heart conditions, pneumonia, obesity and those who smoke. It is also associated with infections in the respiratory tract and lung injury.

Besides, vitamin D is known to help in having the right amount of calcium in the bones, catalyse the process of protecting cell membranes from damage, preventing the inflammation of tissues and helping stop tissues from forming fibres and weakening bones from becoming brittle, leading to osteoporosis. Thus, the levels of vitamin D (and calcium) in human (and animal) bodies need to be monitored and when necessary, and administered in appropriate doses and frequency, externally by a trained clinician.

Vitamin D and its prevalence

The easy to read site <ods.od.nih.gov> describes vitamin D in detail. It is produced when sunlight (or artificial light, particularly in the ultraviolet region of 190-400 nm wavelength) falls on the skin and triggers a chemical reaction to a cholesterol-based molecule, and converts it into calcidiol (adding one hydroxyl group, also called 25(OH)D technically) in the liver and into calcitriol (or 1, 25(OH)2D) in the kidney. It is these two molecules that are physiologically active. It is suggested that the level of 25-OHD in the range 30-100 ng/ml is thought to be sufficient for a healthy body; levels between 21-29 ng/ml are considered insufficient, and levels below 20 ng/ml mean the individual is deficient in the vitamin.

Since sunlight in important for the generation of vitamin D, tropical countries have an advantage over the northern countries. India, being a tropical country, one would expect naturally derived vitamin D levels to be good. Yet, it is not so!

Indeed a paper by Sandhiya Selvarajan and colleagues, titled, “Systematic review on vitamin D level in apparently healthy Indian population and analysis of its associated factors” was published in September 2017, in Indian Journal of Endocrinology and Metabolism, 2017; 21(5):765-775, free access directly or through http://www.ijem.in/text.asp?2017/21/5/7652/21/5/765/214773. The group did a thorough and exhaustive analysis of over 2,998 published papers and reports, and also data from studies done in various states of India (North Zone, comprising Jammu and Kashmir, Himachal Pradesh, Punjab, Uttarakhand, Uttar Pradesh and Haryana; East Zone: Bihar, Odisha, Jharkhand and West Bengal; West Zone: Rajasthan, Gujarat, Goa and Maharashtra; South Zone: Andhra Pradesh, Telangana, Karnataka, Kerala and Tamilnadu and the Northeast Zone: Assam, Sikkim, Nagaland, Meghalaya, Manipur, Mizoram, Tripura and Arunachal Pradesh). Overall, these 40 studies provided a sample of 19,761 persons. The level of vitamin D from all these 40 studies ranged between 3.15 ng/ml to 52.9 ng/ml. Vitamin D level among south Indians is (15.74–19.16) ng/ml, yet below 20. Also, females showed consistently lower levels than males.

The authors conclude that India, a nation of abundant sunshine, is surprisingly found to have a massive burden of vitamin D deficiency among the public irrespective of their location (urban or rural), age or gender, or whether they are poor or even rich. Hence, it is clear that vitamin D supplementation is necessary for most Indians to treat its deficiency.

Nutritive food

The Central and State governments, as well as public-spirited foundations, companies and even sympathetic public have been very helpful in offering free food for crores of poor, particularly, migrant workers. In addition,almost all of them are extremely poor and have had to depend on such food. Their vitamin D levels must certainly be less (far less) than 10 ng/ml. Typically, these food supplies have included wheat or rice, and grains (chana, urad and the like), and some highly subsidised items of food (sugar, milk and such). Vegetables are not given — raw or cooked — though cooked meals are offered in cities and towns by the State governments and private foundations, at affordable prices. Also, the main government schemes of giving free mid-day meal scheme for students studying in government schools, and the feeding programmes for preschool children and pregnant women under the Integrated Child Development Services through angadwadis have been vital.

Given the deficit in vitamin D (indeed in many other vitamins, and calcium), it is highly desirable for the governments to (a) consult nutrition experts and institutions to advise and suggest the type of nutritive items that can be added to the current ‘ration’ food given to the poor, and the meals given to school children, (b) in any case, supply free of charge, vitamin D, other vitamins and calcium, in consultation with medical and public health experts regarding the dosage, frequency and other details. There are excellent Indian companies that manufacture these. With these steps, India will have armed its poor against not just the current, but future pandemics as well.

(I thank Drs. Mahtab Bamji and Ghanshyam Swarup, and Shakti Balasubramanian for their inputs and advice.)

dbala@lvpei.org