It may sound ironic that people in a sun-drenched country like India need to be medically prescribed a dose of sunshine for their physical and mental wellness. But, well, that’s the reality of our time.
Deficiency of vitamin D — the ‘sunshine vitamin’ — has indeed emerged as a major public health concern these days. National studies across all age groups and risk categories estimate that deficiency levels range between 40 and 99 per cent.
Most studies show a prevalence between 80 and 90 per cent, according to the Journal of Family Medicine and Primary Care (JFMPC). It’s a silent epidemic, experts underscore.
Some term it a pandemic. In fact, during the Covid crisis when people were forced to remain indoors, several reports termed vitamin D deficiency as “pandemic within a pandemic”. This subsequently drew wider attention to the growing health concern.
Vitamin D plays a vital role in shaping bone and muscle health, and also influencing one’s moods. Global studies conducted after the pandemic have spotlighted its wider importance: in combating cancers, reducing the risk of flu and rheumatoid arthritis, and even offering protection in cases of multiple sclerosis.
One major issue is that vitamin D deficiency is a stealthy disorder, which can go undiagnosed unless timely tests are done. Take college student Aishwarya Kannan’s case. She knew little about the magic of vitamin D — especially the critical component called D3 — when she found herself unable to keep up with the rigours of NEET coaching.
“All my work and attitude seemed to be falling apart. I felt drained, and drowsiness kept me from giving my best to the preparations. I blamed myself initially for not being serious,” she says.
“That was when our course coordinator asked us to get our blood tests done, just to check if we were in good health. The test report revealed that my D3 count was low, just about 20 ng/mL when it should be between 30 to 50 ng/mL.”
This is not an isolated case, but a general pattern rather. Doctors note vitamin D deficiency as a probable underlying reason for symptoms such as fatigue, muscle weakness, brittle bones, mood fluctuations, low immunity, hair loss, and in severe cases, rickets leading to bone deformities.
They also highlight a lack of systematic research on the topic, though independent studies have recently begun highlighting the concern. One such study was conducted in 2025 at a private clinic in Ernakulam, examining the link between depression and D3 deficiency.
The study, published in the JFMPC, found that depression was more prevalent among those with lower D3 levels (67 per cent) than among those with optimum levels. Older adults were at higher risk, and men were found to have 2.9 times the odds of developing depression compared with women if D3-deficient.
Another study, published in the International Journal of Contemporary Paediatrics, notes that satisfactory vitamin D levels were found in only 8.62 per cent of the school children surveyed in central Kerala. The sample group, aged 5 to 13 years, clearly presents a worrying trend — children potentially at risk of developing lifestyle-related disorders.
Experts point to changed lifestyles — especially the indoor-heavy routines — as the main cause for the rising deficiency. “It’s simple: insufficient exposure to healthy sunrays,” says Dr Sheeja Chandran, professor and HoD (Agadatantra) at Pankajakasthuri Medical College.
“Earlier generations had greater exposure to sunlight, the prime source of the vitamin. We used to walk more, do outdoor chores, and encourage children to play outside. Moreover, there was no fear of sun exposure due to cosmetic concerns. All this helped our skin synthesise D3 naturally.”
Dr Sheeja highlights that the benefits of absorbing sunlight is part of ancient wisdom. “Take surya namaskar, for instance. It is an exercise that allows exposure of the body to early sunlight — the ideal time would be from sunrise to about 9am.”
The role of food in supplementing Vitamin D3 remains a subject of debate. While some experts believe a good diet can make a difference, others assert that dietary sources have minimal impact on D3 levels.
Supplements, then, become the easy alternative, says Dr Lisha C, assistant surgeon at Community Health Centre, Puthenthope, Thiru-vananthapuram.
“Rural markers are better than urban ones. The disorder can be corrected if one’s routine is realigned. But changed priorities make such shifts difficult,” she says.
Echoing the observation, Dr Padmakumar calls for more studies on vitamin D3 deficiency in Kerala. “It is an evolving area of concern. We need a comprehensive study to understand both the short- and long-term implications, explore alternative sources, and formulate countermeasures,” he says.
Such research could inform policy-level changes — like making outdoor activities mandatory in school curricula — and drive attitudinal shifts that rekindle a fondness for the sun and its warm, healing rays on flaky Kerala mornings.
Vital checklist
Common symptoms:
Fatigue, pain in bones and muscles, mood changes, recurrent illnesses, slow healing of wounds, hair loss, and skin issues.
Severe symptoms:
Rickets, slow growth, delayed walking (in children), osteomalacia, risk of fracture, muscle spasms and fatigue, cardiac issues, and extreme depressive tendencies.
Remedies
Exposure to sunlight in the early hours (ideally from sunrise to 9am) for at least 20 minutes daily
Healthy diet
Supplements (as advised by the doctor)
What is D3?
It is a subgroup of vitamin D that is produced when sunlight hits the skin. A fat-soluble vitamin, it is minimally found in food.
The process
Sunlight on the skin triggers interaction with 7-dehydrocholesterol, a cholesterol derivative, to form vitamin D3. The liver then converts the D3 into calcidiol, which kidneys transform into calcitriol, an active form of vitamin D.