KARACHI: Abundant sunshine has not protected Pakistan from a widespread vitamin D problem. Research discussed at a medical summit in Karachi has highlighted striking levels of deficiency and insufficiency, prompting experts to call for greater public awareness, more careful clinical assessment and safer treatment practices.
The findings also carry an important warning for the public: taking vitamin D supplements without appropriate medical advice is not a substitute for diagnosis, and repeatedly using high doses can be harmful.
At the Connect Summit, organised by Scotmann Pharmaceuticals in Karachi, health experts examined the reported burden of vitamin D deficiency, its possible contributing factors and the importance of managing it across different stages of life. Their message was twofold: vitamin D deficiency deserves attention, but it must be addressed through evidence-based care rather than indiscriminate testing and supplementation.
Research points to a substantial vitamin D burden
In a presentation titled “Mapping the Burden, Mastering the Management,” Dr Sellal Ahmed, Associate Professor at Karachi Institute of Medical Sciences (KIMS) and Consultant at Tabba Heart Institute, reviewed research findings and prescribing guidelines.
A review of 18 publications reported that 84.82 per cent of the people included had vitamin D deficiency or insufficiency. An audit of 60,937 laboratory records found a corresponding rate of 61.1 per cent.
These figures are concerning, but they should not be mistaken for a definitive estimate of vitamin D deficiency across Pakistan. Experts at the summit cautioned that the studies involved different populations and diagnostic thresholds, making direct comparisons difficult and limiting the extent to which the findings can represent the entire country.
The distinction matters. A review of selected studies and an audit of laboratory records can indicate a substantial health concern, but neither automatically provides a nationally representative picture. Laboratory records, in particular, reflect people who underwent testing rather than a random sample of the population.
Independent published research has also documented a high burden. A systematic review and meta-analysis published in BMC Public Health examined 65 studies involving 44,717 participants across five South Asian countries. It estimated the pooled prevalence of vitamin D deficiency among Pakistani adults at 73 per cent, with a 95 per cent confidence interval of 63 to 83 per cent.
However, the researchers reported considerable variation between studies. The Pakistan estimate was based on 18 studies involving 4,354 participants, with a high degree of statistical heterogeneity. This means the findings support concern about the scale of the problem, but should not be read as a precise measurement of current prevalence in every Pakistani community.
Why can vitamin D deficiency occur in a sunny country?
Pakistan's climate might suggest that vitamin D deficiency should be uncommon. Yet sunshine alone does not guarantee that the body produces or receives enough of the vitamin.
Experts at the Karachi summit identified limited sunlight exposure, indoor lifestyles, covered clothing, air pollution and dietary deficiencies among the factors that may contribute to low vitamin D levels.
Vitamin D is produced in the skin following exposure to ultraviolet B (UVB) radiation. The amount produced can vary with the time spent outdoors, clothing, skin pigmentation, age, season, location and other factors. Air pollution and lifestyle patterns may also influence how much effective sunlight reaches people.
Diet can be another source, although relatively few foods naturally contain substantial amounts of vitamin D. Fatty fish, egg yolks and certain fortified foods can contribute to intake, while dietary patterns that offer few such sources may increase the risk of inadequate levels.
The result is a public-health challenge that cannot be explained simply by whether a country receives sunshine. Everyday habits, environmental conditions, nutritional intake and individual health circumstances all matter.
Experts caution against unnecessary testing, megadose supplements
One of the summit's most important messages concerned how vitamin D deficiency should be diagnosed and treated.
Dr Ahmed recommended targeted testing for people with relevant clinical indications, including skeletal disease and conditions associated with malabsorption, rather than routine screening of all healthy adults.
He also emphasised individualised supplementation, appropriate monitoring and avoiding repeated megadoses without reassessment.
This advice is important because vitamin D supplements are widely available and are sometimes taken without a confirmed deficiency or a clear treatment plan. A high dose is not automatically more effective, and repeated supplementation without medical supervision can expose people to avoidable harm.
The US National Institutes of Health Office of Dietary Supplements notes that excessive vitamin D intake can cause toxicity, leading to elevated calcium levels in the blood and urine. Severe cases can result in kidney problems, soft-tissue calcification and abnormal heart rhythms. The risk is particularly relevant when people take excessive amounts of supplements over time.
International guidance also distinguishes between testing people who have clinical reasons for assessment and screening otherwise healthy individuals. The US Preventive Services Task Force has found insufficient evidence to determine the balance of benefits and harms of routine screening for vitamin D deficiency in asymptomatic adults.
These recommendations do not mean that vitamin D deficiency should be ignored. Rather, they underline the need to identify people who may benefit from assessment and treatment, while avoiding unnecessary investigations and unsupervised supplementation.
Bone health depends on attention from childhood
The importance of vitamin D extends across the life course, particularly because of its role in calcium absorption and the maintenance of healthy bones.
Dr Pervez Ali, Associate Professor of Orthopaedics at Jinnah Postgraduate Medical Centre (JPMC), addressed this subject in a presentation titled “From Childhood to Aging — Vitamin D, a Lifetime Partner in Bone Health.”
He cited research indicating that approximately 73 per cent of Pakistani adults have insufficient vitamin D despite the country's abundant sunshine.
Dr Ali also highlighted that nearly 90 per cent of peak bone mass is acquired by the end of adolescence. This makes childhood and teenage years important periods for supporting healthy bone development through adequate nutrition, physical activity and appropriate attention to vitamin D status.
Poor bone health can have consequences later in life. Inadequate mineralisation during growth may contribute to skeletal problems, while bone loss with ageing can increase vulnerability to fractures. Vitamin D is one part of this wider picture, alongside calcium intake, physical activity, hormonal factors and other aspects of health.
The message from the summit was that bone health should not become a concern only in older age. Preventive attention during childhood, adolescence and adulthood can help support skeletal health throughout life.
Vitamin D and women's health across different life stages
The discussion also considered vitamin D in relation to women's reproductive and post-menopausal health.
Dr Farzana Amir outlined potential associations between vitamin D status and menstrual disorders, polycystic ovary syndrome (PCOS), insulin resistance and infertility. She also discussed possible links with pregnancy complications, including gestational diabetes and preeclampsia.
These are important areas of clinical and scientific interest, but associations should not be interpreted as proof that vitamin D deficiency directly causes these conditions. Their development is complex and may involve multiple biological, hormonal, metabolic and environmental factors.
Dr Amir also highlighted concerns about bone loss, muscle weakness and increased fracture risk after menopause. As women age and experience changes in hormonal levels, maintaining skeletal health becomes increasingly important. Vitamin D assessment and supplementation may form part of care where clinically indicated, alongside other preventive and treatment measures.
The discussion reinforced the need to consider individual health circumstances rather than treating vitamin D as a single explanation or solution for a wide range of conditions.
Medical experts call for evidence-based vitamin D management
Other speakers at the Karachi summit included Dr Fakhra Sanjrani, Dr Yousuf Kamal, Dr Jagdesh Kumar, Prof. Dr Ahmed Iqbal Mirza and Dr Avenash Punshi.
The programme brought together medical perspectives on vitamin D deficiency, bone health, women's health and appropriate clinical management. The central message was that awareness must be accompanied by responsible diagnosis and treatment.
For the public, this means avoiding two common mistakes: overlooking symptoms or medical conditions that may warrant assessment, and assuming that taking large doses of vitamin D without guidance is harmless.
People with concerns about bone health, suspected nutritional deficiencies, malabsorption or other relevant medical conditions should discuss appropriate assessment with a qualified healthcare professional. Anyone already taking high-dose supplements should seek advice on whether the dose and duration remain appropriate.
Pakistan's reported vitamin D burden deserves serious attention from healthcare professionals, researchers and public-health authorities. Better evidence, improved nutritional awareness and appropriate clinical care can help address the problem without encouraging unnecessary testing or unsafe self-medication.
The takeaway from the Karachi summit is clear: vitamin D deficiency should not be dismissed because Pakistan is a sunny country, but neither should supplements be treated as harmless shortcuts to better health.
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