Vitamin D

The primer

Despite year-round sun, vitamin D deficiency is remarkably common in the UAE and wider Gulf. Multiple published studies place deficiency rates well above 50% across many demographic groups. The reasons are practical: high temperatures push most outdoor time to early morning or evening (when UVB is weakest), indoor lifestyles, and modest clothing all reduce cutaneous synthesis. Vitamin D contributes to normal calcium absorption, bone health, muscle function and immune function. D3 (cholecalciferol) is the form your skin makes and is significantly better at raising blood levels than D2 (ergocalciferol). Because vitamin D is fat-soluble, take it with a meal containing fat — softgels in oil are ideal, tablets are fine but slightly less bioavailable. The 'right' dose depends on your blood level (measured as 25-hydroxyvitamin D). For most adults, 1000–2000 IU daily is a safe maintenance range; higher doses may be needed to correct deficiency and should be guided by a blood test. Do not self-dose 5000+ IU indefinitely without measurement.