The wisdom of tradition.
Proven by science.

Ayurveda does prescribe morning sun. Atapa sevana, deliberate sunbathing, sits in the daily routine as a practice for strength and vitality, and it is old enough to predate any way of explaining why it might work. But the system has no notion of a vitamin, no notion of a deficiency disease, and it never connects sunlight to bones that bend. The overlap with the claim above is a coincidence of practice rather than support for it: the habit is real, the reasoning behind it is unrelated, and nobody has put the Ayurvedic version up against rickets or osteomalacia in a trial. Getting the right instruction for the wrong reason is still worth recording — but it is not the same as knowing.

What the science saysModern research confirms that vitamin D deficiency is widespread and directly causes nutritional rickets in children and osteomalacia in adults, by impairing calcium absorption and bone mineralisation. Breastfed infants are a specific at-risk group, because breast milk is naturally low in vitamin D.