This is because worldwide a huge chunk of the population is deficient in vitamin D. As per a 2021 report, close to 1 billion people worldwide are affected by vitamin D deficiency and half of these people have vitamin D insufficiency.
With such a huge number of people already deficient in one of the essential vitamins required for the brain, people must get their vitamin D levels checked up regularly. Instead of solely relying on supplements people should get sun exposure so that the vitamin is naturally produced in the body.
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