Vitamin D deficiency is a global health problem currently. More than 1 billion people worldwide are estimated to have inadequate levels of vitamin D. The dosage of vitamin D is purely based on your age and lifestyle. The recommended daily allowance of Vitamin D is about 400-600IU. If there is an acute deficiency, we may have to intake 3 to 4x more than this until we maintain the levels at an optimum. Vitamin D deficiency can result in a series of problems affecting every single system in our body and can put the body through a phase of compromised immunity.