Vitamin D deficiency has been linked to increase the risk for many common and serious health issues. Low vitamin D levels can lead to osteoporosis and increase your risk of falls and fractures if you are over the age of 50. Osteoporosis occurs when your bones lose calcium and other minerals, making them fragile and more likely to break. Adequate levels of vitamin D help your body to absorb calcium, while not having enough can increase your risk of developing osteoporosis.People with very low levels of vitamin D (moderate to severe deficiency) are the most at risk of developing health problems. Studies suggest that exposure to sunlight which enhances the production of vitamin D in the skin may prevent many chronic diseases.