Vitamin D is vital for calcium absorption in bones and to improve muscle strength. Not getting enough vitamin D in childhood can slow growth or cause misshapen bones (rickets), and not getting enough vitamin D throughout life increases the risk for bone thinning (osteoporosis) in later years.
Many people can get the amount of vitamin D needed each day by eating a variety of dairy products. Vitamin D is in foods such as egg yolks, liver, saltwater fish, and vitamin D-fortified dairy products. Vitamin D also is available in supplements, often in combination with calcium. People who live in sunny climates can get enough vitamin D through 10 to 15 minutes a day of sun exposure a few days a week.
Most doctors suggest:
WebMD Medical Reference from Healthwise