Vitamin D

Vitamin D is a fat-soluble vitamin, and plays a crucial role in the use of calcium in the body. By increasing the absorption of calcium in the body, vitamin D and calcium work together in the formation and maintenance of strong bones and teeth. Also, vitamin D helps the immune system and regulates cell growth.

How much do I need?

  • 600 IU’s (International Units) for people under 50 years
  • 800 IU’s (International Units) for people over 50 years
  • For more recommendations for infants, children, and teens, check out the chart in CSU Extension’s Fact Sheet: Fat-Soluble Vitamins: A, D, E, and K.

Sources of vitamin D

Vitamin D can be found in milk, cheese, and fortified foods such as almond milk, orange juice, soy milk, and mushrooms. Fish such as herring, salmon, and sardines are also high in vitamin D.

In addition to food sources, the body makes vitamin D through our skin when exposed to sunlight. The amount of vitamin D obtained from the sun varies based on location, elevation level, skin color, sunscreen use, cloudiness, and many more factors. Although the sun is important for getting enough vitamin D, make sure to apply sunscreen for any sun exposure past fifteen minutes to reduce the risk of skin cancer.

What happens if I don’t get enough?

In developing children, too little vitamin D can result in rickets (long and soft bowed legs) and flattened back of the skull. Deficiency of vitamin D in adults may cause muscle or bone weakness as well as osteoporosis (loss of bone mass). Individuals with dark skin and the elderly commonly do not get enough vitamin D from sunlight and should do so by other means.

Can I get too much?

Overdose of vitamin D is most common from consuming large amounts of fortified foods. It can cause excess calcium in the blood, slowed growth, smaller appetite, nausea, and vomiting. Children and infants are at a greater risk for consuming too much vitamin D because of their smaller body size.