by Scheinberg D

IMAGE Vitamin D is a fat-soluble vitamin. These types of vitamins are stored in the body's liver and fatty tissues.

Vitamin D acts as both a vitamin and a hormone. It is found in some foods, but the main sources are vitamin D-fortified milk and sunlight.


Vitamin D plays a role in the growth and maintenance of strong, healthy bones. It also helps to maintain normal blood levels of calcium and phosphorus.

As a supplement, it may help treat osteoporosis and high blood pressure.

Recommended Intake

Here are the guidelines for vitamin D intake:

Age Group Recommended Dietary Allowance or Adequate Intake (IU/Day)
0-12 months 400
1-70 years 600
71+ years 800
Pregnant or nursing women 600

Vitamin D Deficiency

Symptoms of severe vitamin D deficiency are rare today, but can lead to:

  • Rickets—a disease in children in which the bones become soft and weak
  • Osteomalacia—a disease in adults in which the bones become soft and weak
  • Muscle weakness

Mild deficiency is common, especially in places that have less sunlight.

Vitamin D Toxicity

Vitamin D is stored in the body and does not pass out through urine. It can build up and reach toxic levels. Here are safe upper level intakes for vitamin D:

Age Group Upper Level Intake (IU/Day)
0-6 months 1,000
7-12 months 1,500
1-3 years 2,500
4-8 years 3,000
9 years and older 4,000
Pregnant or nursing women 4,000

IU: international units

Symptoms of toxicity are:

  • Nausea
  • Vomiting
  • Constipation
  • Weakness
  • Weight loss
  • Heart rhythm problems
  • Deposits of calcium in soft tissues from raised levels of calcium in the blood

Sunlight and diet are not likely to cause vitamin D toxicity.

Major Food Sources

Fortified foods have the most vitamin D. Examples of foods that may be fortified with vitamin D are:

  • Milk
  • Cereal
  • Orange juice
  • Yogurt
  • Margarine
  • Soy drinks

There are not many foods that are natural sources of vitamin D. They are:

  • Fatty fish, such as salmon, tuna, and mackerel
  • Beef liver
  • Cheese
  • Egg yolks
  • Mushrooms

Health Implications

Vitamin D deficiency is more common in:

  • Breastfed babies who do not get enough vitamin D from human milk. They should get a 400 IU vitamin supplement each day to make up for this.
  • People who live in places with limited sun exposure
  • Older adults who spend a lot of time indoors, such as in care centers or nursing homes
  • People who wear clothing that limits their exposure to the sun
  • Pregnant women
  • Dark-skinned people whose bodies are less able to make vitamin D from the sun
  • People with obesity

Tips to Raise Your Vitamin D Intake

Here are tips to help raise your intake:

  • Make sure your multivitamin contains vitamin D.
  • Drink vitamin D-fortified milk.
  • Spend time in the sun. You should still use sunscreen with an SPF of 30 or higher.


Eat Right—Academy of Nutrition and Dietetics 

Office of Dietary Supplements—National Institutes of Health 


Dietitians of Canada 

Health Canada 


Calcium and vitamin D for treatment and prevention of osteoporosis. EBSCO DynaMed website. Available at: . Updated February 4, 2020. Accessed February 6, 2020.

Vitamin D. Office of Dietary Supplements website. Available at: Updated August 7, 2019. Accessed February 6, 2020.

Vitamin D and skin health. Oregon State University Linus Pauling Institute website. Available at: Accessed February 6, 2020.

Vitamin D intake and supplementation. EBSCO DynaMed website. Available at: . Updated November 26, 2018. Accessed February 6, 2020.

Revision Information