Vitamin D is a fat-soluble vitamin that is naturally presented from sun exposure, supplements, and very few foods.
These Selected Food Sources include Vitamin D:
- Cod liver oil
- Salmon (sockeye)
- Tuna fish
- Orange juice fortified with vitamin D
- Egg (vitamin D is found in yolk)
- Swiss Cheese
Vitamin D is obtained from sun exposure, food, and supplements is biologically inert and must undergo two hydroxylations in the body for activation. The breakdown of Vitamin D first occurs in the liver and converts to 25-hydroxyvitamin D [25(OH)D], also known as calcidiol. The second occurs primarily in the kidney and forms the physiologically active 1,25-dihydroxy vitamin D [1,25(OH)2D], also known as calcitriol. 1
Vitamin D is a fat-soluble vitamin is stored in the body’s fatty tissue.
Too much vitamin D can cause the intestines to absorb too much calcium. High levels of calcium in the blood may lead to:
- Calcium deposits in soft tissues such as the heart and lungs
- Confusion and disorientation
- Damage to the kidneys
- Kidney stones
- Poor appetite
- Weight loss
To follow is the age recommendation of Vitamin D level that the National Health Institute recommends:
- 0 – 6 months: 400 IU (10 micrograms (mcg) per day)
- 7 – 12 months: 400 IU (10 mcg/day)
- 1 – 3 years: 600 IU (15 mcg/day)
- 4 – 8 years: 600 IU (15 mcg/day)
- 9 – 70 years: 600 IU (15 mcg/day)
- Adults over 70 years: 800 IU (20 mcg/day)
- Pregnancy and breast-feeding: 600 IU (15 mcg/day)
Vitamin D toxicity almost always occurs from the use of too much Vitamin D supplements.
Guidelines from the Institute of Medicine increased the recommended dietary allowance (RDA) of vitamin D to 600 international units (IU) for everyone ages 1-70 and raised it to 800 IU for adults older than age 70 to optimize bone health. The safe upper limit was also raised to 4,000 IUs. The safe upper limit for vitamin D is:
- 1,000 to 1,500 IU/day for infants
- 2,500 to 3,000 IU/day for children 1 -8 years
- 4,000 IU/day for children 9 years and older, adults, and pregnant and breast-feeding teens and women. 2
A blood lab test can indicate whether you have enough Vitamin D in your body. 3
Researchers continue to discover the additional benefits of Vitamin D.
Resources: 1. http://ods.od.nih.gov/factsheets/VitaminD-HealthProfessional/ 2.http://www.nlm.nih.gov/medlineplus/ency/article/002405.htm 3.http://www.webmd.com/food-recipes/vitamin-d-deficiency?page=2