By Denise Lodge
Are You Vitamin D Deficient?
It is estimated that up to two-thirds of Canadians and one-quarter of Americans are deficient in vitamin D. Some symptoms include loss of appetite and weight, difficulty sleeping, and diarrhea. Deficiencies in vitamin D may increase the risk of breast and colon cancers.
Benefits of Vitamin D
Vitamin D regulates calcium and phosphorus absorption, and is essential for strong teeth and bones. It also assists the immune system by helping to produce white blood cells, which fight infections. Dr. Kathy Fields, co-Founder of Rodan + Fields Dermatologists and Proactiv® Solution, explains that vitamin D “maintains bone density in adults, may inhibit certain cancers such as non-Hodgkin’s lymphoma, and possibly lessens the risk of diseases such as multiple sclerosis.”
Sources of Vitamin D
Sunlight converts 7-dehydrocholesterol, a chemical in the skin, to vitamin D. Once it has been converted, it is processed in the liver and kidneys, where it can be stored for future use.
While sunlight is a well-known source of vitamin D, many dermatologists recommend obtaining vitamin D elsewhere because sunlight’s benefits cannot be separated from an increased risk of skin cancer. Vitamin D can be found in some foods naturally, in fortified foods, and in supplements.
Vitamin D Supplements
For individuals up to 70 years old the recommended dietary allowance (RDA) for vitamin D is 600 International Units (IU), and for those over age 70, it is 800 IU. Adults should not exceed a daily dosage of 4000 IU, as toxicity can result.
For those over age 65, taking vitamin D with calcium every day can significantly reduce age-related fractures. Taking vitamin D with calcium also prevents and treats osteoporosis (the result of depleted calcium), and osteomalacia (the softening of the bones). Vitamin D supplements may also reverse hearing loss caused by deficiency.
Vitamin D Rich Foods
Vitamin D is also found naturally in some foods and is added to some products. A study published in the American Journal of Clinic Nutrition recommends oily fish, such as salmon (360 IU per 3.5-ounce serving), mackerel, and sardines. Egg yolks contain vitamin D, although usually no more than 50 IU per yolk.
Awareness of deficiency during the 1930s led dairy farmers to begin adding vitamin D to their milk. Today, some fortified foods include milk (100 IU per 8-ounce serving), orange juice (100 IU per 8-ounce serving), breakfast cereals, and breads.
Adequate levels of vitamin D are an important part of your daily diet. Be sure to consult your doctor if you suspect you are deficient before taking any new supplements.
About The Author: Denise Lodge has a Bachelor of Arts, Honours degree in Professional Writing. She enjoys reading, writing, and travelling.