Health Issues
Vitamin D and Bone Health What is Vitamin D?
Vitamin D is an essential nutrient that helps the body to absorb calcium in order to maintain and protect healthy bones.(1) According to Osteoporosis Canada taking vitamin D3 increases calcium absorption as much as 30-80 percent!(2) Some studies have suggested vitamin D also plays a role in improving muscle strength, reducing fracture rates as well as the rate of falls.(3,4,5)
How does it Work?
Once vitamin D has entered the body it sends out a signal to three areas:
1. It tells the gastrointestinal (GI) tract to absorb calcium
2. The bones to release some stored calcium
3. The signal also tells the kidneys to retain more calcium.
These actions maintain calcium balance in the body and support new bone formation.(6)
Recommended Dosage
Canada’s Food Guide recommends that all Canadians over the age of two consume 500 mL (two cups) of milk every day or fortified beverage which provides 200 IU of vitamin D. In addition to following the Food Guide; everyone over the age of 50 should take a daily supplement of 400 IU of vitamin D.(7)
Osteoporosis Canada new guidelines, July 2010, recommend for daily intake of vitamin D:
Adults under the age of 50 without osteoporosis or conditions affecting Vitamin D absorption require between 400-1000 IU per day.
Adults over the age of 50 require between 800 - 2000 IU per day.(2)
Sources of Vitamin D
Vitamin D comes from three different sources: sunlight, diet, or supplement form.(7)
Sunlight
Vitamin D is an essential nutrient that helps the body to absorb calcium in order to maintain and protect healthy bones.(1) According to Osteoporosis Canada taking vitamin D3 increases calcium absorption as much as 30-80 percent!(2) Some studies have suggested vitamin D also plays a role in improving muscle strength, reducing fracture rates as well as the rate of falls.(3,4,5)
How does it Work?
Once vitamin D has entered the body it sends out a signal to three areas:
1. It tells the gastrointestinal (GI) tract to absorb calcium
2. The bones to release some stored calcium
3. The signal also tells the kidneys to retain more calcium.
These actions maintain calcium balance in the body and support new bone formation.(6)
Recommended Dosage
Canada’s Food Guide recommends that all Canadians over the age of two consume 500 mL (two cups) of milk every day or fortified beverage which provides 200 IU of vitamin D. In addition to following the Food Guide; everyone over the age of 50 should take a daily supplement of 400 IU of vitamin D.(7)
Osteoporosis Canada new guidelines, July 2010, recommend for daily intake of vitamin D:
Adults under the age of 50 without osteoporosis or conditions affecting Vitamin D absorption require between 400-1000 IU per day.
Adults over the age of 50 require between 800 - 2000 IU per day.(2)
Sources of Vitamin D
Vitamin D comes from three different sources: sunlight, diet, or supplement form.(7)
Sunlight
The body can naturally produce vitamin D once it has been exposed to the UVB rays from sunlight.9 Factors to keep in mind which can affect how much vitamin D is produced depend on:
Time of day
Season- Sun rays are not as strong during the winter months (October to March) which can make it difficult for the body to produce vitamin D
Latitude- Depending on your geographical location, it may be difficult to obtain vitamin D from sunlight year round.
Skin Pigmentation- Individuals who have dark pigmented skin have a more difficult time creating vitamin D from sun light, compared to individuals with fair pigmented skin
Age-As we age, our skin has reduced ability to produce vitamin D from sunlight.
Lifestyle Habits- Many people try to protect their skin from the sun by staying indoors, covering up with clothing, or using sunscreen (even a sun protection factor (SPF) of 8 can reduce production of vitamin D by as much as 95 percent).(8, 11)
This means that Canadians must rely on other sources such as diet and supplementation to ensure adequate levels of vitamin D.
Season- Sun rays are not as strong during the winter months (October to March) which can make it difficult for the body to produce vitamin D
Latitude- Depending on your geographical location, it may be difficult to obtain vitamin D from sunlight year round.
Skin Pigmentation- Individuals who have dark pigmented skin have a more difficult time creating vitamin D from sun light, compared to individuals with fair pigmented skin
Age-As we age, our skin has reduced ability to produce vitamin D from sunlight.
Lifestyle Habits- Many people try to protect their skin from the sun by staying indoors, covering up with clothing, or using sunscreen (even a sun protection factor (SPF) of 8 can reduce production of vitamin D by as much as 95 percent).(8, 11)
This means that Canadians must rely on other sources such as diet and supplementation to ensure adequate levels of vitamin D.
Diet
It may be difficult to obtain and maintain adequate amounts of vitamin D from diet alone, since few dietary products contain natural vitamin D.(10)
According to Osteoporosis Canada small amounts of vitamin D can be obtained from dietary sources such as: “eggs, chicken liver, salmon, sardines, herring, mackerel, swordfish, and fish oils (halibut and cod liver oils)”.(2)
Other food sources have vitamin D added to them such as: margarine, goat’s milk, cow’s milk, and plant based beverages (such as soy products).(11, 12) Orange juice may be fortified with calcium, but may not have added vitamin D.(11) Be sure to read the Nutrient Values on the packaging.
Supplement Form
A supplement may be required to meet the individual’s daily intake needs that can not be met through sunlight or diet. According to Health Canada the daily recommended amount is 400 IU per day.(7) The need for vitamin D increases after the age of 50.(11)
A supplemental vitamin D tablet or liquid vitamin D drops are also recommended for individuals that do not receive their calcium requirements from fortified milk or soy beverages.(6,8)
Vitamin D Deficiency
There have been several bone diseases that have been link with having low levels of vitamin D in the body.
Ricketts is a disease that affects children who do not receive enough calcium and vitamin D in their diet. This results in poor calcification and weakness of bones leading to growth abnormalities.
Osteomalacia is the softening of bones seen in women with low calcium diets and minimal sun exposure.
Osteoporosis results from the loss of calcium from the bones and can lead to fractures.(6)
Vitamin D Toxicity
Health Canada recommends that individuals should not exceed 2000 IU of vitamin D per day (including diet and supplements); unless advised by your healthcare provider.(7) Getting vitamin D toxicity is rare; as long as you make healthy lifestyle choices and follow the advice of your healthcare provider.
Things to Keep in Mind
-Vitamin D3 increases calcium absorption as much as 30-80 percent.
-Based on geographical location, it may be difficult to obtain vitamin D from sunlight year round. -Look for foods that have vitamin D added to them to help you meet your daily needs.
Created by Mia Kubrak for The Women’s Midlife Health Program
Nursing Education Program of Saskatchewan
January 2010 updated August 2010
It may be difficult to obtain and maintain adequate amounts of vitamin D from diet alone, since few dietary products contain natural vitamin D.(10)
According to Osteoporosis Canada small amounts of vitamin D can be obtained from dietary sources such as: “eggs, chicken liver, salmon, sardines, herring, mackerel, swordfish, and fish oils (halibut and cod liver oils)”.(2)
Other food sources have vitamin D added to them such as: margarine, goat’s milk, cow’s milk, and plant based beverages (such as soy products).(11, 12) Orange juice may be fortified with calcium, but may not have added vitamin D.(11) Be sure to read the Nutrient Values on the packaging.
Supplement Form
A supplement may be required to meet the individual’s daily intake needs that can not be met through sunlight or diet. According to Health Canada the daily recommended amount is 400 IU per day.(7) The need for vitamin D increases after the age of 50.(11)
A supplemental vitamin D tablet or liquid vitamin D drops are also recommended for individuals that do not receive their calcium requirements from fortified milk or soy beverages.(6,8)
Vitamin D Deficiency
There have been several bone diseases that have been link with having low levels of vitamin D in the body.
Ricketts is a disease that affects children who do not receive enough calcium and vitamin D in their diet. This results in poor calcification and weakness of bones leading to growth abnormalities.
Osteomalacia is the softening of bones seen in women with low calcium diets and minimal sun exposure.
Osteoporosis results from the loss of calcium from the bones and can lead to fractures.(6)
Vitamin D Toxicity
Health Canada recommends that individuals should not exceed 2000 IU of vitamin D per day (including diet and supplements); unless advised by your healthcare provider.(7) Getting vitamin D toxicity is rare; as long as you make healthy lifestyle choices and follow the advice of your healthcare provider.
Things to Keep in Mind
-Vitamin D3 increases calcium absorption as much as 30-80 percent.
-Based on geographical location, it may be difficult to obtain vitamin D from sunlight year round. -Look for foods that have vitamin D added to them to help you meet your daily needs.
Created by Mia Kubrak for The Women’s Midlife Health Program
Nursing Education Program of Saskatchewan
January 2010 updated August 2010
Reference:
1 Health Canada (2007). Vitamin D for people over 50: Background Retrieved January 7, 2010 from www.hc-sc.gc.ca/fn-an/food-guide- aliment/context/evid-fond/vita_d-eng.php
2 Osteoporosis Canada (2010). Vitamin D: A key factor in good calcium absorption. Retrieved July 15, 2010 from http://www.osteoporosis.ca/index.php/ci_id/5536/la_id/1.htm
3 Hegsted, D.M. (2001). Fractures, calcium, and the modern diet. American Journal of Clinical Nutrition, 74(5), p. 571-573.
4 Feskanich, D., Willett, W.C., Colditz, G.A. (2003). Calcium, vitamin d, milk consumption, and hip fractures: A prospective study among postmenopausal women. American Journal of Clinical Nutrition, 77 (2), p. 504-511.
5 Pfeifer, M., Begerow, B., Minne, H.W., Suppan, K., Fahrleitner-Pammer, A., Dobnig, H.(2009). Effects of a long-term vitamin d and cal- cium supplementation on falls and parameters of muscle function in community-dwelling older individuals. Osteoporosis International, 20(2), p.315-322.
6 Whitney E., Rolfes S.R. (2005). Understanding Nutrition (10th ed.). Wadsworth, Thomson.
7 Eating Well with Canada’s Food Guide, 2011 from http://www.hc-sc.gc.ca/fn-an/food-guide-aliment/index-eng.php
8 National Osteoporosis Foundation (2008).Vitamin D Recommendations. Retrieved January 6, 2010 from http://www.nof.org/preven- tion/vitaminD.htm
9 Calcium and Vitamin D: Important at Every Age. Retrieved January 8, 2010 from www.niams.nih.gov/Health_Info/Bone/Bone_ Health/Nutrition/default.asp
10 Pfeifer, M., Begerow, B., Minne, H.W., Suppan, K., Fahrleitner-Pammer, A., Dobnig, H.(2009). Effects of a long-term vitamin d and cal- cium supplementation on falls and parameters of muscle function in community-dwelling older individuals. Osteoporosis International, 20(2), p.315-322.
11 Health Canada (2007). Vitamin D for people over 50: Background Retrieved January 7, 2010 from www.hc-sc.gc.ca/fn-an/food-guide- aliment/context/evid-fond/vita_d-eng.php
12 National Osteoporosis Foundation (2008). Calcium Recommendation. Retrieved January 6, 2010 from http://www.nof.org/preven- tion/calcium2.htm
1 Health Canada (2007). Vitamin D for people over 50: Background Retrieved January 7, 2010 from www.hc-sc.gc.ca/fn-an/food-guide- aliment/context/evid-fond/vita_d-eng.php
2 Osteoporosis Canada (2010). Vitamin D: A key factor in good calcium absorption. Retrieved July 15, 2010 from http://www.osteoporosis.ca/index.php/ci_id/5536/la_id/1.htm
3 Hegsted, D.M. (2001). Fractures, calcium, and the modern diet. American Journal of Clinical Nutrition, 74(5), p. 571-573.
4 Feskanich, D., Willett, W.C., Colditz, G.A. (2003). Calcium, vitamin d, milk consumption, and hip fractures: A prospective study among postmenopausal women. American Journal of Clinical Nutrition, 77 (2), p. 504-511.
5 Pfeifer, M., Begerow, B., Minne, H.W., Suppan, K., Fahrleitner-Pammer, A., Dobnig, H.(2009). Effects of a long-term vitamin d and cal- cium supplementation on falls and parameters of muscle function in community-dwelling older individuals. Osteoporosis International, 20(2), p.315-322.
6 Whitney E., Rolfes S.R. (2005). Understanding Nutrition (10th ed.). Wadsworth, Thomson.
7 Eating Well with Canada’s Food Guide, 2011 from http://www.hc-sc.gc.ca/fn-an/food-guide-aliment/index-eng.php
8 National Osteoporosis Foundation (2008).Vitamin D Recommendations. Retrieved January 6, 2010 from http://www.nof.org/preven- tion/vitaminD.htm
9 Calcium and Vitamin D: Important at Every Age. Retrieved January 8, 2010 from www.niams.nih.gov/Health_Info/Bone/Bone_ Health/Nutrition/default.asp
10 Pfeifer, M., Begerow, B., Minne, H.W., Suppan, K., Fahrleitner-Pammer, A., Dobnig, H.(2009). Effects of a long-term vitamin d and cal- cium supplementation on falls and parameters of muscle function in community-dwelling older individuals. Osteoporosis International, 20(2), p.315-322.
11 Health Canada (2007). Vitamin D for people over 50: Background Retrieved January 7, 2010 from www.hc-sc.gc.ca/fn-an/food-guide- aliment/context/evid-fond/vita_d-eng.php
12 National Osteoporosis Foundation (2008). Calcium Recommendation. Retrieved January 6, 2010 from http://www.nof.org/preven- tion/calcium2.htm
Improving Women's Lives Through Better Health in Mid-Life and Beyond
