Your body makes Vitamin D when you’re in the sun. But sunscreen, dark winters, and days spent indoors mean you may need more for healthy bones.
Vitamin D has been in the news a lot lately for its role in our health. Here are some answers to help you understand what you and your family should do.
WHY DO I NEED VITAMIN D?
Vitamin D helps your body use calcium and phosphorous to build and maintain strong bones. If you have too little in your blood, your bones will not get the calcium they need. This can lead to rickets in children, which causes skeletal deformities. In adults, a lack of Vitamin D can lead to osteomalacia, which results in weak muscles and bones. Together with calcium, Vitamin D helps protect older adults from osteoporosis, too. You may not know you are deficient until you break a bone.
Recent research also suggests that Vitamin D might help protect against high blood pressure, cancer, and several autoimmune diseases, as well as boosting immunity, although Health Canada says the evidence does not show a cause-and-effect relationship.
HOW MUCH DO I NEED?
Health Canada increased its recommended daily intake of Vitamin D in 2010 (see table), but cautioned against exceeding upper tolerance levels. Too much Vitamin D can cause too much calcium to be deposited in the body, leading to calcification of the kidneys, and other tissues, including the heart, lungs, and blood vessels.
|AGE GROUP||RECOMMENDED DIETARY ALLOWANCE (RDA) PER DAY||TOLERABLE UPPER INTAKE LEVEL (UL) PER DAY|
|Infants 0-6 months||400 IU (10 mcg) *||1000 IU (25 mcg)|
|Infants 7-12 months||400 IU (10 mcg) *||1500 IU (38 mcg)|
|Children 1-3 years||600 IU (15 mcg)||2500 IU (63 mcg)|
|Children 4-8 years||600 IU (15 mcg)||3000 IU (75 mcg)|
|Children and Adults 9-70 years||600 IU (15 mcg)||4000 IU (100 mcg)|
|Adults > 70 years||800 IU (20 mcg)||4000 IU (100 mcg)|
|Pregnancy & Lactation||600 IU (15 mcg)||4000 IU (100 mcg)|
*Adequate Intake rather than Recommended Dietary Allowance.
Source: Health Canada
WHO IS AT RISK?
People most at risk for Vitamin D deficiency:
- those with low sun exposure
- obese people
- dark-skinned people
- infants who are exclusively breastfed
HOW CAN I GET VITAMIN D?
You can get Vitamin D from some dietary sources including fatty fish, and fortified milk. One cup of fortified milk has about 110 IU of Vitamin D. That means an adult would have to drink nearly six glasses a day! A 75-gram serving of salmon contains 400 to 700 IU depending on the type. Bluefin tuna is a very good source, similar to salmon, but white, canned tuna is not. Cod liver oil is also an excellent source. Some prepared breakfast cereals and juices are also fortified with Vitamin D. Check the label.
Your body also makes Vitamin D when the sun’s rays strike your skin. Canadians should be able to get enough sun exposure in our sunniest months to produce the Vitamin D we need. Because we need to protect our skin from harmful rays, however, and because many Canadians spend most time indoors, we may not always get enough from the sun. Also, people with dark skin will not synthesize as much. Especially in late fall, winter, and early spring, it is difficult for Canadians to produce enough Vitamin D from sun exposure.
For these reasons, some Canadians will want to consider Vitamin D supplements. Health Canada recommends that, in addition to following Canada’s Food Guide, everyone over the age of 50 should take a daily Vitamin D supplement of 400 IU. Breastfeeding mothers should also talk to their doctors about Vitamin D supplements for babies.
© McNeil Consumer Healthcare, division of Johnson & Johnson Inc. 2012