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Learning About Vitamin D

Why is it important to get enough vitamin D?

Your body needs vitamin D to absorb calcium. Calcium keeps your bones and muscles, including your heart, healthy and strong. If your muscles don't get enough calcium, they can cramp, hurt, or feel weak. You may have long-term (chronic) muscle aches and pains.

If you don't get enough vitamin D throughout life, you have an increased chance of having thin and brittle bones (osteoporosis) in your later years. Children who don't get enough vitamin D may not grow as much as others their age. They also have a chance of getting a rare disease called rickets. It causes weak bones.

Vitamin D and calcium are added to many foods. And your body uses sunshine to make its own vitamin D.

How much vitamin D do you need?

The recommended dietary allowance (RDA) for vitamin D ranges from 400 IU to 600 IU (international units) every day for people ages 1 through 70. The RDA for adults 71 and older is 800 IU every day.

Most Canadians do not get enough vitamin D from food or sun and need supplements.
Alberta Health Services recommends:

  • Albertans from birth to age 50 take a vitamin D supplement of 400 IU each day.
  • Adults over age 50 take a vitamin D supplement of 1,000 IU each day.

Do not take more than 4,000 IU of vitamin D a day as a supplement without talking to your healthcare provider first.

Osteoporosis Canada says Canadians can't get enough vitamin D through diet alone and recommends routine vitamin D supplements for all adults.

How can you get more vitamin D?

Foods that contain vitamin D include:

  • Salmon, tuna, and mackerel. These are some of the best foods to eat when you need to get more vitamin D.
  • Cheese, egg yolks, and beef liver. These foods have vitamin D in small amounts.
  • Milk, plant-based beverages, orange juice, yogurt, and margarine, which have vitamin D added to them.

Some people don't make vitamin D as well as others. They may have to take extra care in getting enough vitamin D.

Things that reduce how much vitamin D your body has include:

  • Having dark skin.
  • Age, especially if you are older than 65.
  • Digestive problems, such as Crohn's or celiac disease.
  • Liver and kidney disease.
  • Using sunscreen or clothing to cover your skin.
  • It can be difficult to get enough vitamin D from food alone. Adults over age 50 should take a 1000 IU vitamin D supplement daily year-round.

Osteoporosis Canada says Canadians can't get enough vitamin D through diet alone and recommends routine vitamin D supplements for all adults.

Are there any risks from taking vitamin D?

  • Too much vitamin D:
    • Can damage your kidneys.
    • Can cause nausea and vomiting, constipation, and weakness.
    • Raises the amount of calcium in your blood. If this happens, you can get confused or have an irregular heart rhythm.
  • Health Canada recommends adults not go over 4000 IU of vitamin D daily. There are no additional benefits of vitamin D over this limit.
  • Vitamin D may interact with medicines. Tell your doctor about all of the medicines you take, including prescription, non-prescription, and natural health products. Tell your doctor about all of your current medical problems.

Where can you learn more?

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