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Cancer prevention and dietary supplements



You may be wondering if taking dietary supplements can help lower your risk of cancer. Read on to learn whether taking vitamin, mineral or other supplements is right for you.

What are dietary supplements?

Dietary supplements may include things like vitamins, minerals and natural health products.

Are dietary supplements recommended to protect against cancer? 

No. There is no sure evidence that dietary supplements protect against cancer.  In some cases, dietary supplements may be harmful.

What is the best way to protect against cancer? 

Eating a balanced diet with a variety of plant foods is one of the best ways to lower your risk of cancer.  Plant foods include vegetables, fruit, whole grains, nuts, seeds and legumes (beans, peas and lentils). Plant foods protect your health when they are eaten as whole foods, not in supplement form. Plant foods also have many nutrients, which is more beneficial than taking one nutrient, like Vitamin C, as a dietary supplement. Read Lowering your Risk of Cancer for more way to lower your cancer risk.

Who should be taking dietary supplements?

Certain people need dietary supplements for different reasons.

  • Adults over the age of 50 need additional vitamin D and may need additional vitamin B12.
  • Women who may become or are pregnant need a folic acid supplement.
  • People who follow a vegan diet or who do not eat foods from all four food groups may need specific vitamin or mineral supplements.
  • People with food allergies, osteoporosis or other medical conditions may need specific dietary supplements to fill a nutrient gap or give extra nutrients.

If I choose to take a dietary supplement, what should I look out for? 

Take dietary supplements when your doctor or health care provider recommends them. Avoid taking individual vitamins and minerals, as there may be a risk of taking too much this way. Even “natural” dietary supplements can be harmful. These may contain vitamins, minerals and other substances in amounts that may have unwanted effects. When you buy a dietary supplement, always look for a Drug Identification Number (DIN) or Natural Product Number (NPN).  These numbers tell you that the supplement meets Health Canada’s standards.

Bottom line 

Dietary supplements do not provide the same cancer protection benefits as whole foods and may be potentially harmful.  Discuss dietary supplements with your doctor or health care provider to find out if taking dietary supplements is right for you.

You might be interested in 

Lowering your risk of cancer Lowering your risk of cancer: You and your environment Lowering your risk of cancer: What about specific foods?

Last Update – July 11, 2016

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