The majority of adults in the world take one or more dietary supplements either every day or occasionally. Today's dietary supplements include vitamins, minerals, herbals and botanicals, amino acids, enzymes, and many other products. Dietary supplements come in a variety of forms: traditional tablets, capsules, and powders, as well as drinks and energy bars. Popular supplements include vitamins D and E minerals like calcium and iron herbs such as Echinacea and garlic and specialty products like glucosamine, probiotics, and fish oils.
All products labelled as a dietary supplement carry a Supplement Facts panel that lists the contents, amount of active ingredients per serving, and other added ingredients (like fillers, binders, and flavourings). The manufacturer suggests the serving size, but you or your doctor might decide that a different amount is more appropriate for you.
How effective are food supplements?
If you don't eat a nutritious variety of foods, some supplements might help you get adequate amounts of essential nutrients. However, supplements can't take the place of the variety of foods that are important to a healthy diet.
Scientific evidence shows that some dietary supplements are beneficial for overall health and for managing some health conditions. For example, calcium and vitamin D are important for keeping bones strong and reducing bone loss folic acid decreases the risk of certain birth defects and omega-3 fatty acids from fish oils might help some people with heart disease. Other supplements need more study to determine their value.
Safety and risk associated with food supplements
Many supplements contain active ingredients that can have strong effects in the body. Always be alert to the possibility of unexpected side effects, especially when taking a new product.
Supplements are most likely to cause side effects or harm when people take them instead of prescribed medicines or when people take many supplements in combination. Some supplements can increase the risk of bleeding or, if a person takes them before or after surgery, they can affect the person's response to anaesthesia. Dietary supplements can also interact with certain prescription drugs in ways that might cause problems.
Keep in mind that some ingredients found in dietary supplements are added to a growing number of foods, including breakfast cereals and beverages. As a result, you may be getting more of these ingredients than you think, and more might not be better. Taking more than you need is always more expensive and can also raise your risk of experiencing side effects. For example, getting too much vitamin A can cause headaches and liver damage, reduce bone strength, and cause birth defects. Excess iron causes nausea and vomiting and may damage the liver and other organs.
Be cautious about taking dietary supplements if you are pregnant or nursing. Also, be careful about giving them (beyond a basic multivitamin/mineral product) to a child. Most dietary supplements have not been well tested for safety in pregnant women, nursing mothers, or children.
Talk with your doctor before going for food supplements
Let your doctor know which dietary supplements you're taking so that you can discuss what's best for your overall health. Your doctor can help you determine which supplements, if any, might be valuable for you.
Keep a record of the supplements you take in one place, just as you should be doing for all of your medicines. Note the specific product name, the dose you take, how often you take it, and the reason why you use each one. You can also bring the products you use with you when you see your doctor.
Things to keep in mind
Don't decide to take dietary supplements to treat a health condition that you have diagnosed yourself, without consulting your doctor:
- Don't take supplements in place of, or in combination with, prescribed medications without your health care provider's approval.
- Check with your doctor about the supplements you take if you are scheduled to have any type of surgical procedure.
- The term "natural" doesn't always mean safe. A supplement's safety depends on many things, such as its chemical makeup, how it works in the body, how it is prepared, and the dose used.