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Dietary and Herbal Supplements

What is a dietary supplement?

A diet is a plan or strategy for eating with certain foods included and eliminated. Adding anything to your regular diet to improve your health or healing is considered a dietary supplement. It is considered alternative therapy when it is offered outside the medical care setting and the proponents make claims that it will produce a medical benefit. Most of your nutritional needs should be met by eating a balanced diet.

Can dietary supplements help people with cancer?

While there is no scientific evidence that an individual’s diet promotes curing cancer, medical nutrition therapy provided by a registered dietitian may be a component of your regular medical care. You should be aware that some supplements that are potentially helpful in decreasing the risk of developing cancer have been shown to reduce the effectiveness of chemotherapy and radiation therapy during cancer treatment. There are also many possible side effects from certain diets, such as weakness, diarrhea, or kidney problems, and many claims made by manufacturers of such supplements are not scientifically proven. Following diets that are not approved by your physician or registered dietitian can be dangerous at any time, especially during cancer treatment. Consult your physician or registered dietitian before making any changes to your regular diet.

What are the different dietary supplements' intended function?

The following are examples of possible dietary supplements and their intended function. Always consult your physician before taking any dietary supplements.

Dietary supplements can be purchased at grocery stores, health food stores, and drug stores. Dietary supplements come in many forms, including:

Are there any possible problems or complications?

Not all medications and dietary supplements available over the counter are proven to be safe. The US Food and Drug Administration (FDA) does not require manufacturers of these products to print potential side effects on their labels. And if they do receive complaints, the FDA cannot take a dietary supplement or herbal product off the market unless scientists can prove that the product is unsafe.

Each dietary supplement is different. Because most are scientifically untested, the side effects are unknown. Many cancer experts caution against self-prescribing vitamins or other dietary supplements. If you are being treated for cancer and you were already taking dietary supplements before the cancer was diagnosed, you should immediately discuss with your physician what supplements you are taking, as many supplements could interfere with your treatment.

What is an herbal supplement?

Herbal supplements are products made from plants for use in the treatment and management of certain diseases and medical conditions. Many prescription drugs and over-the-counter medications are also made from plant derivatives. These products contain only purified ingredients and are regulated by the FDA. Herbal supplements may contain entire plants or plant parts.

Herbal supplements come in all forms: dried, chopped, powdered, capsule, or liquid, and can be used in various ways, including:

Can herbal supplements help people with cancer?

The practice of using herbal supplements dates back thousands of years. Today, there is resurgence in the use of herbal supplements among American consumers. However, herbal supplements are not for everyone. In fact, some herbal products can cause problems for persons undergoing cancer therapies, such as chemotherapy or radiation therapy. Because they are not subject to close scrutiny by the FDA or other governing agencies, the use of herbal supplements is controversial. Do not take any herbal supplements without first consulting your physician.

The FDA and herbal supplements:

Herbal supplements are considered by the FDA to be foods, not drugs, and therefore are not subject to the same testing, manufacturing, and labeling standards and regulations as drugs.

Until 1994, the FDA had disallowed health claims of any kind on herbal supplements. The passage of the federal Dietary Supplement and Health Education Act (DSHEA) in 1994 started to reverse this trend. As recently as 2000, the FDA updated the laws governing the labeling of herbal supplements. Consumers now can see labels that explain how herbs can influence different actions in the body. However, herbal supplement labels still cannot state anything about treating specific medical conditions, because herbal supplements are not subject to clinical trials or to the same manufacturing standards as prescription or traditional over-the-counter drugs. Do not self-diagnose. Consult your physician before taking herbal supplements.

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