Dietary and herbal supplements
What is a dietary supplement?
Can dietary supplements help people with cancer?
What are the different dietary supplements’ intended function?
Are there any possible problems or complications?
What is an herbal supplement?
Can herbal supplements help people with cancer?
The FDA and herbal supplements
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.
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 also are 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.
The following are examples of possible dietary supplements and their intended function. Always consult your physician before taking any dietary supplements.
Vitamins are key nutrients that are essential in small quantities for the body to grow and stay strong. Your body needs vitamins either from your diet or from supplements. Examples of vitamins include vitamin A, vitamin D and vitamin E.
Minerals are nutrients that are required to maintain health. Your body needs minerals either from your diet or from supplements. Examples of mineral include calcium, magnesium and zinc.
Antioxidants protect the body’s cells from damage caused by free radicals (by-products of the body’s normal chemical processes) and can also protect against some side effects of cancer treatment such as organ damage, low blood counts and diarrhea.
Enzymes are proteins that are produced by the body to start and accelerate chemical processes such as digestion. Some enzymes can be taken as supplements.
- Amino acids
Amino acids are the building blocks of the body’s proteins. Proteins are necessary for growth and development. Some amino acids are produced by the body and some (essential amino acids) come from your diet.
- Plant extracts
Plant extracts are sometimes used by practitioners of Chinese medicine to help nourish the body. Traditional Chinese medicine works to restore a balance of energy, body and spirit for good health. When cancer causes imbalances, practitioners may attempt treatment with combinations of herbs, minerals and plant extracts.
Hormones are chemicals produced in glands in the body that affect the functions of organs and tissues.
Herbs are plants that are used in food preparation or for medicinal purposes.
- Homeopathic products
Traditionally, homeopathic products are small doses of natural substances, usually medicinal substances and/or herbs, diluted with water or alcohol. Homeopathic medicine is based on the belief that what causes symptoms in a healthy person can cure the same symptoms in someone who is not healthy. Homeopathic products are intended to initiate healing, not eliminate the symptoms.
- Other products
Bioengineered foods are considered dietary supplements, but are not drugs.
Dietary supplements can be purchased at grocery stores, health food stores and drug stores. Dietary supplements come in many forms, including:
- Power bars
Not all medications and dietary supplements available over the counter are proven to be safe. The U.S. Food and Drug Administration 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.
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:
- Swallowed as pills.
- Brewed as tea.
- Applied to the skin as gels.
- Added to bath water.
The practice of using herbal supplements dates back thousands of years. Today, there is a 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.
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 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.