Dietary and Herbal Supplements for Cancer

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 clear-cut 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. Some supplements may potentially be helpful in decreasing the risk of developing cancer although the evidence for this is not clear, and many claims made by manufacturers of such supplements are not scientifically proven. On the other hand, concerns have been raised that some supplements might interfere with the safety or effectiveness of some cancer treatments. Be sure to let your doctor know about all of the supplements you are taking (including multivitamins) before starting treatment.

There are also many possible side effects from certain diets, such as weakness, diarrhea, or kidney problems. Following diets that are not approved by your doctor or registered dietitian can be dangerous at any time, especially during cancer treatment. Consult your doctor or registered dietitian before making any changes to your regular diet.

What are the different dietary supplements' intended functions?

The following are examples of possible dietary supplements and their intended functions. Always consult your doctor before taking any dietary supplements:

  • Vitamins. 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, vitamin C, and vitamin E.

  • Minerals. Minerals are elemental nutrients that are required to maintain health. Your body needs minerals either from your diet or from supplements. Examples of minerals include calcium, magnesium, and zinc.

  • Antioxidants. Antioxidants protect the body’s cells from damage caused by free radicals (by-products of the body’s normal chemical processes).

  • Enzymes. 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 (called 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. Hormones are chemicals produced in glands in the body that affect the functions of organs and tissues.

  • Herbs. Herbs are plants that are used in food preparation or for medicinal purposes.

  • Homeopathic products. Traditionally, homeopathic products are very 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.

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

  • Pills

  • Capsules

  • Liquids

  • Power bars

  • Cookies

  • Powders

  • Elixirs

Are there any possible problems or complications?

Not all medications and dietary supplements available over the counter are proven to be safe.

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 doctor what supplements you are taking, as some supplements may 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  unlike herbal supplements, are closely 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

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 may cause problems for people undergoing cancer treatment. 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 doctor.

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.

Do not self-diagnose. Consult your doctor before taking herbal supplements.


Bayhealth is Southern Delaware’s healthcare leader with hospitals in Dover and in Milford. Bayhealth provides a wide range of medical services, including cardiovascular, cancer, orthopaedics and rehabilitation, pediatrics, respiratory care, sleep care, surgical weight loss, women’s services and walk-in medical care. Search for nursing jobs, and health classes and events. Find doctors affiliated with Bayhealth Medical Center or a Delaware hospital near you.