This complementary and alternative medicine (CAM) information summary provides an overview of the use of Essiac and Flor•Essence, which are proprietary herbal tea mixtures, as treatments for patients with cancer. The summary includes a brief history of the development of Essiac and Flor•Essence; a review of laboratory, animal, and human studies; and possible side effects associated with Essiac and Flor•Essence use.

This summary contains the following key information:

• Essiac and Flor•Essence are herbal tea mixtures originally developed in Canada. There may be differences between Essiac and Flor•Essence in their mixture content and effects.
• These products are marketed worldwide as dietary supplements.
• Proponents have claimed that Essiac and Flor•Essence can help detoxify the body, strengthen the immune system, and fight cancer.
• Proponents of Essiac have claimed further that it can help relieve pain, improve quality of life, and reduce tumor size.
• Molecules with antioxidant, anti-inflammatory, anticancer, or immunostimulatory activity have been identified in the individual herbs in the Essiac and Flor•Essence formulas.
• No controlled data are available from human studies to suggest that Essiac or Flor•Essence can be effective in the treatment of patients with cancer.
• Some evidence suggests that Flor•Essence may increase tumor formation in an animal model of breast cancer.

Many of the medical and scientific terms used in the summary are hypertext linked (at first use in each section) to the NCI Dictionary ¹, which is oriented toward nonexperts. When a linked term is clicked, a definition will appear in a separate window. All linked terms and their corresponding definitions will appear in a glossary in the printable version of the summary.

Reference citations in some PDQ CAM information summaries may include links to external Web sites that are operated by individuals or organizations for the purpose of marketing or advocating the use of specific treatments or products. These reference citations are included for informational purposes only. Their inclusion should not be viewed as an endorsement of the content of the Web sites, or of any treatment or product, by the PDQ Cancer CAM Editorial Board or the National Cancer Institute (NCI).

Glossary Terms

Having to do with reducing inflammation.

A substance that protects cells from the damage caused by free radicals (unstable molecules made by the process of oxidation during normal metabolism). Free radicals may play a part in cancer, heart disease, stroke, and other diseases of aging. Antioxidants include beta-carotene, lycopene, vitamins A, C, and E, and other natural and manufactured substances.

A term for diseases in which abnormal cells divide without control. Cancer cells can invade nearby tissues and can spread to other parts of the body through the blood and lymph systems. There are several main types of cancer. Carcinoma is cancer that begins in the skin or in tissues that line or cover internal organs. Sarcoma is cancer that begins in bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue. Leukemia is cancer that starts in blood-forming tissue such as the bone marrow, and causes large numbers of abnormal blood cells to be produced and enter the blood. Lymphoma and multiple myeloma are cancers that begin in the cells of the immune system. Central nervous system cancers are cancers that begin in the tissues of the brain and spinal cord.

A type of research study that tests how well new medical approaches work in people. These studies test new methods of screening, prevention, diagnosis, or treatment of a disease. Also called a clinical trial.

CAM. Forms of treatment that are used in addition to (complementary) or instead of (alternative) standard treatments. These practices generally are not considered standard medical approaches. Standard treatments go through a long and careful research process to prove they are safe and effective, but less is known about most types of CAM. CAM may include dietary supplements, megadose vitamins, herbal preparations, special teas, acupuncture, massage therapy, magnet therapy, spiritual healing, and meditation. Also called CAM.

To make something less poisonous or harmful. It may refer to the process of removing toxins, poisons, or other harmful substances from the body.

A product that is added to the diet. A dietary supplement is taken by mouth, and usually contains one or more dietary ingredient (such as vitamin, mineral, herb, amino acid, and enzyme). Also called nutritional supplement.

An herbal tea mixture that contains burdock root, Indian rhubarb root, sheep sorrel, and slippery elm bark. It has been claimed to remove toxins from the body, make the immune system stronger, relieve pain, control diabetes, treat AIDS, reduce tumor size, increase cancer survival, and improve quality of life. No clinical trial using Essiac in humans has been reported in a peer-reviewed, scientific journal, and the FDA has not approved the use of Essiac for the treatment of any medical conditions.

Having to do with plants.

The complex group of organs and cells that defends the body against infections and other diseases.

A substance that increases the ability of the immune system to fight infection and disease.

Research done in a laboratory. These studies may use test tubes or animals to find out if a drug, procedure, or treatment is likely to be useful. Laboratory studies take place before any testing is done in humans.

The smallest particle of a substance that has all of the physical and chemical properties of that substance. Molecules are made up of one or more atoms. If they contain more than one atom, the atoms can be the same (an oxygen molecule has two oxygen atoms) or different (a water molecule has two hydrogen atoms and one oxygen atom). Biological molecules, such as proteins and DNA, can be made up of many thousands of atoms.

Research using animals to find out if a drug, procedure, or treatment is likely to be useful. Preclinical studies take place before any testing in humans is done.

The overall enjoyment of life. Many clinical trials assess the effects of cancer and its treatment on the quality of life. These studies measure aspects of an individual’s sense of well-being and ability to carry out various activities.

A problem that occurs when treatment affects healthy tissues or organs. Some common side effects of cancer treatment are fatigue, pain, nausea, vomiting, decreased blood cell counts, hair loss, and mouth sores.