views updated May 29 2018



Chlorella is a type of single-cell green algae. It is a major component of phytoplankton, which are very small free-floating aquatic plants found in plankton. Chlorella is a popular food supplement, especially in Japan, and is sold as a nutritional supplement in the United States and Canada. There are several species of chlorella, but those most commonly found in supplements are Chlorella vulgaris and Chlorella pyrenoidosa.

General use

Chlorella contains high levels of chlorophyll, protein, iron , vitamins C and B12, beta carotene , and 19 amino acids .

Several studies have indicated that chlorella may be effective in treating some types of cancer , high cholesterol, hypertension (high blood pressure), fibromyalgia syndrome, and in boosting the immune system and detoxifying the body. As is often the case with alternative therapies, there are several studies that dispute the effectiveness of chlorella in treating these medical conditions.

Chlorella's ability to fight cancer cells has been shown in several scientific studies, although the exact mechanisms of how it works are not known. Several scientists believe chlorella stimulates the activity of T-cellsimportant for antibody immunityand macrophages, which are large cells that protect against infection by removing waste products, harmful microorganisms, and other toxins from the bloodstream. Increasing the production of T-cells and macrophages increases interferon levels in the body, enhancing the immune system's ability to fight invading substances such as viruses, bacteria, and chemicals. Interferon is an immune related protein produced by the body, which performs antiviral and antitumor activities.

Studies in laboratory animals suggest some substances in chlorella may reduce bone marrow suppression in patients taking the anticancer drug fluorouracil. In doing this, chlorella may increase the white blood cell and platelet counts, which reduces the risk of infection and bleeding, respectively.

Studies have also shown chlorella can significantly reduce cholesterol levels in laboratory animals. Studies are currently underway to see if it has the same effect on human cholesterol levels.

Chlorella may also help reduce blood pressure in some people with hypertension (high blood pressure). A study reported in the March 2003 issue of Original Internist showed that treatment with 10 grams of chlorella daily for three months significantly improved blood pressure in 25% of the patients.

In a 2000 study, patients with fibromyalgia syndrome (a disorder that causes muscle aches, fatigue , and sleep disorders ) were treated with high doses of chlorella. After two months, the study found significant benefits from chlorella treatment.

Clinical studies of laboratory animals have also shown that chlorella can protect against gamma radiation and other toxic drugs and chemicals, including dioxin. In the intestines, it can deactivate heavy metals such as cadmium, lead, and mercury.

The benefits of chlorella have been disputed. According to an equivocal article about chlorella on the American Cancer Society website, there is no scientific evidence showing chlorella's effectiveness against cancer or any other disease. Limited laboratory and animal research suggests that the algae may have some anticancer properties. One investigation concluded that a protein extract from one type of chlorella prevented the spread of cancer cells in mice. Another study of mice suggested that the extract decreased the side effects of chemotherapy treatment without affecting the potency of anticancer medications.


Chlorella is available in various forms, including capsule, tablet, softgel, powder, and liquid. It is found as a supplement alone or in a combination with other green food extracts such as wheat grass, barley grass , and spirulina (a nutritionally rich microorganism). Capsules and tablets are available in doses of 200500 milligrams (mg). There is no standard dosage but some herbalists recommend 3 grams (g) per day. The average cost of a bottle of 100 capsules (containing approximately 125 mg each) ranges from $9 to $15.


Pregnant and breastfeeding women are advised to use caution and follow the advice of their healthcare professional, since the effects of chlorella have not been studied for these two groups. Caution may also be advised for persons known to be sensitive or allergic to iodine .


Fibromyalgia syndrome
Also called fibromyalgia, a disorder that causes muscle aches, fatigue, and sleep disorders.

Side effects

Although chlorella appears to be safe, no research in humans has been done to determine if the supplement causes any negative side effects. Also, no studies have been done regarding the consequences of long-term use. Mild side effects that have been reported include bloating and nausea , which usually disappear after a few days of use. Some people using chlorella have had allergic reactions and adverse reactions to sunlight. Allergic reaction symptoms include difficulty breathing, chest pain, hives , rash, and itchy or swollen skin. If this happens, the person should seek medical care immediately.


Persons taking the blood-thinning drug known as Coumadin (generic warfarin) are advised to completely avoid chlorella, or use caution and follow the advice of their healthcare professional because some chlorella supplements contain high amounts of vitamin K that may affect the inhibition of blood clots .



Bewicke, Dhyana, and Beverly A Potter. Chlorella: The Emerald Food. Berkeley, CA: Ronin Publishing, 1984.

Drucker, Mark. Chlorella: The Key to Health, Vitality, and Longevity. Greenville, SC: Health & Happiness Publishing, Inc., 2002.

Lee, William H., and Michael E. Rosenbaum. Chlorella. New York, NY: McGraw&-Hill, 1998.

Ley, Beth M. Chlorella, the Ultimate Green Food: Nature's Richest Source of Chlorophyll, DNA, and RNA. Aliso Viejo, CA: BL Publications, 2003.

McCauley, Bob. Confessions of a Body Builder, Rejuvenating the Body with Spirulina, Chlorella, Raw Foods, & Ionized Water. Lansing, MI: Spartan Enterprises, Inc., 2000.


Hori, Yasuko, et al. "Insulin Resistance is Associated with Increased Circulating Level of Thrombin-Activated Fibrinolysis in Type 2 Diabetic Patients." The Journal of Clinical Endocrinology & Metabolism (February 2002): 6605.

Merchant, Randall E., and Cynthia A. Andre. "Abstract: A Review of Recent Clinical Trials of Chlorella for the Treatment of Fibromyalgia, Hypertension, and Ulcerative Colitis." Alternative Therapies in Health and Medicine (May-June 2001): 7991.

Merchant, Randall E., and Cynthia A. Andre. "Dietary Chlorella for Hypertension." Original Internist (March 2003): 2940.

Moreno, Bobbi. "Super-Healthy Treasures from the Sea." Better Nutrition (August 1999): 38.

Nick, Gina L. "Addressing Human Exposure to Environmental Toxins with Chlorella Pyrenoidosa. (Medicinal Properties of Whole Foods)." Townsend Letter for Doctors and Patients (April 2003): 2833.


Mercola, Joseph, M.D. "Chlorella: A Natural Wonder Food." Begin Your Journey to Independent Health <>.

Ken R. Wells


views updated May 14 2018

Chlorella (division Chlorophyta) A genus of non-motile, unicellular green algae. Each cell contains a single, usually cup-shaped, chloroplast. Cells divide to form 2, 4, 8, or 16 daughter cells which resemble the parent cell and are initially enclosed within the parent cell wall. Chlorella is very common in a wide range of aquatic and terrestrial habitats, often colouring small bodies of standing water (e.g. drinking troughs) a pea-soup green.


views updated May 11 2018

chlorella See algae.