Chlorella

Last Editorial Review: 6/11/2021
Other Name(s):

Algue Verte d'Eau Douce, Bulgarian Chlorella, Bulgarian Green Algae, Chinese Chlorella, Chlorella Algae, Chlorella pyrenoidosa, Chlorella vulgaris, Chlorelle, Clorela, Freshwater Green Algae, Freshwater Seaweed, Green Alga, Green Algae, Japanese Chlorella, Seaweed, Yaeyama Chlorella.

Overview

Chlorella is a type of algae that grows in fresh water. The whole plant is used to make nutritional supplements and medicine.

Most of the chlorella that is available in the U.S. is grown in Japan or Taiwan. It is processed and made into tablets and liquid extracts. These extracts contain "chlorella growth factor," which is described as a water-soluble extract of chlorella containing chemicals including amino acids, peptides, proteins, vitamins, sugars, and nucleic acids.

Be aware that chlorella products can vary significantly depending on the way “the crop” used to make them was cultivated, harvested, and processed. Investigators have found that dried preparation of chlorella can contain from 7% to 88% protein, 6% to 38% carbohydrate, and 7% to 75% fat.

As a medicine, chlorella is used for preventing cancer, reducing radiation treatment side effects, stimulating the immune system, improving response to flu vaccine, increasing white blood cell counts (especially in people with HIV infection or cancer), preventing colds, protecting the body against toxic metals such as lead and mercury, and slowing the aging process.

Chlorella is also used to increase “good” bacteria in the intestine in order to improve digestion; and to help treat ulcers, colitis, Crohn's disease, and diverticulosis.

Some people also use chlorella for the prevention of stress-related ulcers; treatment of constipation, bad breath, and hypertension; as an antioxidant; to reduce cholesterol; to increase energy; to detoxify the body; and as a source of magnesium to promote mental health, relieve premenstrual syndrome (PMS), and reduce asthma attacks. It is also used for fibromyalgia.

Chlorella is applied to the skin for treating skin ulcers, rashes caused by radiation treatment, and a sexually transmitted disease called trichomoniasis.

How does it work?

Chlorella is a good source of protein, fats, carbohydrates, fiber, chlorophyll, vitamins, and minerals. The cell wall of chlorella must be broken down before people can digest it.

QUESTION

Next to red peppers, you can get the most vitamin C from ________________. See Answer

Uses & Effectiveness

Insufficient Evidence to Rate Effectiveness for...

More evidence is needed to rate the effectiveness of chlorella for these uses.

Natural Medicines Comprehensive Database rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, and Insufficient Evidence to Rate (detailed description of each of the ratings).

Side Effects

Chlorella is POSSIBLY SAFE when taken by mouth, short-term (up to 2 months). The most common side effects include diarrhea, nausea, gas (flatulence), green discoloration of the stools, and stomach cramping, especially in the first week of use.

Chlorella has caused serious allergic reactions, including asthma and other dangerous breathing problems.

Chlorella can cause skin to become extra sensitive to the sun. Wear sunblock outside, especially if you are light-skinned.

SLIDESHOW

Vitamin D Deficiency: How Much Vitamin D Is Enough? See Slideshow

Special Precautions & Warnings

Pregnancy and breast-feeding: There is not enough reliable information about the safety of taking chlorella if you are pregnant or breast feeding. Stay on the safe side and avoid use.

Iodine sensitivity: Chlorella can contain iodine. Therefore, chlorella might cause an allergic reaction in people sensitive to iodine.

Allergy to molds: Chlorella might cause an allergic reaction in people who are also allergic to molds.

Weak immune system (immunodeficiency): There is a concern that chlorella might cause “bad” bacteria to take over in the intestine of people who have a weak immune system. Be careful with chlorella if you have this problem.

“Autoimmune diseases” such as multiple sclerosis (MS), lupus (systemic lupus erythematosus, SLE), rheumatoid arthritis (RA), or other conditions: Chlorella might cause the immune system to become more active, and this could increase the symptoms of autoimmune diseases. If you have one of these conditions, it's best to avoid using chlorella.

Interactions


Medications that decrease the immune system (Immunosuppressants)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.

Chlorella might make the immune system more active. That could decrease the effectiveness of medications that are used to decrease (suppress) the immune system.

Some medications that suppress the immune system include azathioprine (Imuran), basiliximab (Simulect), cyclosporine (Neoral, Sandimmune), daclizumab (Zenapax), muromonab-CD3 (OKT3, Orthoclone OKT3), mycophenolate (CellCept), tacrolimus (FK506, Prograf), sirolimus (Rapamune), prednisone (Deltasone, Orasone), corticosteroids (glucocorticoids), and others.


Warfarin (Coumadin)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.

Chlorella contains large amounts of vitamin K. Vitamin K is used by the body to help blood clot. Warfarin (Coumadin) is used to slow blood clotting. By helping the blood clot, chlorella might decrease the effectiveness of warfarin (Coumadin). Be sure to have your blood checked regularly. The dose of your warfarin (Coumadin) might need to be changed.

Dosing

The appropriate dose of chlorella depends on several factors such as the user's age, health, and several other conditions. At this time there is not enough scientific information to determine an appropriate range of doses for chlorella. Keep in mind that natural products are not always necessarily safe and dosages can be important. Be sure to follow relevant directions on product labels and consult your pharmacist or physician or other healthcare professional before using.

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