Chlorella
OTHER NAME(S): chlorella
Overview
Chlorella is a type of green algae that contains large amounts of fiber, healthy fats, vitamins, and minerals. Some chlorella products are put in foods or drinks for added nutrition. Chlorella dietary supplements are taken for many reasons, but their benefits are not well defined. Although chlorella appears to be well tolerated, there is not enough research to know what side effects it may cause. Before taking chlorella, make sure to tell your health care provider about all of your health conditions and any medicines or supplements you may be using.
Uses
What is chlorella used for?
Chlorella is used as a source of added nutrition. It is also used for other reasons, although its benefits are not well defined. Some common reasons for using chlorella include the following.
- Diabetes
- High blood pressure (hypertension)
- High cholesterol
- Liver problems
- To improve physical performance
Note: The FDA has not reviewed chlorella for safety and effectiveness. Learn more about dietary supplements here.
How does chlorella work (mechanism of action)?
Chlorella refers to a genus of green algae. These algae contain proteins and omega-3 fatty acids, as well as large amounts of iron, vitamin D, vitamin B12 (cyanocobalamin), and vitamin B9 (folic acid). Chlorella powders and tablets are often put in shakes and other foods as a source of added nutrition. Most products that contain chlorella are made from Chlorella vulgaris, although other chlorella species may also be used.
Supplements that contain chlorella are marketed for many uses. Some of the chemicals in chlorella may work as antioxidants and help reduce swelling (inflammation). But most research shows that these supplements do not lower blood pressure or cholesterol levels by a meaningful amount. Also, research on using chlorella for liver health or to improve physical performance is limited and unclear. Overall, the benefits of taking chlorella for reasons other than nutrition are not well defined.
Herbal products, such as chlorella, naturally contain many different chemicals. The amounts of each chemical in a specific chlorella product may vary. Some, none, or all of these chemicals may have effects on the body. These effects may change depending on how much of each chemical is found in the product you are using.
How should I store chlorella?
You should store chlorella according to the product label. Most dietary supplements should be kept in a cool, dry location that is out of the reach of children and pets and not in direct sunlight.
Side Effects
What are the most common side effects of chlorella?
Chlorella seems to be well tolerated. But there is not enough research to know what the common side effects may be. Tell your health care provider if you have any side effects that bother you.
There may be other side effects of chlorella that are not listed here. Contact your health care provider if you think you are having a side effect of a supplement. In the U.S., you can report side effects to the FDA at www.safetyreporting.hhs.gov or by calling 888-SAFEFOOD (888-723-3366). In Canada, you can report side effects to Health Canada at www.health.gc.ca/medeffect or by calling 866-234-2345.
What are the serious side effects of chlorella?
While less common, the most serious side effects of chlorella are described below, along with what to do if they happen.
Severe Allergic Reactions. Chlorella may cause allergic reactions, which can be serious. Stop taking chlorella and get help right away if you have any of the following symptoms of a serious allergic reaction.
- Breathing problems or wheezing
- Racing heart
- Fever or general ill feeling
- Swollen lymph nodes
- Swelling of the face, lips, mouth, tongue, or throat
- Trouble swallowing or throat tightness
- Itching or skin rash
- Bumps on the skin called hives that can be red, pink, white, or brown depending on your skin tone
- Nausea or vomiting
- Dizziness, feeling lightheaded, or fainting
- Stomach cramps
- Joint pain
Precautions
Who should not use chlorella?
Allergies to Ingredients. People who are allergic to any of the following should not take chlorella.
- Chlorella
- Any of the ingredients in the specific product
Your pharmacist can tell you all of the ingredients in the specific chlorella products they stock.
What should I know about chlorella before using it?
Chlorella is a dietary supplement. It cannot be marketed to treat or cure a disease.
Read and follow the directions on the specific product you are taking, or take it as recommended by your health care provider.
Keep chlorella out of the reach of children.
Natural products, such as chlorella, contain many different chemicals. The amount of each chemical in a specific chlorella product can change for many reasons, including the area where the algae grew, the weather during growth, the time of year when it was harvested, and the way that it was processed after harvest. If you switch to a new bottle or a different brand, you may not have the same effects or side effects because of this variability. Talk to your health care provider if you have questions or concerns.
Chlorella is available in many forms, including a dried and ground powder, capsule, and tablet. Some of these products are meant to be mixed with foods or drinks. Each of these forms may contain different amounts of the chemicals that are naturally found in this algae.
If you are taking chlorella powder, use an appropriate measuring device to measure the powder, such as the device included with the product. Read the label carefully, measure the amount stated on the label, and mix the powder with fluid as directed.
The FDA has not tested chlorella products to confirm that they contain the ingredients stated on their labels. Some dietary supplements have been tested by third-party organizations to confirm that they contain the ingredients listed on their labels and do not contain any harmful chemicals. Learn more about how to choose a safe dietary supplement product here.
What should I tell my health care provider before using chlorella?
Tell your health care provider about all of your health conditions and any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. This will help them know if chlorella is right for you.
In particular, make sure that you discuss any of the following.
Pregnancy. It is not known if or how chlorella could affect pregnancy or harm a fetus. Tell your health care provider if you are pregnant or plan to become pregnant.
Breastfeeding. Some of the nutrients in chlorella pass into breast milk. Tell your health care provider if you are breastfeeding or plan to breastfeed.
Interactions
Does chlorella interact with foods or drinks?
There are no known interactions between chlorella and foods or drinks.
It is unknown if drinking alcohol will affect chlorella.
Does chlorella interact with medicines (drug interactions)?
There are no known interactions between chlorella and medicines. Always tell your health care provider about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using.
The interactions between chlorella and medicines are not fully understood. As with most dietary supplements, the research on drug interactions with chlorella is incomplete. Always check with your health care provider before taking chlorella with any medicines.
Dosing
What should I do if I accidentally use too much chlorella?
If you or someone else has used too much chlorella, get medical help right away, call 911, or contact a Poison Control center at 800-222-1222.
Chlorella is available in a wide range of doses and forms. Read the product label closely, and speak with a health care provider about how to take chlorella safely. Do not take double or extra doses, even if you miss a dose.
References
- Clinical Nutrition Research: “Effect of Chlorella vulgaris on liver function biomarkers: a systematic review and meta-analysis.”
- Complementary Therapies in Medicine: “Effect of supplementation with Chlorella vulgaris on lipid profile in adults: a systematic review and dose-response meta-analysis of randomized controlled trials.”
- Frontiers in Nutrition: “The nutritional efficacy of chlorella supplementation depends on the individual gut environment: a randomised control study.”
- Journal of Complementary and Integrative Medicine: “The effect of Chlorella vulgaris on obesity related metabolic disorders: a systematic review of randomized controlled trials.”
- Nutrients: “Bioactivity of macronutrients from chlorella in physical exercise,” “Potential of chlorella as a dietary supplement to promote human health,” “The role of Chlorella and Spirulina as adjuvants of cardiovascular risk factor control: a systematic review and meta-analysis of randomised controlled trials.”