Chlorella Benefits, Supplements and Potential Side Effects - Dr. Axe

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Chlorella Benefits for Detoxing, Cancer, Weight Loss & More


Chlorella benefits

Are you looking for an all-natural supplement that boosts your energy, supports fat loss and helps detox heavy metals like lead and mercury from your body? If so, a freshwater algae called chlorella may be exactly what you need.

Native to Taiwan and Japan, this superfood is rich with phytonutrients, including amino acids, chlorophyll, beta-carotene, potassium, phosphorous, biotin, magnesium and the B-complex vitamins. Chlorella’s rich green color comes from a high concentration of chlorophyll, a detoxifying plant pigment.

We are all told to eat more leafy green vegetables for good health, but sometimes it can be difficult to get the five to seven servings of vegetables a day recommended by nutritionists and doctors of functional medicine. While juicing is another option, it’s simply too time-consuming for most people. Meanwhile, most green leafy vegetables pale in comparison to the health benefits that chlorella can provide.

By consuming organic, low-temperature-extracted chlorella supplements, you can receive all of the chlorella benefits in a simple powder or tablet form.

What Is Chlorella?

Chlorella is genus of green algae (family Chlorellaceae) found either singly or clustered in fresh or salt water. The whole chlorella plant is used to make nutritional supplements and medicine.

There are several species of chlorella, with Chlorella vulgaris being one of the most commonly used in supplements. Chlorella algae is a cousin of spirulina.

Chlorella was discovered  in 1890 by the Dutch microbiologist Dr. Martinus Beijerinck using a microscope. However, it has existed for billions of years — since the beginning of planet Earth.

There are more than 2o species of chlorella, including C. vulgaris, C. ellipsoidea, C. saccharophila, C. pyrenoidosa and C. regularis.

The name “chlorella” is derived rom the Greek word “chloros,” which means green, and Latin diminutive suffix “ella,” meaning small. In the wild, it is able to reproduce rapidly through the process known as photosynthesis. All it needs to grow and multiply are water, sunlight, carbon dioxide and a small quantity of minerals.

In the 1960s, scientists realized that it was totally impossible for humans to digest chlorella in its natural state due to its tough cell walls that encapsulate its beneficial nutrients. This is again why you see chlorella supplements labeled as “cracked cell wall chlorella.”

What does chlorella do for your body? Studies have shown that chlorella benefits the entire body by supporting healthy hormonal function, promoting cardiovascular health, helping negate the effects of chemotherapy and radiation, lowering blood pressure and cholesterol, and aiding in the detoxification of our bodies.

It has also been used to try to treat or prevent the following:

Some people also take chlorella to try to:


1. Detoxifies Heavy Metals

It is important for your overall health and wellness to be proactive in detoxing heavy metals and toxins.

One of chlorella’s most significant health benefits is that it wraps itself around even stubborn toxins residing in our bodies, such as lead, cadmium, mercury and uranium, and keeps them from being reabsorbed, as shown in animal and lab studies. Regular consumption can even help keep heavy metals from accumulating in our bodies’ soft tissues and organs in the first place.

2. Detoxifies Radiation and Chemotherapy

Radiation therapy and chemotherapy are the most common forms of cancer treatment today. Anyone who has gone through either of these treatments, or knows anyone who has, knows what a toll they take on the body.

Chlorella’s high levels of chlorophyll have been shown to protect the body against ultraviolet radiation treatments while removing radioactive particles from the body.

According to researchers from Virginia Commonwealth University Medical College, “Cellular components and functions of the immune system remain at or near normal levels and are less adversely affected when patients are undergoing chemotherapy and/or taking immunosuppressive medications such as steroids”

The university’s two-year study allowed researchers to observe that glioma-positive patients have fewer respiratory infections and flu-like illnesses when taking chlorella.

3. Supports Your Immune System

Research published in the Nutrition Journal found that after eight weeks of chlorella intake, NK cell activity improved. Researchers from Yonsei University in Seoul Korea studied healthy individuals and their immune systems’ response to chlorella supplements.

The results showed that chlorella supports a healthy immune system response and helps “natural killer” cell activity.

4. Promotes Weight Loss

Losing weight is difficult, especially as we age. In a study published in the Journal of Medicinal Food, researchers state, “Chlorella intake resulted in noticeable reductions in body fat percentage, serum total cholesterol, and fasting blood glucose levels.”

Chlorella benefits arrive by helping regulate hormones, helping with metabolism, improving circulation and promoting higher levels of energy. It also helps reduce weight and body fat and removes stored toxins.

As our bodies lose weight, toxins are released and can be reabsorbed. It is important to flush these toxins out of our systems as quickly as possible. Chlorella’s ability to surround the toxins and heavy metals resident in our bodies helps facilitate elimination and prevent reabsorption.

5. Promotes Healthier Skin

Research shows that chlorella benefits for skin also exist. A study published in the journal Clinical Laboratory revealed that it reduces oxidative stress, which can be caused from pollution, stress and a poor diet.

The reason it is effective at producing healthier skin is because it naturally increases levels of vitamin A, vitamin C and glutathione in your body, which eliminate free radicals and protect your cells.

By just taking one teaspoon or a couple capsules daily of a chlorella supplement, you may see results in as little as two weeks.

6. Fights Cancer

It is believed that all human bodies at some time develop cancer cells. Properly functioning immune systems have the ability to attack and destroy these cells before they have the chance to take hold and create cancer.

An animal study found that chlorella helps fight cancer in several ways.

First, when taken pre-emptively, it can strengthen the immune system. Second, it can help remove heavy metals and toxins and make it less likely to get environmentally based cancers. Third, chlorella enhances the action of T cells that help fight new abnormal cells.

Results from another study published in 2023 “demonstrated the anti-cancer effect of Chlorella sp. ethanolic extract to promote cancer cell death via inhibition of AKT/mTOR pathway.”

Plus, as mentioned above, if cancer is diagnosed and chemotherapy or radiation therapy is used, chlorella can help to fight the side effects and be used in addition to natural cancer treatments.

7. Helps Lower Blood Sugar and Cholesterol

Type 2 diabetes and high cholesterol are two of the serious chronic conditions facing many Americans today. Years of improper eating, stress and a lack of sleep have led many to one or both of these diagnoses.

In a study published the Journal of Medicinal Food, researchers found that doses of 8,000 milligrams of chlorella per day (divided into two doses) help lower cholesterol and blood glucose levels.

Researchers observed first a decline in cholesterol levels and then the improvement in blood glucose. They believed that chlorella activates a number of genes at the cellular level that improve insulin sensitivity, encouraging a healthy balance.

A meta-analysis on the effects of chlorella supplements on cardiovascular risk factors found mostly positive effects: improving total cholesterol levels, low-density lipoprotein cholesterol levels, systolic blood pressure, diastolic blood pressure as well as fasting blood glucose levels.

However, the supplements didn’t show much of an effect for triglycerides and high-density lipoprotein cholesterol levels.

8. Boosts Energy

With its impressive mix of vitamins, minerals, antioxidants and phytonutrients, chlorella is used as a supplement and remedy by many practitioners of traditional medicine. With its high chlorophyll content, it’s often employed for inflammatory-related conditions as well as its detoxifying and renewing benefits.

In Traditional Chinese Medicine, it is said to provide yin energy. This means that it is very helpful to an overstimulated or imbalanced body. It can have a calming effect on the nervous system while nourishing and restoring the body as a whole.

In Ayurvedic Medicine, it is believed to supply ojas (“vitality” or “life force”) to people who feel run down or who could use an extra boost to their already positive state of health.

In addition, it’s been shown to help boost physical performance across various forms of exercise.

9. Protects Eye Health

Since it contains significant levels of lutein, an antioxidant known to protect the eyes, chlorella can also support vision and eye health. In fact, research published in the Journal of Food Biochemistryinvestigated whether an extract of Chlorella vulgaris (ECV) could ameliorate the negative influence of N-methyl-d-aspartate (NMDA) on the retinas of rats and decrease oxidative stress-induced cell death in transformed retinal ganglion cells (RGC-5).”

The researchers concluded: “Our results clearly demonstrate the neuroprotective effect of ECV on retinal degeneration both in vitro and in vivo.”

10. Supports Healthy Pregnancy

There are several ways in which chlorella can support a healthy pregnancy, making it a great addition to any pregnancy diet plan. For starters, it’s been found to help reduce the risk of anemia, proteinuria and edema in pregnant women. In addition, it may help lower high blood pressure that can occur during pregnancy.

Furthermore, it’s been found to be safe for pregnant women with low-grade inflammation while helping decrease constipation in pregnant women.

11. May Enhance Liver Health

A 2021 meta-analysis examined the effects of chlorella supplementation on liver health biomarkers. While the researchers note that more studies are needed to confirm the effects on healthy subjects, it certainly appears to benefit liver health in people with non-alcoholic fatty liver disease.

It’s believed to do this through “modulation of dyslipidemia, insulin resistance, and inflammatory pathways.”

There is also evidence — mostly from animal and lab research — that chlorella may help:

Nutrition Facts

The exact amount of different nutrients really depends on the supplement you use, but chlorella is unquestionably one of the most nutrient-dense superfoods on the planet. It’s low in calories yet contains a healthy dose of the following:

  • Protein
  • Vitamin C
  • Vitamin A
  • Iron
  • Vitamin B12
  • Antioxidants
  • Omega-3 fatty acids

In addition, chlorella nutrition contains a good amount of fiber, vitamin K, vitamin B1, vitamin B6, phosphorus, magnesium, zinc, copper, potassium, calcium, folic acid and other B vitamins.

When you look at its nutrient density score, it’s easy to see why it is ranked one of the top health foods in the world. In fact, it is more nutrient-dense per gram than other greens, including kale, spinach and broccoli.

Chlorella vs. Spirulina vs. Chlorophyll

Is chlorella or spirulina better? While most Americans may have not heard of chlorella, many people have been taking spirulina for years.

Chlorella and spirulina are both algaes that contain chlorophyll and offer additional nutrients. They are both waterborne organisms, but at the cellular level, they are quite different.

Spirulina is a spiral-shaped, multicelled plant with no true nucleus. It’s blue-green in hue and can grow up to 100 times the size of chlorella. Comparably, chlorella is a spherical-shaped single-celled microorganism with a nucleus and is solid green.

Chlorophyll is the green pigment found in spirulina, chlorella and all green plants. While chlorophyll is completely natural, a similar semi-synthetic mixture called chlorophyllin is made in laboratories to be used in supplements, such as those marketed as “liquid chlorophyll.” Green algae like chlorella are often used to make chlorophyllin.

Spirulina can be used and consumed in supplements right after harvest, but chlorella has to go through processing to break its cellular walls to enable the absorption of its benefits by users. Chlorophyll comes from green plants and algae. Chlorella is said to be higher in chlorophyll (maybe even double the amount) than spirulina while spirulina is typically higher in protein, iron, protein and gamma-linolenic acid.

The benefits of chlorella and spirulina are very similar because both have a concentrated balance of nutrients shown to help cleanse and detoxify the body and a high concentration of protein that supports energy and clarity. Chlorophyll’s known benefits of liver detoxification, skin protection and improved digestion are very similar, which isn’t surprising since chlorophyll is a star ingredient of both spirulina and chlorella and is behind many of their benefits.

Chlorella and spirulina nutrition both contain additional nutrients like vitamin C, vitamin A, B vitamins and more that are not contained in chlorophyll supplements. Spirulina has even been used in the World Health Organization’s feeding programs for malnourished children in undeveloped countries.

Chlorophyll, spirulina and chlorella supplements are all available in powder, tablet or liquid form. Depending upon your health goals and what other supplements you’re taking, one of these supplements may appeal to you more than the others. You can also often all three in certain super green powders.

Supplements and Dosage

You can purchase chlorella in powder, tablet or liquid form at your local health store or online. Its tough exterior cellular walls are difficult to digest. In fact, it took many years of research, study, trial and error to find a way for the human body to effectively digest it.

The substance in these walls is believed to be what surrounds heavy metals, pesticides and other toxins and helps remove them from the human body.

What is the best chlorella? When purchasing a chlorella supplement, make sure to buy “cracked cell wall chlorella” because this type is completely absorbable. You also want to look for a brand that is organic and low-temperature-extracted.

When taking a chlorella supplement, there are two main ways to consume it:

  • Smoothie — Chlorella has a very strong taste, so you will not want to add more than about half-teaspoon to a smoothie. You can use other ingredients like banana, coconut water, vanilla protein powder and lime juice to help hide the taste.
  • Tablets — Simply take a serving size with water to experience chlorella health benefits.

Risks, Side Effects and Precautions

Chlorella powder and other chlorella supplements can cause side effects in some individuals. What are the side effects of taking chlorella? Some of the chlorella side effects include:

  • swelling of the face or tongue sensitivity to sunlight
  • digestive upset
  • acne
  • fatigue
  • lethargy
  • headaches
  • vertigo
  • shaking

The majority of these side effects and symptoms are typical to any detoxification program.

Chlorella may also cause green-colored stools. Other chlorella dangers include potential allergic reactions. Seek emergency medical attention if you experience severe breathing problems or a life-threatening allergic reaction called anaphylaxis after taking it.

Chlorella supplements often contain iodine so individuals who are allergic to iodine or are watching their iodine intake should beware.

People who are being treated for a medical condition or are currently taking any type of medication should check with their doctors before taking chlorella. It is known to interact with immunosuppressant drugs as well as blood thinners like warfarin (Coumadin).

Experts have different opinions on the safety of this algae during pregnancy so pregnant and nursing women should talk to their health care providers before taking chlorella supplements.

Final Thoughts

  • Chlorella is a green algae rich in chlorophyll, just like its cousin spirulina.
  • Chlorella benefits include helping with detoxification from heavy metals and conventional cancer treatments, boosting the immune system and skin health, helping with weight loss, lowering blood sugar and cholesterol levels, and fighting cancer.
  • It’s also commonly used as a natural remedy for boosting energy and mental function.
  • Chlorella powder and spirulina powder can both be easily be added to any smoothie recipe. They can also be used in soups, desserts and more!

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