Is Chlorella Good For The Immune System?

is chlorella good for immune system

Article at a glance:

  • Several studies show the positive effects of chlorella on the immune system.
  • Chlorella can make the body more resistant to infections and diseases.
  • Chlorella’s components have proven immune-boosting benefits.


With so many threats to our health today, more and more people are looking for natural ways to boost their immunity. As microalgae supplements like chlorella continue to gain popularity, it begs the question: Is chlorella good for the immune system?


Does Chlorella Boost the Immune System?


Chlorella is a freshwater blue-green algae known for many amazing health benefits — one of which is chlorella’s ability to boost the immune system. According to scientific and nutrition journal studies, chlorella immune system benefits include:


Enhance Natural Killer Cell Activity



Short-term chlorella supplementation was found to have a beneficial immunostimulatory effect on healthy individuals.

In this study, participants were given 5 grams of chlorella tablets for 8 weeks. Results showed the chlorella group had enhanced natural killer cell activity compared to the control group. The chlorella group also had increased levels of serum cytokines — specifically interferon-γ, interleukin-1β, and interleukin-12, which are essential for the Th-1 immune responses. Cytokines are small proteins that control the activity and growth of blood and immune system cells.

A similar study found that chlorella pyrenoidosa extract (CPE) stimulated cytokine production in the peripheral blood mononuclear cells (PMBC) of healthy humans. The PMBCs were treated with 1, 10, and 100 mg/mL of CPE for 24 hours.

Results showed increased interleukin 10 (IL-10), an anti-inflammatory cytokine. There was also a strong stimulation of interferon-gamma (IFN-γ) and tumor necrosis factor-alpha (TNF-α), both crucial for innate and adaptive immunity. They help stimulate the early inflammatory response of cells during infections.


Improved Mucosal Immunity


Chlorella supplementation may also help enhance mucosal immunity, the first line of defense against pathogens that cause respiratory tract infections. This is by enhancing or maintaining our salivary secretory immunoglobulin A (SIgA) levels.

In one study, female athletes ingested chlorella pyrenoidosa powder in tablet form (30 pcs. or 200 mg in total) for 4 weeks. Participants then attended a training camp with two sessions per day. Based on the analysis of saliva samples, those in the chlorella supplementation group had no difference in salivary SIgA concentrations before and during the training camp. In contrast, those in the control group were observed to have decreased SIgA secretion rates.

Meanwhile, in another study, men were given 30 tablets of a chlorella-derived multicomponent supplement daily for 4 weeks. Following a 12-week washout period, participants in the chlorella treatment group were found to have increased salivary SIgA secretion — which may point to improved mucosal immune function.


Does Chlorella Affect the Immune System?


By strengthening the immune response, chlorella may help protect the body from bacterial, fungal, and viral infections. It may also help fight cancer, reduce tumor growth, and reduce the risk of serious health issues and chronic diseases.


1. Fights Infections


In one animal study, 2 mg/kg of chlorella vulgaris extract was administered 1, 4, and 7 days before E. coli infection. Results showed that mice in the chlorella group had enhanced resistance against E. coli infection compared to the control group. The chlorella group was also observed to eliminate bacteria 6 hours after treatment.

Similarly, hot water extract of chlorella pyrenoidosa was administered to mice every other day for 10 days before cancer or leukemia cell transplantation. Those in the chlorella group had a 73.3 to 80% survival rate after 60 days. All mice in the control group perished after 20 days.

According to researchers, chlorella may promote cytotoxic activities against tumor cells by promoting the host immune response.

2. Reduce Tumor Growth


These immune system benefits of chlorella can also be observed in human participants. In one study, immunocompromised patients with a history of glioma were given chlorella as adjunctive therapy. They took 20 g of chlorella tablets and 150 mL of chlorella extract daily for 2 years. Patients were monitored for 2 years, with blood tests performed every 3-4 months.

According to the results, chlorella intake did not significantly impact survival rates. However, those in the chlorella treatment group had a near-normal immune function. They were also observed to have near-normal levels of lymphocytes, natural killer cells, and neutrophils.

Researchers noted that the chlorella group was less affected than patients undergoing chemotherapy and taking immunosuppressive medications. Over the course of the study, these participants also had fewer cases of respiratory infections and flu-like symptoms.


3. Improve Immunity to Respiratory and Chronic Diseases



Chlorella supplements may also help manage the clinical symptoms of respiratory diseases. According to a study, chlorella’s ability to improve immunity may help attenuate the oxidative stress and chronic inflammation of asthma and chronic obstructive pulmonary diseases.

In this study, participants took 2,700 mg of chlorella vulgaris daily alongside their conventional treatment regimen. After 8 weeks, they experienced less coughing, wheezing, shortness of breath, and sputum. The chlorella group saw the most improvement in wheezing and sputum compared to the placebo group.

Researchers also found that chlorella may help increase aerobic endurance capacity. This was observed after athletes took 15 chlorella tablets twice a day for 4 weeks. There was an increase in peak oxygen uptake during exercise compared to the placebo group.

Increased aerobic endurance capacity may not only support immunity following physical activity, but it may also provide short-term improvements in immune and respiratory function during COVID-19 infections.


How Does Chlorella Boost the Immune System?


More clinical research is needed to understand chlorella’s beneficial immunostimulatory effect. However, by looking at the nutritional profile of chlorella, we may begin to understand how chlorella can boost the immune system and confer other amazing health benefits.

Chlorella is naturally rich in vitamins, minerals, and other nutrients. This includes B vitamins and vitamin D, which are only found in a few plant sources. Chlorella is also packed with minerals, essential amino acids, antioxidants, and polyunsaturated fatty acids. It is also a complete protein with dietary fiber.

Chlorella’s nutrient-dense profile helps promote our overall health. By keeping the body well-nourished, different systems can function optimally. For the immune system, cells can do their join in protecting against disease-causing invaders.

Researchers have noted certain components that may be responsible for chlorella’s immune-boosting benefits. These include:


Polyunsaturated Fatty Acids


Chlorella is rich in polyunsaturated fatty acids (PUFAs), including alpha-linolenic acid (ALA) — which is the precursor of docosahexaenoic acid (DHA) and eicosatetraenoic acid (EPA).

DHA and EPA are known to have a strong immunomodulatory effect. These PUFAs ensure that the immune system reacts appropriately to pathogens. This is by enhancing the function of B cells and other immune cells; promoting the production of cytokines and chemokines, and inhibiting the pro-inflammatory response after infection.




Polysaccharides in chlorella also help enhance immune function. In particular, chlorella is rich in β-1,3-glucan, which can modulate both the innate and adaptive immune response.

According to studies, beta-glucans help stimulate natural killer cell receptors, trigger a group of immune cells, and enhance phagocytosis (destruction of viruses and infected cells).




Chlorella has a rich antioxidant status due to the presence of beta-carotene, lutein, and other carotenoids. Other nutrients in chlorella — such as chlorophyll, polysaccharides, and amino acids — also exhibit antioxidant activity.

By helping decrease oxidative damage and inflammation, antioxidants chlorella can help protect the integrity of the immune system. Chlorella consumption can increase the activation of immune cells to better protect against pathogens.

Studies show that antioxidants can enhance immune function, which helps lower the risk of chronic diseases such as hypertension.


Amino Acids


Studies show that a deficiency in amino acids is associated with impaired immune function.

Thankfully, chlorella contains all nine essential amino acids and nine non-essential amino acids. In particular, chlorella has a significant amount of arginine — an essential nutrient for both innate and adaptive immunity.

Arginine plays an important role in many immune functions, most notably the synthesis of nitric oxide that helps kill viruses, bacteria, and other pathogens.




Chlorella contains vitamins A, B, C, and E, which are known for maintaining the immune system.

Vitamin A stimulates the production of white blood cells and strengthens mucosal epithelial barriers to better protect against pathogens. Meanwhile, vitamin C is known to stimulate phagocytes, enhance the production of interferons, and promote the maturation of T cells.

Vitamin E is also essential for immunity as it assists with T cell production and modulates T cell function. Meanwhile, B complex vitamins help regulate immune cells for a healthy immune system.




Chlorella’s nutritional benefits can be likewise attributed to its mineral content, particularly immune-boosting minerals such as iron, zinc, and selenium.

These minerals promote the normal development and maturation of immune cells. Selenium also helps oxidative stress that can damage the integrity of immune cells.

Deficiencies in these minerals have been associated with increased susceptibility to infectious diseases. Supplementing with chlorella can also address iron-deficiency anemia, which is common during pregnancy or among those who primarily eat a plant-based diet.


Other Health Benefits of Chlorella



Apart from boosting your immune system, potential health benefits of chlorella include:

  • Heart Health: Chlorella helps reduce high blood pressure and keeps blood vessels flexible to lower the risk of heart disease.
  • Eye Health: Lutein in chlorella helps protect against age-related eye diseases such as macular degeneration.
  • Brain Health: Chlorella may help inhibit cognitive decline associated with neurodegenerative diseases like Alzheimer’s.
  • Circulatory Health: Chlorella helps lower blood glucose levels and improve insulin sensitivity.
  • Respiratory Health: Chlorella helps enhance oxygen production, which boosts energy levels and metabolic processes that can aid in weight loss.
  • Gut Health: Chlorella helps support healthy bacteria in the gut and regulates key digestive functions.

There are many other chlorella benefits. And with more research ongoing, we may also discover more potential health benefits of chlorella in the coming years.


Taking Chlorella for Immune System Boost + Other Health Benefits


At this point, taking chlorella powder for an immune system boost and other health benefits seems like a no-brainer. Numerous studies show that chlorella contains essential nutrients that our body needs to stay healthy. As long as we nourish our bodies, we can also reduce the risk of chronic health issues and diseases.

Just remember that when taking chlorella supplements, choose wisely. Don’t just choose the one that’s the most available in health food stores. Choosing a chlorella supplement that has undergone proper and certified quality control practices is better. For instance, Taiwan-sourced chlorella has strict guidelines for cultivating, harvesting and processing chlorella powder.

This ensures that you get that immune system boost and other health benefits. Once you’ve made your choice, you can take your chlorella dietary supplement as is or incorporate it into tasty, healthy recipes!


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John Riedl

Simply put that’s why I’ve gone down the health journey of research and creating health brands.

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