February 01, 2021

Chlorella vs Spirulina: What's the Difference?

Chlorella and spirulina are often grouped together interchangeably. However, there are certain differences when it comes to discussing the benefits of chlorella vs spirulina.

Differences between chlorella and spirulina

The differences involve color, where each grows, nutritional value, and how each is digested. First is the visual difference. Chlorella has a bright green appearance due to the amount of chlorophyll it contains, while spirulina is a blue-green algae. 

Second, chlorella is largely considered freshwater algae, and spirulina can be found in both freshwater and saltwater, although most commonly found in the latter. Nutrient-wise, both superfoods are high in protein and essential daily vitamins and low in fat and calories. A 28-gram serving of chlorella has significantly higher amounts of zinc (133 daily value percentage), iron (202 daily value percentage), and vitamin A (287 daily value percentage) compared to spirulina.1 Conversely, spirulina contains high amounts of B1, B2, and copper.2

Each carries a high nutritional value on their own yet are more effective when taken together. Although used for centuries among Aztec and Asian cultures, among others, the value of chlorella and spirulina has also been confirmed by NASA astronauts who have come to rely on these algae for nutrition when exploring space. It’s a sustainable, plant-based way to prevent vitamin-deficiency. 

They are used as food supplements as part of a balanced diet due to their nutritional value and how well they generate oxygen and remove carbon dioxide. Spirulina lacks a cellulose cell wall which makes it easier to digest. However, since both are available in powder or chlorella supplement or spirulina supplement form, it makes both similarly digestible. Each is touted for its individual benefits, but they both largely promote good health in similar ways. 

What Does Chlorella Do?

Chlorella is often referred to as a natural detoxifier. It’s been known to reduce heavy metals and harmful chemicals in the body that become built up through the foods we eat, products we use, and the environment. A study conducted by researchers in Spain concluded chlorella supplementation enhanced detoxification of heavy metals, including lead, silver, and mercury, after taking it for 90 days.3 Another study published by the Society of Environmental Toxicology and Chemistry provides evidence that chlorella was able to remove bisphenol A (BPA), an endocrine disruptor commonly found in plastic materials from landfills, decreasing the amount of toxins in the air.4

Chlorella Contains Higher Levels of Omega-3s

Both chlorella and spirulina have similar amounts of fat; however, their types of fat are very different. First, omega 3 fatty acids are associated with many health benefits, such as reducing inflammation, lowering risk of heart disease, improving bone health, and lessening the risk of cancer. Typically, people only consume small portions of omega-3 fatty acids and don't actually meet their daily needs. A study found that chlorella contains more omega-3s, while spirulina contains more omega-6s.



What Does Spirulina Do?

Now that you know what chlorella does, you may be wondering, “what is spirulina and how is it different from chlorella?” When comparing chlorella vs spirulina, spirulina is higher in B1 (thiamine) which leads to higher energy levels. One of the many Vitamin B1 benefits is that it helps the body convert food into energy. A lack of it results in tiredness and muscle weakness. Vitamin B1 supports brain functioning, including memory improvement and concentration, as well as improving reaction times. Spirulina also enables the production of vitamin B6 that helps with energy release and can aid in weight loss. A study performed by the Universidad Autónoma de Chihuahua in Ciudad Juarez confirmed spirulina supplementation enhanced the effects of systematic exercise in overweight, but mostly obese, individuals that took part in the trial.5 It helped improve the participants’ general fitness markers, which were measured by a higher maximal oxygen intake, better anaerobic threshold, and an overall improvement of resting heart rate. 

Although these are a few notable differences of what each algae is best known for, when talking about chlorella vs spirulina, they are more alike than different. Individually and together, they offer a range of health benefits. 

Spirulina May be Higher in Protein

The protein that is found in both chlorella and spirulina contains all essential amino acids, which your body can absorb quite easily. Studies indicate that spirulina can contain 10% more protein than chlorella. While spirulina may be higher in protein, chlorella is

Health Benefits Shared by Chlorella and Spirulina

Now that we have shared what these two algae are, you may be wondering, “what is chlorella good for vs what is spirulina good for? And how can we use these two sea plants in conjunction with each other to benefit the most?” When taken as plant-based supplements, the effects of chlorella and spirulina are expansive. There has been research that has shown many chlorella benefits and spirulina benefits such as evidence in their ability to lower blood sugar, protect heart health, reduce cholesterol, and many other health-related advantages. 

Delivers Powerful Antioxidants

Both algae include antioxidant properties, including chlorophyll, beta-carotene, and several other vitamins and minerals. These are valuable in protecting overall health and help to fight against free radicals that lead to chronic disease. Antioxidants are largely found in plant-based foods, which is why a diet rich in fruits and vegetables is essential for good health. By taking a dietary supplement with chlorella and/or spirulina as the main ingredient, you can achieve this same nutritional value if you’re not meeting your daily individual servings. 

Lowers Blood Sugar

Both chlorella and spirulina may help lower blood sugar levels. Research conducted by the Sun Chlorella Corporation in Kyoto, Japan found chlorella intake over a 16-week period resulted in a noticeable reduction in blood glucose levels.6 This was in addition to lowered body fat percentage and serum total cholesterol among its test group of both healthy subjects and subjects with high-risk factors for lifestyle-related diseases. 

Furthermore, research conducted by the M S University of Baroda in India found that after two months of taking two grams of spirulina per day, participants with type 2 diabetes reported a reduction in blood sugar levels.7  (For reference, a single tablespoon serving of spirulina is usually six to seven grams.) The study also showed evidence of a significant reduction of HbA(1c) level, which indicated improvements in long-term glucose regulation.

Slows Decline of Cognitive Function

As a superfood for the body, chlorella reduces oxidative stress and has the potential to significantly slow the decline of cognitive functions associated with aging, per research conducted at the Teagasc Food Research Centre Moorepark in Cork, Ireland.8 This is partly due to the amount of healthy fatty acids both chlorella and spirulina contain. The essential fatty acids found in these algae help to reduce neuroinflammation that leads to degeneration resulting in Parkinson’s or Alzheimer’s disease. 

Alleviates Inflammation 

Healthy fatty acids also help to reduce inflammation in the body, which is especially helpful for those who suffer from chronic inflammatory illnesses. An increased dietary intake of essential fatty acids through chlorella and/or spirulina supplements can reduce inflammation in the body. Studies have shown phycocyanin found in spirulina is what offers anti-inflammatory and neuroprotective effects. Similarly, the vitamins and minerals found in chlorella also help to protect against oxidative stress and reduce inflammation that leads to chronic disease, including cancer.

Reduces Cholesterol Levels

Evidence gathered by researchers from Liverpool University Hospitals in Liverpool, UK, Hippocrateio Hospital in Thessaloniki, Greece, and University of Ioannina in Ioannina, Greece also shows the effects of spirulina in reducing high-density lipoprotein cholesterol following an eight-week treatment program, as well as reducing blood cholesterol and triglycerides in ischemic heart disease patients. 

Evidence collected from the Medical College of Virginia in Richmond, VA confirms these effects. In its study of fifty-five individuals with fibromyalgia, hypertension, or ulcerative colitis, results showed a decrease in lower serum cholesterol levels as well as a reduction in blood pressure and improvement in immune function due to chlorella intake.9  Each subject consumed 10 grams of chlorella in tablet form and a 100 mL of chlorella extract on a daily basis for two or three months. Overall, patients reported a better quality of life and normalized body functions. 

Protects the Immune System

Research conducted by the Osaka Medical Center for Cancer and Cardiovascular Diseases in Japan has shown how spirulina positively impacts the immune system by enhancing natural killer cell activity in more than 50 percent of the test subjects.10 It also showed evidence that indicated spirulina directly acts on myeloid lineages that advances the maturation stage of monocytes/macrophages. These indicate the presence of chronic conditions, including cancer, when found in high levels.

How to Incorporate Chlorella and Spirulina Into Your Diet

The importance of following a healthy nutritional plan is nothing new, but evidence regarding the benefits of spirulina, chlorella, and other functional foods have become more prolific. These algae go beyond their high nutritional value and provide health benefits that can mitigate some of the most common symptoms that arise and plague people on a regular basis. 

When considering the differences between chlorella vs spirulina, one does not necessarily rise above the other as the “better” algae. It depends on how you want to use the superfood for your health. Chlorella and spirulina have been available and used in plenty for centuries and can be found most regularly in powder, liquid, or dietary supplement forms. They are often found together on a list of ingredients to create a stronger impact. The availability makes it easy to get your essential vitamins and nutrients from a single source. 

What you consume makes a difference in how well your body and mind are able to function. It can be challenging to get the recommended daily allowance through diet alone on a consistent basis. It requires finding the right balance of fruits, vegetables, healthy fats, and proteins. Furthermore, knowing how your body interacts and processes different foods changes their effectiveness. Taking a daily supplement with chlorella and spirulina helps boost your current diet and ensures you are receiving the right combination of nutrients. Plus, these algae provide a rich source of protein, often lacking in vegetarian or vegan diets.

Overall, chlorella and spirulina have proven time and time again their nutritional, sustainable value is beneficial in multiple ways. Nourish your body with a natural, plant-based solution like GEM to prevent vitamin-deficiency, boost your health, and see how they can make a positive difference in your everyday life. 


1. Cheri Bantilan, “Chlorella vs. Spirulina: What’s the Difference? - Healthline,” Healthline, July 15, 2020, https://www.healthline.com/nutrition/chlorella-spirulina

2. Cheri Bantilan, “Chlorella vs. Spirulina: What’s the Difference? - Healthline,” Healthline, July 15, 2020, https://www.healthline.com/nutrition/chlorella-spirulina

3. José Joaquín Merino et al., “The Long-Term Algae Extract (Chlorella and Fucus Sp) and Aminosulphurate Supplementation Modulate SOD-1 Activity and Decrease Heavy Metals (Hg++, Sn) Levels in Patients with Long-Term Dental Titanium Implants and Amalgam Fillings Restorations,” Antioxidants (Basel, Switzerland) (MDPI, April 16, 2019), https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6523211/

4. José Joaquín Merino et al., “The Long-Term Algae Extract (Chlorella and Fucus Sp) and Aminosulphurate Supplementation Modulate SOD-1 Activity and Decrease Heavy Metals (Hg++, Sn) Levels in Patients with Long-Term Dental Titanium Implants and Amalgam Fillings Restorations,” Antioxidants (Basel, Switzerland) (MDPI, April 16, 2019), https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6523211/

5. Marco Antonio Hernández-Lepe et al., “Effect of Arthrospira (Spirulina) Maxima Supplementation and a Systematic Physical Exercise Program on the Body Composition and Cardiorespiratory Fitness of Overweight or Obese Subjects: A Double-Blind, Randomized, and Crossover Controlled Trial,” Marine drugs (U.S. National Library of Medicine), accessed January 21, 2021, https://pubmed.ncbi.nlm.nih.gov/30275428/.

6. Toru Mizoguchi et al., “Nutrigenomic Studies of Effects of Chlorella on Subjects with High-Risk Factors for Lifestyle-Related Disease,” Journal of medicinal food (U.S. National Library of Medicine, n.d.), https://pubmed.ncbi.nlm.nih.gov/18800884/

7. Panam Parikh, Uma Iyer, and Uliyar Mani, “Role of Spirulina in the Control of Glycemia and Lipidemia in Type 2 Diabetes Mellitus,” Journal of medicinal food (U.S. National Library of Medicine, n.d.), https://pubmed.ncbi.nlm.nih.gov/12639401/

8. Panam Parikh, Uma Iyer, and Uliyar Mani, “Role of Spirulina in the Control of Glycemia and Lipidemia in Type 2 Diabetes Mellitus,” Journal of medicinal food (U.S. National Library of Medicine, n.d.), https://pubmed.ncbi.nlm.nih.gov/12639401/

9. Panam Parikh, Uma Iyer, and Uliyar Mani, “Role of Spirulina in the Control of Glycemia and Lipidemia in Type 2 Diabetes Mellitus,” Journal of medicinal food (U.S. National Library of Medicine, n.d.), https://pubmed.ncbi.nlm.nih.gov/12639401/.

10. Tomohiro Hirahashi et al., “Activation of the Human Innate Immune System by Spirulina: Augmentation of Interferon Production and NK Cytotoxicity by Oral Administration of Hot Water Extract of Spirulina Platensis,” International immunopharmacology (U.S. National Library of Medicine, n.d.), https://pubmed.ncbi.nlm.nih.gov/11962722/.

11. https://www.healthline.com/nutrition/chlorella-spirulina


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