Spirulina Vs. Chlorella: What’s the Difference?

By Dr. Livingood
May 21, 2021

In the supplement world, you’ll find shakes, smoothies, and pills with active ingredients that can provide numerous health benefits. Of all the active ingredients you can find in the modern market, spirulina and chlorella are commonly cited as important algae supplementary ingredients, especially since they are so similar.

In fact, spirulina and chlorella are so similar that many people don’t know the differences between these two algae. But there are some important differences you should be aware of when choosing a supplement to make sure that your body gets the right vitamins and minerals (as well as the right protein content) in your morning supplement shake or smoothie.

Let’s take a closer look at both spirulina and chlorella and see which might be right for your wellness regimen.

What is Spirulina?

Spirulina is a blue-green algae that’s found in a wide range of health supplements. Although it seems like a recent fitness trend ingredient, the ancient Aztec civilization may have consumed spirulina historically for its supposed health benefits.

These days, spirulina supplements are made from two other kinds of microalgae: Arthrospira platensis or Arthrospira maxima. It’s a very common supplement ingredient in health or fitness smoothies, usually as a greens powder.

What is Chlorella?

Chlorella is another nutrient-dense algae species, although it is a green algae rather than a blue-green variety. This freshwater algae comes in over 30 unique types, although the two most commonly used in supplements are chlorella vulgaris and chlorella pyrenoidosa.

Chlorella has to be taken as a supplement – humans cannot digest it as a regular food because of its high fiber content and very sturdy cellular walls. As a result, chlorella supplements typically come as capsules, extracts, green powder supplements, and more, all of which have the algae’s cell walls already broken down before consumption.

Benefits of Spirulina

Both spirulina and chlorella can provide your body with a number of key benefits. But spirulina has some notable advantages over its counterpart.

1. Higher Protein Content

For one, spirulina is a complete protein source in that it includes every essential amino acid. This higher protein content makes spirulina a particularly good supplementary choice for vegans, who don’t always have full protein sources in their diets due to their focus on plant-based food products.

In fact, a single tablespoon of spirulina has 4 g of protein, plus just 20 cal. This makes it a fantastic protein source for any dietary lifestyle.

2. More Antioxidants

For another, spirulina is thought to have higher than average antioxidant content, especially compared to chlorella. Antioxidants are valuable compounds that can trap free radical oxygen molecules and decrease them from damaging other cells throughout your body.

There’s even a study that shows that spirulina has more phenol and antioxidant content compared to chlorella.

Benefits of Chlorella

Chlorella is also a great supplement to target as opposed to spirulina for a few distinct reasons.

1. Higher Omega-3 Fatty Acid Content

Omega-3 fatty acids are commonly found in plants and are necessary for protein synthesis and other key bodily functions. Chlorella has higher than average omega-3 fatty acid content compared to spirulina.

There are three types of omega-3 fatty acids in total: EPA, DHA, and ALA. Chlorella has plenty of both EPA and DHA.

2. More Calories

Chlorella also has more calories compared to spirulina on a gram-to-gram basis. For example, a single tablespoon of chlorella has 36 cal compared to the 20 you’d get from a single tablespoon of spirulina.

How are Spirulina and Chlorella Similar?

Although there are a few key differences between both algae supplements, it’s important to recognize that they are both more alike than they are different.

They share a number of major advantages, including:

Highly Nutritious. They are both very good sources of vitamins, such as vitamin A, vitamin B, and beta-carotene
Weight Loss. Spirulina in particular may be able to help various individuals lose weight or improve their BMI
Regulate Blood Sugar Which makes them great supplement choices for folks with certain health conditions. Specifically, chlorella can improve glycemic status by boosting insulin and blood glucose levels whereas spirulina can help to manage blood glucose levels.
Supporting Heart Health. Spirulina can lower LDL cholesterol and triglycerides, as well as potentially lower high blood pressure. Additionally, you can supplement daily with spirulina to reduce blood pressure and lower high cholesterol

As you can see, both supplements are advantageous choices because of their myriad benefits.

Is Spirulina or Chlorella?

Better is a subjective term that depends on what you need assistance with and which of the two will go best with your supplement routine.

If you tend to drink highly nutritious smoothies or other liquid supplements, spirulina will be easily absorbed and might be a better choice, especially if you are a vegan. Remember, spirulina has tons of protein: it’s a complete protein source and can help shore up some of the weaknesses of a vegan lifestyle.

In contrast, chlorella offers more calories and greater omega-3 fatty acid content. You’ll commonly find chlorella supplements in tablet or capsule forms, which may make these algae a better choice if you prefer taking your supplements like that (such as with breakfast or another meal).

However, we’d recommend considering taking both spirulina and chlorella where possible. It’s clear that both of these algae provide several overall health benefits for those who consume them regularly. While they can’t fully replace other fruits and vegetables (and other key parts of a balanced diet), they can help you achieve your holistic wellness goals more readily and easily in many ways.

Speak to your dietitian about which of the two algae species may be a better supplementary choice for your unique needs, and check out our health guides for more information about supplements and whole-body wellness.