Chlorella Benefits & Uses (and When It Can Be Dangerous)

Is Chlorella a Superfood

I’ve raved about Spirulina before and shared how I use it, but Spiulina’s cousin Chlorella is a powerhouse as well.

What is Chlorella?

Like Spirulina, it is a freshwater algae with a host of benefits. Unlike spirulina, it is a single-celled fresh water algae (spirulina is multi-cell). It is also one of the oldest known species on the planet and that has the unique ability to reproduce 8 times a day, making it a sustainable nutrient source.

Chlorella has a very hard outer shell, making it almost completely indigestible to humans, so supplemental forms undergo a special process that cracks this outer shell for enhanced digestibility.

It is one of the most-used supplements in Japan (where most of the world’s supply is produced).

Chlorella Nutrition Facts:

Many sources list this nutrient dense algae as one of the most nutrient dense foods in the world, claiming that:

A 1-ounce (3 tbsp) serving of chlorella contains:

  • Protein—16g
  • Vitamin A—287% RDA
  • Vitamin B2—71% RDA
  • Vitamin B3—33% RDA
  • Iron—202% RDA
  • Magnesium—22% >RDA
  • Zinc—133% RDA

While this is true, it would not be cost effective to consume this much daily and doing so might lead to unwanted side effects. Sources that cite that it is more nutrient dense gram for gram than other greens like broccoli and kale are technically correct. It is just much less expensive and more realistic to consume these amounts of broccoli and other greens.

Additionally, since this algae has to undergo a specialized treatment to break down its cellular walls to make it digestible to humans, it is typically more costly than other sources of these nutrients.

It certainly can be beneficial, but it isn’t going to replace a salad or other greens in your daily life.

Chlorella Benefits

Though it may not be a realistic source of nutrients due to its high cost, there may still be some reasons to take this micro-algae.


Chlorella is a source of Chlorophyll, Protein, Iron, Magnesium, and amino acids, but it is primarily known as a detoxifying supplement. Its tiny size and unique properties make it able to bind to heavy metals and unwanted chemicals in the body.

There is some debate about its safety for detoxification, however, as it may remove heavy metals but not bind strongly enough to remove them. This means it may actually increase the heavy metal levels moving around in the body.

It is often used by those undergoing chemotherapy or radiation to help reduce the body’s chemical load, and it is said to support the body’s liver and detoxification pathways without stripping beneficial minerals from the body.

The most studied use for Chlorella in detoxification is in taking small amounts over time to help avoid heavy metal build up in the body. This study showed that it may have a protective effect for mice exposed to lead and other heavy metals.

Important: Anyone who has been exposed to any type of heavy metal should work with a doctor or practitioner who specializes in removal. Removing metals to quickly or with the wrong substances can actually make things worse!

Immune Support

WebMD lists that Chlorella is used to boost the immune system, to aid digestive problems, to increase good bacteria in the digestive system, and for ulcers.

A double-blind placebo study found that regular use increases natural killer cell activity and early inflammatory response. The study reported:

These results may suggest a beneficial immunostimulatory effect of short-term Chlorella supplementation which enhances the NK cell activity and produces interferon-? and interleukin-12 as well as interleukin-1?, the Th-1 cell-induced cytokines in healthy people.

It is important to note that the study only looked at short-term effects and that we don’t know the long-term immune implications. Also, as it does affect the immune system, those with any type of immune problem or autoimmune disease should work with a doctor when taking this or any other immune-stimulating substance.

There is anecdotal evidence that it may help reduce hypertension and cholesterol, increase energy, to reduce asthma attacks and PMS and for relief for those with fibromyalgia.

Difference Between Chlorella and Spirulina

Though they look, smell and even taste similar, there are few key differences:

  • Structure: Both are types of algae, but Chlorella is a true single-cell algae with a nucleus, while Spirulina is a multi-celled plant with no distinctive nucleus. For this reason, spirulina is much larger than chlorella.
  • Color: Spirulina is a cyanobacteria, a blue-green type of algae, while Chlorella is a green algae.
  • Amount of Nucleic Acids: Both are a good source of nucleic acids, though Chlorella has almost twice as much as Spirulina. Nucleic acids are important factors for DNA and RNA in the body.
  • Digestibility: Spirulina can be consumed easily after harvest while Chlorella has to go through a process to break its cell walls before the body can use it.
  • Chlorophyll Content: Chlorella is higher in Chlorophyll, with almost double the amount.
  • Iron, Protein and GLA: Spirulina is higher in Iron, protein and beneficial Gamma-Linolenic Acid (GLA).
  • Heavy Metals: Chlorella has unique properties in its cell walls that make it bind to heavy metals and other contaminants (spirulina does not have this same benefit).


Though generally considered safe, Chlorella comes with some cautions and warnings. It can contain moderate levels of iodine, so those with iodine sensitive thyroid conditions or iodine allergies should avoid it. Those with auto-immune disease should consult with a doctor first as it can increase immune function and may make these conditions worse.

Sources are divided on safety during pregnancy, so pregnant and nursing women should talk to their individual doctors and midwives to evaluate if these supplements would be safe or beneficial for them.

Additionally it can cause a detoxifying effect in some people, and those sensitive to certain types of mold should avoid it as well. Due to its high Vitamin K content, it will increase clotting, so those with clotting disorder should avoid it as well. A great source of iron, it should be used in moderation by men and post-menopausal women.

Finding Quality Chlorella

It is important to find a quality Chlorella supplement as low-quality supplements may contain mercury or not have a cracked cell wall, making them useless to the body. Due to the detoxifying effect, it is also important to start slowly and consult a doctor before using if any health condition is present.

Personally, I have used these brands with good results:

  • Recovery Bits: Made from 100% organically grown, Non-GMO chlorella, an algae containing 40 nutrients, antioxidants and chlorophyll. Use code “wellnessmama” for 20% off.
  • Chlorella Powder: Good quality powder, but the taste can be tough for some people.
  • Capsules: High quality, from Japan.
  • Chlorella/Spirulina Blend Tablets: High quality blend and good value.

Ever used Chlorella? What was your experience?

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