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Stop Getting Sick: The Benefits of Chlorella

Stay In The Game: The Benefits of Chlorella

Written by
December 8, 2017
Updated May 15, 2020

Stop Getting Sick: The Benefits of Chlorella

Chlorella contains all nine essential amino acids, making it a complete protein and, therefore, a rare find in the plant kingdom.

When you hear “winter,” what do you think of?

For some, it’s Christmas trees, snowflakes, and skiing. For others it’s vacations to places with warmer climates.

But one thought echoes in the back of all our minds: stay healthy.

Getting run down isn’t fun for anybody, but for active people who have goals in the gym, play sports, or live to be outdoors, they can feel as bad as a breakup, stock market crash, and natural disaster all rolled into one.

Being under the weather means lost progress and generally feeling weak, tired, and crappy—the opposite of our normal selves.

You’re probably already doing a number of things that help reduce your risk this winter, such as eating healthy and washing your hands frequently, but you could be doing more.

Supplementing with greens, particularly the algae chlorella, could make the difference between reaching the spring ahead of where you are now and playing catch-up till summertime.

Read on for a complete guide to chlorella, a superfood with nutrition enough to plug some key holes in your diet and keep you in the game all four seasons.

What is Chlorella?

Chlorella is a kind of algae that grows in fresh water. It gets its name (pronounced “clore-ella,” not to be confused with “Cruella” or “cholera”) from its high chlorophyll content. The lifeblood of plants, chlorophyll is the pigment that makes them green and is known to have immune-boosting properties for humans.

While an obscure food to most, chlorella is popular among vegans for its protein, B vitamins, and iron—nutrients that can be challenging to obtain enough of from plant foods alone.

Benefits of Chlorella

Stop Getting Sick: The Benefits of Chlorella

Chlorella is usually consumed as a supplement for the following reasons.

Immune System Support

A 2012 study in Nutrition Journal showed that healthy individuals who supplemented with chlorella for eight weeks had a boost in markers of immune activity. Another trial found that only four weeks of chlorella use promoted antibody expression. Antibodies are proteins that the immune system uses to neutralize bacteria and viruses that cause disease.

It’s not clear by what mechanism chlorella positively impacts immune function, but its rich nutrient profile may deserve the credit.

Huge Micronutrition

Plant foods aren’t typically great sources of bioavailable B vitamins or iron, but chlorella is a powerful exception. When measurement units are equated, it has more of each than even beef liver—one of the richest vitamin and mineral sources of all foods. Per 100 grams (about a half cup of chlorella and a serving of beef liver), chlorella has almost one and a half times as much vitamin B6, almost twice as much B2 (riboflavin), and eight and a half times as much B1 (thiamin). As for iron, chlorella boasts 20 times more than a serving of liver. For those who don’t consume animal products, chlorella has dramatically more iron than the most popular plant sources—36 times as much as soybeans and 48 times what’s in spinach.

B vitamins, if you weren’t sure, are essential for energy production in the cells, and normal nervous system function. Meanwhile, iron is necessary for hemoglobin and myoglobin, molecules that transport oxygen from the blood to lungs and muscles, respectively.

If that’s not enough, a half-cup of chlorella has more than 1000% of your Daily Value of Vitamin A (based on a 2,000-calorie diet).

More Protein

Chlorella contains all nine essential amino acids, making it a complete protein and, therefore, a rare find in the plant kingdom. The exact amount of protein in a serving of chlorella depends on how the algae was processed, but there can be as many as 5 grams in two teaspoons of chlorella powder. Interestingly, chlorella’s protein is relatively high in leucine, which is a branched-chain amino acid (BCAA) and the most important amino for muscle growth, as it turns on anabolic signaling in the body.

Cellular Health

Oxidative stress is one of the main reasons smoking is so dangerous for the body. A 2013 study in Clinical Laboratory had smokers take a chlorella supplement for six weeks and noted a significant boost in concentrations of antioxidants, including vitamins C and E. The researchers concluded that chlorella could boost the body’s ability to resist cellular damage.

Cleansing Toxins

Spirulina is another popular algae supplement that offers similar nutrition to chlorella. It’s been shown to help lower levels of arsenic in the body. There isn’t research yet to say that chlorella can do the same, at least not in humans, but there have been studies in animals that show chlorella has the potential to cleanse living cells of heavy metals. In 2011, the Journal of Toxicological Sciences found that chlorella supplementation in mice helped regulate mercury levels after 21 days versus a control group.

Chlorella vs. Spirulina

Stop Getting Sick: The Benefits of Chlorella

Those who supplement with chlorella often take an interest in spirulina too. A very similar algae product, spirulina offers complete protein as well and a wide range of vitamins and minerals that complement what you get (and don’t) from chlorella. Spirulina is lower in calcium, niacin, and vitamin B6, but offers more potassium, vitamin E, and copper. The biggest difference between the two supplements may be price. Spirulina is easy to grow and process. Chlorella, on the other hand, has a tough cell wall that must be broken in order to extract its nutrition. As a result, chlorella supplements tend to be more high end.

You can read more about spirulina in our guide Spirulina: The Perfect Food You’re Not Getting.

It’s also worth pointing out that, while neither algae is a great source of vitamin B12, the type found in chlorella is more bioavailable (the body can absorb it more easily). This is good news for those following plant-based diets who often have trouble getting enough B12, which is crucial for controlling mood, mental function, and immune health. According to a 2015 study in the Journal of Medicinal Food, vegans and vegetarians who added a small amount of chlorella to their diets saw a boost in serum markers of B12 concentration.

Chlorella Powder or Tablets?

Chlorella can be taken in three different forms: as a powder, tablet, or even a liquid extract. If you’re interested in using chlorella to supplement your protein intake, a powder will allow you to get the most protein per serving. (By most accounts, chlorella doesn’t taste good on its own, so be prepared to mask it with fruit, other powders, or some kind of mixer.) Tablets, however, make for a convenient vitamin/mineral supplement that you can carry with you without mess or other ingredients.

No matter which chlorella supplement you buy, make sure it says “cracked” or “broken cell wall” on the label. This means that the fiber that guards the algae’s nutrients has been properly crushed so your body can digest the good stuff within.

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