Another day, another green powder or so it seems. Spirulina powder – a blue-green algae is one you might see on ingredient lists at your favourite smoothie joint or across your social media feeds – you can find 4.5 million posts tagged #spirulina on Instagram and 19.5 million views with #spirulina on TikTok! But is the nutrition hype legit or is spirulina just a pretty face? Read on to learn about the health benefits of spirulina, plus potential risks and ways to eat the aquatic ingredient that tastes as good as it looks.
What is spirulina?
Spirulina is a type of cyanobacteria, aka blue-green algae, that grows in both fresh water and saltwater in tropical regions (i.e. Central Africa, Asia, Central America), according to a 2020 scientific review. While it can be eaten live or raw (think: taken out of the water, strained, and then eaten), spirulina is most commonly consumed as a powder (the dried, processed form of the algae).
Fun fact: The term “spirulina” actually refers to several cyanobacteria varieties, rather than just one organism or one ingredient. For the purpose of this article, “spirulina” will refer to the species in general. (Similarly, farro actually refers to three types of wheat, but, like spirulina, is often considered a singular food item. Hey, the more you know!)
Spirulina nutrition facts
The World Health Organization has actually dubbed spirulina a “superfood,” according to a 2019 scientific review. Loaded with nutrients such as B vitamins, potassium, and calcium, the aquatic algae also contains phycocyanin, a blue-green pigment that’s responsible for spirulina’s colour and an antioxidant.
In addition to being known for its wide range of micronutrients (it boasts vitamin E, iron, and magnesium, too), spirulina stands out for its “high protein content,” according to the aforementioned review. Now, spirulina is no chicken or Greek yoghurt. But it packs an impressive amount of protein into a small package: 4 grams per tablespoon to be exact, according to the United States Department of Agriculture.
Here’s the nutritional profile of one tablespoon (~7 grams) of dried spirulina powder, according to the USDA:
- 20 calories
- 4 grams protein
- < 1 gram fat
- 2 grams carbohydrate
- < 1 gram fibre
- < 1 gram sugar
Health benefits of spirulina
Okay, so spirulina is packed with benefits and nutrients, but what does that mean for your diet? Read on to learn about the health benefits of spirulina, according to dietitians and scientific research.
Fights Oxidative Stress
Responsible for spirulina’s blue-green colour, phycocyanin is also a potent antioxidant, according to Megan Byrd, R.D., registered dietitian and founder of The Oregon Dietitian. Meaning, it combats oxidative stress by neutralising harmful free radical molecules before they can potentially damage cells and organs and cause oxidative stress.
This is key because high levels of oxidative stress can increase the risk of developing chronic diseases such as cancer and type 2 diabetes. But phycocyanin isn’t playing alone. Spirulina also contains some beta carotene, an antioxidant that gives veggies (hi, carrots) an orange colour, adds Byrd.
Together, phycocyanin and beta-carotene inhibit the activity of free radicals and stimulate antioxidant molecules in cells, making spirulina a stellar antioxidant food, according to a 2016 scientific review.
ICYDK, allergic rhinitis (aka hay fever or, quite simply, allergies) happens when you’re allergic to substances such as pollen, mould, or dust mites, according to the American College of Allergy, Asthma & Immunology. It’s essentially an overreaction of the immune system, which, upon interacting with these allergens, releases histamine, an inflammatory chemical that causes symptoms such as sneezing and itchy eyes.
And while antihistamine medication such as Zyrtec or Claritin can ease these symptoms, spirulina might be able to help, too. In a 2020 study, people with allergic rhinitis took either 2 grams (about 1/4 tablespoon) spirulina or 10 milligrams of cetirizine (the active ingredient in Zyrtec). And the spirulina group experienced more relief – reduced nasal drainage, sneezing, congestion, and itching – than the cetirizine group.
May Support Heart Health
High blood pressure and high blood cholesterol levels are major risk factors for heart disease, according to the Centers for Disease Control and Prevention. The phycocyanin in spirulina, however, may protect your heart by improving these factors. “According to animal studies, phycocyanin may help lower blood pressure by enhancing the production of nitric oxide,” explains Basheerah Enahora, M.S., M.B.A., R.D.N., L.D.N., founder of BE Nutrition. Nitric oxide plays a vital role in vasodilation (the relaxation of blood vessels), which improves blood circulation and, as a result, reduces blood pressure, she explains.
Byrd adds that the algae might also help increase HDL or “good” cholesterol and reduce LDL or “bad” cholesterol, as observed in a 2019 study, but more research is necessary.
May Improve Anaemia
Your body uses iron to make red blood cells, which are in charge of carrying oxygen to all your tissues. But you can develop iron deficiency anaemia – a condition marked by low red blood cells due to low iron intake. The condition can make you super tired, but eating iron-rich foods can help reverse your symptoms. This is where spirulina might come in adding to your health benefits.
Spirulina (a pretty good source of iron) is conventionally used to treat anaemia, according to a 2017 scientific review. While there is limited evidence to support this spirulina benefit, one theory behind it has to do with tiny compounds found in spirulina called polyphosphate bodies, explains Enahora. “Polyphosphate bodies may aid the absorption of iron [in] the intestines, which can improve your iron levels,” she explains.
Could Support Immunity
Adding on to the health benefits, there’s some evidence that spirulina may boost the immune system by enhancing the activity of lymphocytes, aka immune cells that “eat” harmful germs. This effect was observed in a 2020 animal study, in which spirulina increased lymphocyte levels in mice.
A 2016 human study also found that spirulina increases interleukin-2, a molecule that supports a healthy immune response. However, there’s limited human research on spirulina’s effects on the immune system, so more studies involving people are needed to draw any solid conclusions.
Spirulina is “generally recognized as safe” by the Food and Drug Administration, according to a 2017 scientific review. But as with all new-to-you supplements or foods, it’s best to chat with your doctor before giving it a try to ensure spirulina won’t interact with other supplements and/or prescription drugs already in your regimen. This is especially important if you’re taking immunosuppressants, which may negatively interact with spirulina, according to Icahn School of Medicine at Mount Sinai.
In some folks, spirulina can cause side effects such as digestive issues, muscle pain, sweating, facial flushing, and headaches. And while spirulina might have the power to improve allergy symptoms, it can potentially cause allergic reactions, too.
In a 2020 case report, two people developed hives, itching, and difficulty breathing after eating spirulina. If you have a history of allergies, speak to your doc before adding the algae to your routine. The same goes if you’re pregnant or breastfeeding, as there’s minimal evidence on how spirulina affects either.
What’s more, spirulina poses the risk of being contaminated with heavy metals such as nickel, aluminium, or lead, according to a 2018 article. These metals can cause health issues such as nervous system damage and kidney problems, according to a study in the Science of the Total Environment.
Basically, spirulina can absorb heavy metals from the environment so effectively that it’s been purposely used to remove metals from wastewater in industrial scenarios. Play it safe by buying spirulina from a reputable brand.
How to buy and eat spirulina
Looking for the healthiest option? Reach for spirulina powder, which typically contains just one ingredient: spirulina. This means it offers a purer, more potent nutrient profile compared to other supplements, says Kelsey Lorencz, R.D., registered dietitian and founder of Graciously Nourished.
But heads up: Spirulina powder has a fishy pond-like taste and smell that some people might notice. If you’re not a fan, “a gummy, pill, or a mixed powder [blend] might be a better option, but you’ll want to watch out for added sugars, flavours, and dyes” notes Lorencz. Enahora recommends combining straight spirulina powder with citrus to reduce the intense fishy profile.
Also, when choosing any kind of spirulina supplement, be mindful of its source. “Look for spirulina harvested from natural lakes or grown in controlled commercial ponds,” says Enahora, as this will limit the risk of heavy metal contamination mentioned above.
While you’re at it, make sure the brand has third-party certifications, adds Enahora. Third-party certification means that an independent organization has tested the product for safety and quality. This is especially important since “spirulina production, dehydration, and storage can significantly reduce its antioxidant content,” notes Enahora, but buying a third-party certified product will ensure you get the most bang for your buck. Usually, you can these certs on a product’s packaging.
Spirulina is also available live (i.e., not dried) from speciality manufacturers, such as Raw Living Spirulina Fresh Raw Living Spirulina (Buy It, $75, rawlivingspirulina.com). This version is typically used in smoothies and drinks. Brands that make raw, live spirulina claim that it’s more nutritious because it’s not processed as is the case with a powder, but “it’s tough to find research comparing the two,” notes Lorencz.
Plus, live spirulina is more expensive and requires refrigeration, as it’s less shelf-stable than powder. TL;DR – spirulina powder is the more practical and budget-friendly option.
If you’re ready to give spirulina a spin, here are a few tasty ways to use it at home:
How to enjoy spirulina
In a smoothie. One of the easiest ways to enjoy spirulina is to add 1 to 2 teaspoons to your morning smoothie, such as this orange and vanilla hemp protein shake. The orange will tone done the fishy smell, but you can also try blending it with other citrus fruits, like lemon or grapefruit.
In juice. Byrd recommends stirring spirulina powder into juice. Again, 1 to 2 teaspoons will do the trick, and citrus juices (i.e. orange juice) are your best choice.
In energy balls. Give your energy balls a nutritional boost with spirulina, suggests Enahora. Add one teaspoon to your go-to energy ball recipe or try these chocolate spirulina superfood energy bites by food blog Grateful Grazer. If you’re concerned about the fishy taste, try adding lemon zest to the recipe.
In banana ice cream. The next time you make banana ice cream, add 1/2 to 1 teaspoon of spirulina powder. Better yet, add a few wedges of oranges. The spirulina will add nutrients and colour, says Enahora, while the orange will tame its fishy notes.
In soup. Spirulina also works well in green soups, where it deepens the dish’s colour. Try it in this vegan green soup with spirulina and coconut oil.
In overnight oats. Thanks to spirulina, you can switch up your breakfast game and make blue-green oats. Need inspo? Check out this green goddess overnight oats recipe by Hey Nutrition Lady.
This story first appeared on www.shape.com.
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