It has been consumed by the Aztecs and astronauts in space, but spirulina is also a popular dietary supplement for everyone else. This fresh- and salt-water algae is a rich source of vitamins, proteins, and nutrients — plus, it has anti-inflammatory properties and mixes well into smoothies. But not all brands offer a high-quality supplement. In short, the best spirulina powders pay close attention to their sourcing and manufacturing processes.
As with all nutritional supplements, you need to watch for additives; cheaper alternatives will often throw in unwanted ingredients (fillers like soy, gluten, preservatives, and artificial flavors and colors) to lower the overall production cost. Unfortunately, this also lowers the quality — especially for those with allergies or sensitivities.
When it comes to once-living organisms like spirulina, however, consumers also need to look out for toxins that came before the production process. Since it's an algae-based supplement, the cyanobacteria may have been exposed to heavy metals and other contaminants while in the water. As a result, it can be worth the extra cost for products that have been lab tested to ensure quality.
Just note that like with all supplements, spirulina can cause side effects for some people, ranging from mild to more serious, so you should talk to your doctor first before trying it. It may also slow blood-clotting and worsen certain autoimmune diseases.
With all this in mind, here are the three best spirulina powders on Amazon.
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1. The fan favorite
- Price per ounce: $2.37
- Free of: animal products, gluten, soy, fillers, preservatives, and dyes
With more than 9,000 reviews and an overall rating of 4.6 stars, Pure Hawaiian's spirulina powder is a clear favorite on Amazon. Yes, it's more expensive than many of its competitors, but the brand claims that it's "better than organic" because it's grown in Kona, Hawaii, in a GMP-certified underwater facility. The company also lab tests every batch to ensure quality, and they offer the product in a wide range of different forms including tablets and powders. Many reviewers also noted that it tastes pretty good.
One reviewer says: "Best Spirulina I have tried. Have been through a few brands and this is the best tasting. Other things I like are that it comes in a glass container and a large 16oz size that is available through subscribe and save. Also it is grown on ocean water that is pumped up from 2000' below the surface, I like that better than using a man made nutrition base."
2. The budget one
- Price per ounce: $1.64
- Free of: animal products, soy, preservatives, gluten, GMOs, artificial colors, or artificial flavors
If you're not yet sure how spirulina might affect you and you want to give it a try before investing in a huge batch, opt for this bag from BN Labs. Each 7.93-ounce order costs less than $15, but the company still adheres to strict quality processes to ensure a great product. The brand is USDA-certified, third-party tested, and uses a five-step quality process that involves growing the algae in organic farms that utilize underground, alkaline spring water. That explains the 4.6-star rating and more than 2,000 Amazon reviews.
One reviewer says: "I like that it is in powder form and a great price point for quantity of product. Taste is distinct but not overpowering. I am 70% done with first bag and have already purchased a second bag."
3. The best value
- Price per ounce: $1.25
- Free of: animal products, soy, yeast, gluten, GMOs, preservatives, artificial colors, and artificial flavors
Finally, for those looking for the lowest price per serving (without compromising on quality), there's Micro Ingredients' organic spirulina powder. For $22, you get a 1-pound bag, which breaks down to a little more than $1 per ounce. This brand is USDA-certified organic, vegan, and non-GMO, and while they don't outwardly note that it has been lab tested to ensure quality, reviewers on Amazon have vouched for it, giving it an overall rating of 4.6 stars after more than 3,000 ratings.
One reviewer says: "This organic spirulina is great!! For the price and value it is exceptional. I will continue to purchase this product and will recommend to all my family members and friends who also use only organic spirulina. Thank you."
Al-Dhabi N. A. (2013). Heavy metal analysis in commercial Spirulina products for human consumption. Saudi journal of biological sciences, https://doi.org/10.1016/j.sjbs.2013.04.006
Karkos, P. D., Leong, S. C., Karkos, C. D., Sivaji, N., & Assimakopoulos, D. A. (2011). Spirulina in clinical practice: evidence-based human applications. Evidence-based complementary and alternative medicine, https://doi.org/10.1093/ecam/nen058