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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