It’s green. It’s “clean,” and it’s touted as the “world’s healthiest superfood.” Spirulina offers 60% all-vegetarian protein by weight, but can you take too much?

In a word, yes!

People usually begin taking spirulina in order to support their health. A blue-green algae rich in beta carotene, iron, vitamin B-12 and the rare essential fatty acid, GLA, powdered spirulina is a bit of an acquired taste. Even so, converts often swear by its powers to clear the skin, relax the mind, and provide extra energy. Whether added to smoothies and fresh juices or taken in pill form, spirulina initially seems like a winner.

Anecdotal stories suggest healings from malnutrition, cancer, acne, allergies and protein deficiency, to name a few. From an environmental standpoint, spirulina offers ways to stave off deforestation, because it grows in brackish water on non-fertile land. Some manufacturers and proponents consider spirulina a critical supplement for ending world hunger! Indeed, this little blue-green algae does some pretty incredible things.

Unfortunately, very few resources warn of the dangers of ingesting too much spirulina. Though far from a “mainstream problem,” overdosing on spirulina is actually quite common in health nut circles, particularly among the raw foodist crowd, who may use it in salad dressings, smoothies, and fresh juices–all in the same day!

Spirulina contains 3900% more beta carotene than carrots. At first, this sounds like a benefit: more is better, right? Well, not always. The body can convert beta carotene to vitamin A, and in large doses, vitamin A becomes toxic to the liver. High dosage spirulina users often complain of severe body itching, which seems to come from under the skin. No amount of oils, lotions or water seems to alleviate the itch. If you or someone you know has this problem, it could be a sign of severe liver toxicity. Many people experience relief in a few days by stopping spirulina and any other high beta-carotene foods or supplements like goji berries, beets, carrots, E3Live or Crystal Manna and some sea weeds. Once the itching subsides, they can gradually add in lower doses of beta carotene containing foods, but they’ll need to use caution for awhile as their liver recovers.

For people who began taking spirulina for health, the prospect of liver toxicity poses an ironic effect. Spirulina and other superfoods still offer potent benefits, but we need to remember that “super”foods really CAN provide “too much of a good thing.” Recommended doses range from 3-5 grams all the way up to 40 grams per day, which makes it difficult to gage an overdose situation. If you experience unusual symptoms and have been taking a lot of powerful plant foods like spirulina, consider backing those superfoods down a bit. When it comes to supplements and/or superfoods, more does not always mean better.