Advertisers call it algae, but it really is pond scum. It is reported to cure health problems that range from anxiety and depression to diabetes, but there is still not enough scientific data to support these claims. Is Spirulina really good for your health?

Biologists used to classify Spirulina as a plant because of its ability of photosynthesis. Nowadays, this organic matter is called “a biomass of cyanobacteria”. As Spirulina has a pronounced blue-green color, it is often used as a color additive in candy and gum.


Spirulina is not a new food: the Aztecs harvested it more than a thousand years ago. However, it was not until recently that Spirulina was proclaimed ‘super-food’ and cure-all for every health problem. The National Institutes of Health (NIH) says that more studies are needed to determine whether Spirulina can be used as a treatment for various health conditions: until there is hard evidence, all health benefits of Spirulina can be explained by the placebo effect.

On the other hand, an ounce (or 28 grams) of dried Spirulina contains almost a third of the recommended daily allowance for protein as well as substantial quantities of vitamins B1, B2, B3 and such minerals as iron, magnesium, copper and manganese. Spirulina contains all essential amino acids; it is moderately rich in vitamin E, potassium and sodium, and low in calories, fats and carbohydrates. Still, there are several reasons why you shouldn’t hurry to trade your steak for a bowl of Spirulina:


  • Many people don’t like the taste and smell of Spirulina (some say that it tastes exactly like pond water), thus it is not a meal you are going to enjoy. For this reason taking dried Spirulina tablets and capsules may be a better option
  • Spirulina is pricey. A gram of Spirulina can be up to thirty times more expensive than a gram of other sources of protein (such as meat and dairy products). Thus, economically speaking, Spirulina is not a viable alternative to good old meat and milk.
  • Bioavailability (i.e. how much of the nutrients are actually absorbed by your body) of Spirulina is still debated, so it might be that your organism simply cannot use all these amino acids and vitamins.
  • Cyanobacteria are known to produce microcystins: toxins that cause various gastrointestinal symptoms. Long exposure to microcystins can lead to liver damage. Although Spirulina itself does not produce toxic compounds, it can be contaminated with other potentially dangerous cyanobacteria.
  • There are also risks of Spirulina being contaminated with heavy-metals and nitrate compounds. The NIH recommends that you thoroughly research the source of Spirulina in the supplements you are going to take.
  • According to the NIH, Spirulina may worsen the symptoms of such health conditions as lupus, multiple sclerosis and rheumatoid arthritis. This organic compound should be avoided by people who have certain autoimmune conditions, and it is still unknown whether Spirulina is safe for pregnant women. Spirulina has several serious side effects: it interferes with drugs that slow blood clotting and weakens the effect of immunosuppressants.
  • Last but not least, a safe dose range of Spirulina is still not established.

By the way, did you know that such vegetables as broccoli and green peas contain lots of protein? They are tasty too!