Spirulina is a type of blue-green algae which has been promoted for many years as a health food supplement. In the last twenty years there has been much discussion about certain Spirulina side effects and what causes them. There has also been much avoidance of the issue by certain producers of Spirulina, and equally as much exaggeration of the issue from the other side. A lot of this has arisen from a confusion about what is actually meant by Spirulina, what different types are available and how they are prepared. The truth is that certain products sold as Spirulina are quite often made from other blue-green algae instead, which, when improperly prepared can contain very dangerous levels of toxins which attack the liver. There is also very little regulation in its production. So how does the consumer know which types are safe and which or not? Or should people just avoid it altogether?
The issue surrounding the potential seriousness of Spirulina side effects first arose in 1999 with a warning by the Canadian Health Protection Branch that Spirulina products could contain potentially dangerous levels of toxins known as microcystins. These toxins can cause serious liver damage in large doses. They found that products which were made from certain blue-green algae which was harvested from the wild contained levels of microcystins which were above the recommended maximum daily intake of the World Health Organisation. These products are often sold as Spirulina. The report stated that: “Adverse symptoms from long-term use of these products (weeks to months) may not be obvious but could range from a feeling of general malaise or gastrointestinal discomfort, to jaundice.” They did however state that “Based on the results, products made only from Spirulina blue-green algae are no longer considered a microcystin-related health risk.” In other words, reported Spirulina side effects, are in fact not caused by Spirulina at all, but by other species of blue-green algae. So how exactly do we tell what’s safe and what’s not?
The problem is that there is a lot of confusion about what can actually be called Spirulina, and various other blue-green algae are being falsely sold as Spirulina. The main species of blue-green algae that goes into good quality nutritional Spirulina is known as Spirulina platensis. In actual fact, scientists have decided that the species belongs in a different genus, so it is now officially known as Arthrospira platensis. However, in common usage it is still known as Spirulina, and this is what consumers should be looking for in Spirulina supplements if they are to avoid all of the supposed Spirulina side effects.
In May 2000, the Oregon Department of Health further helped in nailing down the culprit. They stated in their report that many blue-green algae products on the market contained a species called Aphanizomenon flos-aquae. This is not a species of Spirulina and it is generally harvested from the wild, often in Upper Klamath Lake in southern Oregon. The problem with this is that another species of blue-green algae is common in that lake known as Microcystis aeruginosa. This is one of the species that produces microcystin toxins and it is often inadvertently harvested alongside Aphanizomenon flos-aquae. These microcystins then end up in products being sold as Spirulina and are what is to blame for the reported side effects.
From these two reports it is clear that taking the wrong blue-green algae products can result in potentially serious consequences. But the truth is that the Spirulina side effects that have been reported are actually caused by other species of blue-green algae which are sold as Spirulina. True Spirulina is a product filled with nutrients and has been hailed by the World Health Organisation as having great potential for battling global malnutrition. It has also been suggested by NASA that it could be an excellent food for growing in long distance space travel. There are companies that are very heavily regulated and selling very good quality pure Spirulina platensis grown in controlled conditions. There is also a strain known as Spirulina pacifica or Hawaiian Spirulina which has been developed by scientists from Spirulina platensis and is also very heavily regulated in its production. These are the companies that people should be going to if they wish to get the benefits of blue-green algae without the potentially dangerous side effects.