Blue-Green Algae

Nutritional Compound



Blue-green algae, better known as spirulina, is one of the most primitive of algae species. In the last ten years, it’s been used primarily as a food source because it appears to be a rich source of protein and numerous vitamins and minerals. It’s surrounded by controversy because there are those who say algae is a powerful performance enhancer, yet the science has been slow to lend its support. We’ll keep our eyes on this one, but we’re not setting up any algae tanks in our offices as of yet.

Other names for Blue-Green Algae

spirulina, Aphanizomenon flos-aquae (AFA)

Where to find Blue-Green Algae

Spirulina is a species of blue-green algae in the Cyanobacteria family. Most commonly, Spirulina maxima and Spirulina platensis are used commercially. This algae forms naturally on lakes in Central and South America and in Africa, but for commercial purposes, it’s cultivated from tanks in Asia, Hawaii, and California. Aphanizomenon flos-aquae (also called AFA or “Super Blue-Green Algae”) is cultivated from Klamath Lake in Oregon.


Why athletes use Blue-Green Algae

In an effort to increase energy, improve performance, enhance protein building and muscle recovery, some athletes have tried blue-green algae. However, it appears that the supplement is most useful for individuals who need greater levels of nutrients, like vitamins and minerals, in case of deficiencies, not those looking for performance benefits like a quick pick-me-up for a workout or race.

Ways that Blue-Green Algae can enhance Fat Loss:
  • Originally theorized that it may help stabilize blood sugar levels and therefore promote weight loss
Ways that Blue-Green Algae can enhance Energy & Endurance:
  • Potentially cause a “lift” by providing a direct source of glycogen


Signs of Blue-Green Algae deficiency

No deficiency conditions are known to exist.

Potential uses for Blue-Green Algae

Research indicates that Blue-Green Algae may be useful in the treatment of:

  • Attention deficit disorder (ADD)
  • Alcoholism
  • Cancer Prevention (particularly oral)
  • Hemorrhoids
  • Herpes
  • High cholesterol levels
  • Liver protection
  • Impaired immune function
  • Obesity


More about Blue-Green Algae

Blue-green algae is, quite simply, just that — an algae. More commonly known as spirulina, it’s a single-celled microorganism that’s been around for something like forever. (Blue-green algae is one of the most primitive of algae species.) It grows naturally in salty lake water and looks a lot like pond scum. And in the last ten years or so, it’s been grown, dried, and marketed as a nutritional supplement.

What’s interesting about this primordial pond scum is that some scientists suggest it may produce up to 20 times more protein than soybeans grown in the same amount of “land.” (Of course, algae’s grown in water.) Some research also indicates spirulina contains the highest concentration of protein (60%), amino acids, beta-carotene, gamma-lineolenic acid, and trace minerals of any plant. It also provides calcium, potassium, manganese, copper, and zinc.

Still, this algae doesn’t appear to be the wonder nutrient proponents proclaim. And, there is a great deal of controversy surrounding it.

Past and present uses

Evidence suggests Mexico’s Aztecs and Central Africa’s Kanembus looked to spirulina as a food source: the algae may have helped combat poor nutrition. Today, native Africans, Asians, and South Americans cultivate blue-green algae for consumption. The World Heath Organization, WHO, has even fed spirulina to malnourished children in underdeveloped countries because it appears to reduce incidence of a type of blindness caused by Vitamin A deficiency.

Energy or performance enhancer?

Blue-green algae is available as a dietary supplement in health-food markets worldwide, touted by manufacturers as an energy and performance enhancer. This may be true if you’re nutritionally deficient. With its list of nutrients, blue-green algae can be thought of as a multivitamin. But the average healthy American isn’t as likely to see energy benefits as, say, a child from a Third-World country.

But before we dismiss this supplement completely, we must consider that some evidence does support its use for energy enhancement. In fact, blue-green algae is fed to race horses because it contains a storage form of glucose called glycogen that’s broken down in a unique manner in the liver to give a rush of energy similar to adrenaline. Most proteins and carbohydrates are not quick energy foods because they have to be converted to glycogen and can be difficult to digest.

In truth

While blue-green algae does appear to be proportionately high in many nutrients, it should be noted that very large quantities are needed to get significant amounts of these nutrients. And some contend that it tastes a lot like fresh-cut grass and may not be appetizing to the average person. And if you can’t “choke down” large quantities, you won’t get enough of the nutrients it contains to make any difference.

Claims of greater fat loss

Researchers originally theorized blue-green algae may help stabilize blood sugar levels and promote weight loss. One small preliminary study even indicated that overweight people who supplemented with spirulina lost significantly more weight than those taking a placebo. Recent research has quieted that claim: another small study showed that the algae was, in fact, no more effective than a placebo.

Therapeutic uses

The protein, iron, carotenes, and vitamins concentrated in blue-green algae make it a prime source of natural vitamins and minerals. Its direct therapeutic effects, however, require further research for substantiation.

In the fight against high cholesterol, blue-green algae was shown in preliminary studies at Harvard Medical School to significantly reduce blood cholesterol levels in laboratory animals compared to those fed a diet of soybean oil. The researchers pointed to algae’s polyunsaturated fatty acids (PUFA’s), which are also found in soybean oil, and alpha-linolenic acid, which is not. One small study with humans supported a possible role against high cholesterol levels; however, follow-up, double-blind, placebo-controlled studies are indicated.

Research in India indicates that blue-green algae may significantly reduce incidence of oral cancer. Yet further studies are needed to verify claims that blue-green algae is an effective anticancer agent.

Studies indicating that algae benefits children with attention deficit disorders (ADD and ADHD) have not been corroborated with scientific study, although doctoral research at the University of Central America in Nicaragua found an 81% improvement in academic scores when children took one gram of AFA every day for 6 months, and researchers in the U.S. report significant improvement in ADD symptoms when children take AFA supplements.

In conclusion

In an effort to increase energy, improve performance, enhance protein intake and muscle recovery, some athletes have tried blue-green algae. However, it appears that the supplement is most useful in individuals who need greater levels of nutrients, like vitamins and minerals, not those looking for enhanced performance or a quick pick-me-up. Perhaps future research will provide evidence to the contrary…? At any rate, we’ll likely continue hearing controversy surrounding this algae. Only time and research will tell the real story on whether this is a wonder nutrient, pond scum, or most likely, something in between.



Three to five grams of dried herb taken three times daily is typically reported, but doses ranging from one to eight grams per day have been noted.


Take blue-green algae with meals.


Currently, the maximum safe dose is 50 grams daily.

Synergists of Blue-Green Algae

No synergists have been noted.

Safety of Blue-Green Algae

Canada’s Health Canada has issued a warning that because blue-green algaes produce cyanotoxins, including liver-damaging mycrocystins, as byproducts of metabolism, people should not consume blue-green algae obtained from natural lakes for any prolonged duration.

Blue-green algae is not recommended for children.

Blue-green algae may absorb any heavy metals, such as mercury and lead, present in water where it forms. Heavy metal toxicity is a serious concern; however, one study indicates that to achieve dangerously high mercury and lead levels, it would be necessary to ingest more than 77 grams of blue-green algae per day.

Toxicity of Blue-Green Algae

Daily doses exceeding 50 grams may result in the ingestion of excessive amounts of protein, which, when metabolized, form uric acid, a substance that can trigger gout and/or kidney stones. Individuals with gout or who have already experienced kidney stones are at increased risk.

Bans and restrictions

None reported.


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