Spirulina Nutrition Facts | Complete Nutrient Guide

Spirulina is one of the richest food sources known to man. This blue-green algae — technically a cyanobacterium now formally classified as Limnospira platensis — is 65 percent protein by composition and contains B vitamins, beta-carotene, gamma linoleic acid (GLA), iron, calcium, magnesium, manganese, potassium, zinc, and bioflavonoids. It is considered a complete protein since it contains all the essential amino acids.

Understanding Spirulina nutrition facts begins with appreciating its extraordinary nutrient density. Dried Spirulina is approximately 57% protein, 24% carbohydrates, 8% fat, and 5% water. In a reference amount of 100 g, dried Spirulina powder supplies 290 kilocalories and is a rich source of numerous essential nutrients, particularly B vitamins (thiamin, riboflavin, and niacin) and dietary minerals such as iron and manganese.

Spirulina provides the most remarkable concentration of nutrients known in any food, plant, grain, or herb. It offers a great whole-food alternative to isolated vitamins and minerals, containing vegetable protein, beta-carotene, iron, trace minerals, and GLA alongside all essential amino acids.

Spirulina has been a valuable food source for Mexicans, Asians, and Africans for thousands of years. In Mexico circa 1300 AD, the Aztecs harvested Arthrospira from Lake Texcoco and used it to make a dry cake called tecuitlatl. They skimmed Spirulina from lakes in the Valley of Mexico with nets or shovels, sun-dried it, and cut it into bricks that would remain edible for a year. The Aztecs ate it with tortillas or toasted corn, and sometimes combined it with chiles and tomatoes to make a sauce.

In Africa, the use of Spirulina as food in Chad likely dates back to the ninth century AD during the Kanem Empire. The Kanembu people harvest Spirulina from Lake Chad and process it by hand into cakes known locally as "dihe" for use in sauces for meat and fish. This tradition continues today and remains an important part of the local economy.

Modern scientific interest in Spirulina began in the 1970s when researchers at the French Petroleum Institute studied the algae's high protein content, drawing the attention of the scientific world and marking the beginning of large-scale production. The World Health Organization has used it to feed malnourished children in India, underscoring the significance of Spirulina nutrition facts for global health.

Protein and Amino Acids

The most abundant component of Spirulina is protein, which accounts for 50–70% of its dry weight. Spirulina is rich in essential amino acids including phenylalanine, leucine, valine, tryptophan, threonine, lysine, isoleucine, and methionine. The amino acid profile also shows high levels of alanine, glycine, and glutamic acid. Because Spirulina contains all essential amino acids, it is classified as a complete protein.

Beneficial Fatty Acids

The lipid content of Spirulina is about 8% by weight. Among its polyunsaturated fatty acids, gamma-linolenic acid (GLA) stands out as an essential fatty acid the body uses to produce anti-inflammatory agents. Linoleic acid is also present. Certain constituents such as polysaccharides and GLA are absorbed easily by human cells and may help support energy release.

Phycocyanin: The Signature Bioactive

Among the abundant bioactive compounds in Spirulina, phycocyanin stands out as a characteristic pigment-protein complex. C-phycocyanin (C-PC) is one of the major biliproteins of Spirulina with antioxidant and radical scavenging properties. It is a selective cyclooxygenase-2 (COX-2) inhibitor, which contributes to Spirulina's anti-inflammatory activity.

Additional Bioactive Compounds

Spirulina also contains glycolipids, sulfolipids, phycobilins, flavonoids, and the sulfated polysaccharide calcium spirulan (Ca-Sp). Beta-carotene and other carotenoids contribute to its antioxidant capacity. It is worth noting that Spirulina contains predominantly pseudovitamin B12 rather than active vitamin B12, so it should not be relied upon as a sole source of this nutrient.

Given its extraordinary nutrient density and the breadth of Spirulina nutrition facts, this whole-food supplement may appeal to a wide range of individuals. Those seeking comprehensive nutritional support from a single plant-based source may find Spirulina particularly valuable as a whole-food alternative to isolated vitamins and minerals.

Research suggests Spirulina may be especially relevant for individuals looking to support healthy iron levels and hemoglobin production, as clinical studies demonstrate improved hematological parameters in multiple populations. Older adults concerned with healthy aging may also benefit, as RCTs show Spirulina supplementation may reduce oxidative stress markers and support immune function in elderly populations.

Athletes and active individuals may appreciate Spirulina's ergogenic potential. A systematic review of 13 controlled trials found it may increase oxygen uptake and improve exercise tolerance during submaximal exercise, while also supporting recovery by reducing exercise-induced oxidative stress and fatigue.

Individuals interested in cardiovascular wellness may find the lipid-related research compelling — meta-analyses encompassing over 1,000 participants suggest Spirulina supplementation may promote healthy cholesterol and triglyceride levels. This product is dairy free, soy free, and grain free, making it suitable for individuals with certain dietary restrictions.

Spirulina should be used with caution by people with autoimmune conditions, those who are at risk of hypoglycemia or hypotension, those at risk of bleeding, or those with impaired liver function. People who have phenylketonuria should avoid Spirulina, as it contains the essential amino acid phenylalanine (2.6–4.1 g/100 g).

Take one (1) tablet, six (6) times daily with meals. Store in a cool, dry place and away from direct light.

Each tablet provides 500 mg of Spirulina. This product contains 100 tablets per bottle.

Research studies have used Spirulina in doses ranging from 1 g to 19 g per day. Higher doses in the range of 4 to 10 grams daily appear in studies examining lipid profiles and endurance exercise support, while a lower dose of 2 grams daily was used in allergic rhinitis research. A safe upper limit of 10 grams per day is commonly cited in the literature. The most commonly reported side effects at higher doses include gastrointestinal upset, fatigue, dizziness, headache, and skin irritation.