What is spirulina?
Spirulina (Arthrospira platensis) is a unicellular blue green algae which thrives in salt water and brackish water bodies. It grows well in alkaline environments which have a pH of 10-12.
It is a microscopic filamentous cyanobacterium whose name is derived from its spiral or helical nature of the filaments.
It grows well in countries like Greece, India, Japan, United States and Spain etc. which have a sunny climate. Spirulina requires alkaline lakes with high pH for growth.
Spirulina has been used as a food supplement for several civilisations from the beginning of the Aztec civilisation. A few countries such as Africa, have been using spirulina as a nutritional supplement from the time of famine, where the native populations consumed only spirulina as food for more than a month.
Phycocyanin and spirulina
Phycocyanin is a water soluble pigment which gives spirulina its bluish tint. It is a powerful water soluble antioxidant with free radical scavenging properties. It can also prevent lipid peroxidation.
Nutritional composition of spirulina
- 60% of spirulina is a protein of high biological value (contains all the essential amino acids). It is also easily digestible.
- It has higher beta carotene in comparison to other foods.
- It is whole food source of gamma linolenic acid.
- It is rich in B vitamins, minerals, chlorophyll, enzymes, carotenoids, sulpholipids, glycolipids, phycocyanin, superoxide dismutase, RNA and DNA.
- It helps complement the diet with essential phytonutrients which are lacking in the daily diet.
Spirulina contains:
- >180% calcium than milk
- >670% protein than tofu
- >3100% beta-carotene than carrots
- >5100% iron than green leafy vegetables
- > antioxidants in 3g of spirulina than 5 servings of vegetables and fruits.
Nutrient value table of Spirulina pacifica
| Nutrients | Nutrient value/100g Spirulina pacifica |
| Total calories (Kcal) | 333 |
| Calories from fat (Kcal) | 50 |
| Fat (g) | 5 |
| Saturated fat (g) | 2.2 |
| Cholesterol (mg) | 0 |
| Total carbohydrates (g) | 16 |
| Dietary fibre (g) | 7 |
| Sugars (g) | 0 |
| Protein (g) | 67 |
| Vitamin A (beta carotene) (IU) | 375000 |
| Calcium (mg) | 333 |
| Iron (mg) | 217 |
| GLA (mg) | 1067 |
| Superoxide dismutase | 36000 |
Medicinal usage of spirulina
- Helps with chronic fatigue – Spirulina can promote better energy levels due to polysaccharides (Rhamnose and glycogen) and GLA which is easily absorbed in human cells. It also helps increase the gut bacteria – Lactobacillus which produces vitamin B6 involved in energy production.
- Anti-inflammatory – Spirulina has the ability to inhibit the release of histamine. It helps reduce nasal discharge, sneezing, itching, and congestion. It also helps in treating allergic rhinitis. Nutritional deficiencies may impact the inflammatory response. Spirulina can compensate for these nutritional deficiencies and promote its anti-inflammatory effect.
- Lowers cholesterol and improves heart health – Spirulina can help lower cholesterol, LDL and triglyceride levels and increase HDL levels. However, this benefit of spirulina is understudied and requires more research to confirm its efficacy.
- Potent antioxidant – C-Phycocyanin found in spirulina has antioxidant and free radical scavenging properties.
- Immune boosting – Nutritional deficiencies may impact the immune response (due to changes in T-cell production, IgA antibody response, cytokine activity and NK-cell activity). Spirulina can compensate for these nutritional deficiencies and boost immunity.
- Anti-cancer effect – Many animal studies conducted suggest that spirulina may help in cancer prevention due to its antioxidant and immunomodulatory properties. An animal study reported that 45% of the study cohort had regression in leukoplakia after 1 year of supplementation of cancer.
- Antiviral effect – S.platensis contains Calcium spirulan (Ca-Sp) which prevents replication of many enveloped viruses such as Herpes simplex type I, measles and mumps virus, influenza A virus and human immunodeficiency virus-1 virus (HIV-1).
- Skin and hair health – Spirulina can improve skin tone and elasticity by providing essential nutrients to the skin. The antioxidants present may prevent oxidation in the epidermis and dermis layers of the skin. Other nutrients such as GLA, vitamin B, vitamin E, carotenoids etc. can play an important role in the prevention of skin cancer, hair thinning and baldness.
- Brain health – Spirulina contains folate and B12 which help in cognitive protection. It may also be used as a supplement in patients with depression to improve symptoms.
Dosage and uses of spirulina
- Safe recommended dose of spirulina is 3–10 g/day for adults.
- Spirulina is available in different forms such as tablets, powders etc.
- It is not to be consumed during pregnancy and lactation.
- Spirulina must only be taken with warm or cold water. Drinking extra water to flush down spirulina can help in better absorption of nutrients.
- It is suggested to avoid juices, tea, soda, milk etc. for a minimum of 30 minutes after consumption for better absorption.
Contaminants and health risks
Spirulina does not come without its individual risks. Studies conducted suggest that spirulina contamination and health risks are serious and are due to lack of safety regulations.
- Cyanotoxins – Cyanobacteria may produce toxins such as microcystins, nodularin, saxitoxins, anatoxin, etc. A study revealed that a sample which was assessed had a concentration of 11mcg of Anatoxin A/g. Toxins such as anatoxin and saxitoxin can manifest as neurotoxicity symptoms while microcystin can get accumulated in the liver and lead to liver cancer.
- Heavy metals – Even though lead absorption by spirulina may be beneficial in the removal of iron from contaminated water, it can be harmful for health. Similarly higher than safe consumption of mercury, cadmium, lead, arsenic etc. can prove to be fatal.
- Pesticides – Biocides such as pesticides, herbicides, insecticides, fungicides etc. may be detected in spirulina products. This may be due to the lack of established regulatory limits for biocides.
- Polycyclic aromatic hydrocarbons (PAH) – PAH may accumulate in spirulina products due to environment related accumulation and incorrect thermal processing.
Though Spirulina has potent beneficial effects, it is still under review for its various health benefits. It is recommended to always speak to a health care provider to understand dosage, suitability and instructions of use.
Mayuri,
Dietetic Researcher, Simplyweight
