Spirulina - Muscle Strength And Endurance + Antioxidants
Spirulina is a form of organism (microscopic and filamentous cyanobacteria) that grows in both salty and fresh water. It is a cyanobacterium, also known as blue-green algae, due to its color 1. The name Spirulina is derived from the spiral shape of the algal filaments. Like plants, cyanobacteria can generate energy from sunlight through photosynthesis. There are several species of Spirulina, with the most important ones being Spirulina maxima, Spirulina platensis, and Spirulina fusiformis. Due to their low purine content, cyanobacteria are among the few edible bacteria, as only a small amount of uric acid is produced in the body 2.
Spirulina has been used by the Aztecs 3. Spirulina can even be grown and utilized in space 4. The largest producers are located in the USA, Thailand, India, Taiwan, China, Bangladesh, Pakistan, Burma (Myanmar), Greece, and Chile 5. Spirulina is mainly grown there in large tanks.
Due to its chemical composition, which is characterized by high concentrations of vitamins, minerals, secondary plant compounds, essential fatty acids, amino acids, and pigments, spirulina offers numerous health benefits for human nutrition 6. Spirulina is easily digestible as it does not have cellulose cell walls 7. Fresh algae (85%) can be better utilized than dried ones 8.
However, the health benefits of spirulina ultimately depend on whether the cyanobacterium has grown in clean water - more information can be found under side effects.
In its fresh state, spirulina belongs to the low-calorie foods with 26 kcal per 100 g. This is mainly due to its high water content of 90%. Fresh spirulina contains very little carbohydrates (2.4 g) and fat (0.4 g). The protein content is also lower at 5.9 g. However, when the algae is dried, the nutritional values change significantly. It then contains 290 kcal per 100 g, 23.9 g of carbohydrates, 7.7 g of fat, and 57.5 g of protein. You can find the nutritional values of fresh spirulina and dried spirulina here.
In its dried state (also in powder form), there is a higher proportion of essential fatty acids, which is advantageous. In addition, there is an ideal distribution of omega fatty acids. You can access the nutritional values of spirulina powder here.
Spirulina is also the algae form with the highest content of gamma-linolenic acid (340 to 600 mg per 100 g in powder) 9 10. This fatty acid is converted in the body into anti-inflammatory eicosanoids (prostaglandins and leukotrienes) that play an essential role in immune functions in the body 11. Furthermore, they may contribute to the cell death (apoptosis) of cancer cells 12.
Spirulina contains so-called supramolecular protein aggregates (phycobiliproteins) 13. With 46 to 63 grams of protein per 100 grams of dry weight, spirulina is one of the richest plant-based protein foods of microbial origin 14.
Compared to other algae plants, spirulina exhibits the highest levels of essential amino acids 15. In addition, fresh spirulina, like dulse, has the best amino acid profile among the algae studied. The proportion of essential amino acids in the total protein is approximately 47% 16. Especially the branched-chain amino acids (BCAAs) Valine, Leucine, and Isoleucine, which are particularly valuable for muscle building and maintenance, are present in high amounts in dried spirulina.
Vitamins and Minerals
In addition, spirulina contains higher amounts of vitamin B1, vitamin B2, Niacin, and provitamin A (mainly beta-carotene), which the body can convert into vitamin A. Spirulina in quantities of 2 to 4.5 g is capable of effectively increasing vitamin A levels 20 21. Vitamin A is necessary for vision.
Spirulina powder is rich in Zeaxanthin, with 74 mg per 100 g, which plays an important role in vision as a component of the macula, similar to vitamin A, for eye health 22. Spirulina was able to effectively increase serum levels of zeaxanthin in humans.
Interestingly, in overweight individuals with hypertension, supplementation of 2g of spirulina for three months significantly reduced iron levels, which could potentially be caused by increased levels of heavy metals that hinder iron absorption 23.
Does Spirulina Contain Usable Citamin B12?
Newer studies report vitamin B12 content (38.5±2 and 35.7±2 μg per 100 g dry weight) in spirulina 24 25. Older studies indicate that Spirulina and spirulina tablets primarily contain the biologically inactive pseudovitamin B12 (7-adenyl-cyanocobalamin), which can be absorbed by the body but cannot be utilized 2627 28. Therefore, spirulina and products derived from algae are not suitable for meeting the requirement for vitamin B12 29. We have summarized which vegan foods contain vitamin B12 here.
Improving Muscle Strength and Endurance Performance
Spirulina can help athletes reduce oxidative damage caused during training or competitions. The algae can improve endurance performance and increase muscle strength.
In a study involving trained (at least 3 years of training) and untrained students, supplementation with spirulina increased muscle strength 30. With 2g of spirulina over eight weeks, isometric muscle strength and endurance were increased. Isometric exercises are performed without movement, involving high muscle tension for an extended period. The most well-known exercise is the plank. Overall muscle endurance was minimally affected.
The benefits of spirulina on 16 untrained students who trained on treadmills during the study were examined in another study 31. The participants supplemented their diet with 5% spirulina for three weeks. Preventive effects on muscle damage were observed. The scientists speculate that it could lead to a delay in the onset of fatigue.
The endurance-enhancing benefits of spirulina on moderately trained men were examined in a 2010 study 32. Over a period of four weeks, the participants consumed 6 g per day. During a fitness test, the athletes ran on a treadmill at a moderate intensity (70-75% VO2 Max) for two hours. They then had to sprint to exhaustion at a very high intensity (95% VO2max). The result showed a significant improvement in athletic performance. The time to exhaustion was delayed from 2.05 to 2.7 minutes. Additionally, fat burning (+10.9%) and carbohydrate burning (+10.3%) also increased. Another finding was that the athletes showed lower susceptibility to oxidative damage.
In another study, supplementation with 3 g of spirulina per day resulted in improvements in both physical and mental fitness 33.
Losing Weight with Spirulina
With a 3-month use of spirulina, overweight hypertensive patients were able to significantly reduce their BMI (from 26.9 to 25.0), weight (from 75.5 to 70.5 kg), systolic blood pressure (from 149 to 143 mmHg), and improve their arterial flexibility. 34.
Consumption of spirulina tablets for four weeks resulted in a significant weight reduction of 1.4 kg. 35.
Spirulina is rich in antioxidants that can protect against oxidative damage. Oxidative damage can lead to chronic inflammation, which in turn can result in DNA and cell damage and mutations. Consequences can include cancer, diabetes, cardiovascular, neurological, and pulmonary diseases. 36 37.
Therefore, 8 grams of spirulina per day for 12 weeks showed an effective reduction in lipid peroxidation 38. Additionally, levels of antioxidant enzymes that can protect against fatty acid damage increased.
The most important plant compound that brings antioxidant benefits and anti-inflammatory properties is Phycocyanin. 39 40 41 42 43 44. Phycocyanobilin contained in Phycocyanin is also responsible for the blue-green color. In addition, novel peptide compounds with antioxidant benefits are present as well 45. Phycocyanin accounts for 12.6% of dried spirulina 46.
To preserve the antioxidant potential, spirulina and products derived from it should not be exposed to heat or light 47.
Phycocyanin has the ability to inhibit the growth of specific human leukemia cell lines 48.
Anti-cancer and radical scavenging activities have also been demonstrated in two additional studies. In these studies, spirulina extracts were able to inhibit cancer cell lines in the digestive tract, such as gastric cancer cells 49 50. Additionally, the extracts inhibited cancer cells of the lymphatic system in an early stage of tumor development. According to the scientists, these extracts could potentially be used as a natural alternative to conventional anticancer drugs due to their water-soluble polysaccharides.
Antiproliferative benefits have been observed in various cancer cell lines (breast, liver, stomach) and pancreatic cancer in further studies 51 52. Bioactive peptide and tetrapyrrole compounds significantly reduced tissue proliferation.
Improvement of Blood Sugar and Fat Levels
High cholesterol levels are partly responsible for heart diseases.
A dietary supplement of spirulina tablets (2 g) for two months resulted in a significant reduction in blood sugar levels in non-insulin-dependent diabetes patients 55.
In 25 patients with type 2 diabetes, 2 g of spirulina per day for 2 months, while maintaining a consistent diet, led to a reduction in blood sugar levels 56. Additionally, there was an improvement in lipid levels (HDL cholesterol: +1.4%; triglycerides: -13%).
In another study involving 52 patients with dyslipidemia (abnormal lipid metabolism), the good HDL cholesterol increased and the bad LDL cholesterol decreased. In this study, 1 g of spirulina was used daily for 12 weeks. There was a significant reduction in triglyceride levels by 16.3%, LDL levels by 10.1%, and total cholesterol by 8.9% 57. HDL cholesterol increased by 3.5%. Blood pressure, weight, and body mass index remained nearly unchanged.
Additional studies confirm the lowering benefits on lipid levels 60 61 62 63. With 4.5g of spirulina per day for six weeks, total cholesterol decreased by an average of 16.6% in 36 subjects, LDL cholesterol decreased by 10%, and triglycerides decreased by 24% 64. HDL increased by 15%. In older individuals (60-87 years), cholesterol levels also significantly decreased with 8g of spirulina per day over 16 weeks 65.
Reducing Inflammation Markers
In the same study with older individuals, a significant improvement in inflammation markers was also achieved 66. The anti-inflammatory IL-2 markers increased significantly, while the pro-inflammatory IL-6 cytokines decreased.
Boosting the Immune System
A study has shown that daily consumption of spirulina water extracts (400 ml) leads to an increased production of interferon-γ, which has an immune-stimulating effect 67. This increases the cytotoxic activity of natural killer cells in the body. The body is now better able to recognize and eliminate bacteria, viruses, and abnormal cells such as cancer cells.
Spirulina also contains numerous compounds such as cinnamic acid, naringenin, and kaempferol, which can contribute to skin wound healing 70.
Supporting Oral Health
In tobacco consumers with oral leukoplakia (precancerous condition; causing irritations and sores on the oral mucosa and tongue), complete regression of mouth lesions was achieved in 45% of participants - in the placebo group, it was 7% 71. They used low-dose spirulina (1g over one year). When some participants stopped taking spirulina, 9 out of 20 developed the lesions again in the following year.
One gram of spirulina per day resulted in greater improvement of symptoms compared to Pentoxifylline treatment in subjects with oral submucous fibrosis (mucosal alteration primarily found in India) 72. Pentoxifylline is an anti-inflammatory medication. Another study confirms the benefits in submucous fibrosis 73. In this study, 500 mg of spirulina per day for three months improved symptoms (restricted mouth opening, ulcers/erosions/vesicles).
Alleviating Symptoms of Rhinitis
Spirulina helps alleviate allergic rhinitis (inflammation of the nasal mucosa). Rhinitis can be triggered by environmental allergens such as pollen, pet dander, or even flour dust. In a study involving 127 individuals, the symptoms and physical findings, including nasal discharge, sneezing, nasal congestion, and itching, were significantly reduced with a daily dosage of 2g over a period of six months 74 75.
Similar results were observed with a dosage of 1 to 2g of spirulina over a period of 12 weeks 76. In this study, the release of the inflammatory cytokine IL-4 in response to an antigen was suppressed.
Is Spirulina Beneficial for Anemia?
Anemia is commonly understood as a condition of low blood count. The most common form is iron-deficiency anemia, where the body lacks the necessary iron for blood production.
In a study, the diet of 40 elderly individuals who had previously experienced anemia was supplemented with 3g of spirulina for 12 weeks. This supplementation helped increase the hemoglobin concentrations in red blood cells. However, the number of red blood cells remained unchanged. Significantly, there was an increase in white blood cells (leukocytes), which are important immune cells. Spirulina may alleviate the symptoms of anemia and immunosenescence (age-related immune decline). Further investigations are necessary to explore this matter 77.
Furthermore, spirulina also exhibits detoxifying benefits. A 16-week study revealed that taking 250 mg of spirulina extract twice daily along with 2g of zinc helped individuals eliminate arsenic 78. The participants had previously been exposed to high levels of arsenic through drinking water.
Spirulina is primarily used in dried form as a dietary supplement. For athletes, spirulina powder is particularly suitable as a component for protein shakes due to its high protein content. Since most plant protein sources lack one or two amino acids, spirulina powder can improve protein quality.
In addition, the powder is also suitable as an ingredient for smoothies.
In a 28-year-old man, 3g of spirulina likely led to rhabdomyolysis (breakdown of muscle tissue) 82. The researchers suspect that a spirulina product contaminated with neurotoxin may be responsible.
A 14-year-old boy had an allergic reaction to spirulina 83. He took a normal dosage, and after six hours, symptoms attributed to phycocyanin appeared. In a 17-year-old boy, an allergic reaction (anaphylaxis) also occurred after consuming spirulina tablets 84.
The consumption of spirulina in individuals with autoimmune diseases is the subject of scientific investigations 85. It is advisable to avoid taking it in such cases, as it may exacerbate the autoimmune condition.
Individuals with phenylketonuria should also avoid consuming spirulina 86.
It should be noted that normally, healthy spirulina is capable of absorbing and accumulating heavy metals from contaminated water, which could have harmful effects 87 88 89. Side effects may include headaches, stomachaches, muscle aches, facial flushing, sweating, and difficulty concentrating 90.
In a study, 25 commercial spirulina products were examined for their heavy metal content 91. None of the products exceeded the limits for inorganic elements.
A dosage of one heaped teaspoon per day is considered appropriate, which corresponds to approximately 5 to 10 grams. In most scientific studies, a range of 1 to 10 grams per day is used to achieve the benefits on fat loss and antioxidant activity 92.