Spirulina for Overall Health: Benefits, Side Effects & FAQ
Spirulina is one of the most powerful and protective all-natural superfoods on the planet. Spirulina is a microscopic blue green algae most commonly found in the warm alkaline waters of warm climates.  It may be sourced from Africa, Asia, North America, and South America. 
Most spirulina in the U.S. is grown in laboratories but that doesn’t mean it’s a lower quality source. 
Spirulina is a vegan protein source with a complete amino acid profile found in both dried and freeze dried forms. Spirulina has an amino acid score of 103 (values greater than 100 indicate a complete protein source), has 0mg of cholesterol, 16 grams of protein, and 44% daily value of iron per 28 gram serving.  There aren’t many vegan protein sources that are 57% protein by weight. Spirulina is also exceptionally high in B1, B2, B12, copper, and manganese. 
The main active ingredient in spirulina is phycocyanobilin, which comprises 1% of spirulina by weight.  In the clinical trial setting spirulina can significantly improve exercise performance, decrease cholesterol, blood pressure, blood glucose in healthy and non-healthy individuals, as well as decrease the symptoms of seasonal allergies. This article will discuss spirulina recommended dose, use, benefits, and frequently asked questions.
Spirulina Recommended Dose & Use
The two most popular types of spirulina are spirulina maxima and spirulina platensis.  The recommended dose of spirulina varies based on what issue or condition you’re trying to address. Consume 1 to 8 grams per day if you want lower total and LDL cholesterol; 2 to 7.5 grams per day to improve muscle performance; 2+ grams to control blood glucose, 3.5 to 4.5 grams to lower blood pressure; and 4.5 grams to slow or reverse fatty liver. 
Regardless of which source you pick ensure its high quality, screened for toxic compounds (e.g. microcystins), and heavy metals. Spirulina is commonly cultivated from the open ocean so its quality is largely dependent upon the quality of water in which it’s submerged. To assess tolerance begin with the lowest recommended dose and adjust up or down depending on your body’s response.
A Deeper Look at Spirulina Benefits
Spirulina has numerous positive effects on exercise performance, cholesterol and glucose blood levels, and seasonal allergies.
Spirulina is an all-natural food source with substantial performance-enhancing benefits. When 20 untrained and 20 trained subjects consumed either one gram of spirulina or placebo twice per day for 8 weeks, those consuming spirulina significantly increased their peak force and average force output as well as significantly decreased their perceived fatigue.  These findings show spirulina increases isometric muscle strength and endurance while staving off fatigue.
Sixteen untrained subjects in their early 20s consumed 2.5 grams of spirulina or soy protein before meals three times per day, every day for three weeks and performed all-out treadmill exercise using the Bruce incremental protocol. Those consuming spirulina had significantly lower malondialdehyde (MDA) blood levels, higher blood superoxide dismutase (SOD) and extended time to exhaustion. 
MDA is a commonly used biomarker for muscle damage and oxidative stress whereas SOD is a powerful antioxidant enzyme produced in the human body. Spirulina both fights stressors as well as increases the body resilience to muscle deterioration and fatigue.
A smaller study of nine moderately trained males consumed six grams of spirulina or placebo daily for four weeks and performed a 2-hour run on the treadmill at 70-75% of their VO2max as well as ran at 95% of their VO2max to exhaustion. Those in the spirulina group significantly increased their time to fatigue, decreased carbohydrate oxidation by 10.3%, and increased fat oxidation rate by 10.9% during the 2-hour run. 
Spirulina improves endurance and ensures you burn more fat rather than carbohydrates during moderate intensity exercise. This study also found spirulina significantly increases glutathione levels at-rest and 24-hours post-exercise.  Glutathione is a powerful antioxidant protecting the body from oxidative stress.
Spirulina positively affects the blood profile of both healthy and non-healthy individuals by decreasing cholesterol, blood sugar, and other fats in the blood. 78 healthy subjects between the ages of 60 and 87 consumed either 8 grams of spirulina or placebo daily for 16 weeks. Both males and females experienced a significant lowering of cholesterol levels and increasing of interleukin-2 blood levels. 
Interleukin-2 (IL-2) is a small protein released by cells which increases immune system activity. Only females experienced significantly higher superoxide dismutase (SOD) activity whereas males only experienced decreased Interleukin-6 blood levels. 
Interluekin-6 is a pro-inflammatory protein released by cells. Spirulina not only increases immune system and antioxidant activity but also decreases inflammatory and cholesterol in healthy individuals.
36 healthy subjects consumed 4.5 grams of spirulina daily for six weeks without modifying their dietary habits or lifestyle choices. Although the participants didn’t experience changes in blood glucose or AST (a key liver biomarker), they did experience significantly lower triglycerides, total cholesterol, LDL, systolic, and diastolic blood pressure with high HDL cholesterol blood levels.  Even if you’re healthy spirulina is one of the best all-natural foods to maintain healthy blood levels as you age.
Regarding non-healthy individuals the findings from spirulina supplementation are also favorable. 52 subjects between the ages of 37 and 61 recently diagnosed with elevated cholesterol or fat in the blood (dyslipidemia) consumed 1,000mg of spirulina daily for 12 weeks.
While blood pressure, weight, and body mass index remained relatively static these subjects experienced the following average decreases: triglycerides by 16.3%, low density lipoprotein (LDL) cholesterol by 10.1%, and total cholesterol by 8.9%.  These findings show that spirulina decreases LDL/bad cholesterol without negatively affecting high density lipoprotein (HDL), also known as good cholesterol.
25 patients with Type 2 Diabetes consumed 2,000mg of spirulina daily for two months and experienced significantly lower fasting and post-meal blood glucose levels, decreased total cholesterol, LDL cholesterol, and triglyceride levels. The subjects also experienced a significant decrease in glycated hemoglobin (HbA1c), suggesting improved longer term blood glucose levels. 
A second study on 37 Type 2 diabetic patients dosing spirulina at eight grams per day for 12 weeks found that those with the highest initial triglyceride and cholesterol blood levels experienced the most significant decreases in triglycerides, total and LDL cholesterol, inflammation (IL-6), and blood pressure.  Spirulina not have positive acute on impacts sugar and fat in the blood, but it also appears to be a long-term tool for maintaining blood sugar levels in Type 2 diabetics.
As previously discussed spirulina significantly increased interleukin-2 (IL-2) activity. IL-2 increases the body’s immune system activity and response to stressors. Researchers performed a double-blind placebo control study of spirulina’s effects on subjects with allergic rhinitis, also known as hay fever. Spirulina significantly decreases nasal discharge and congestion, itching, and sneezing compared to placebo treatment. 
The next time you have seasonal allergies, in addition to consuming the over-the-counter or doctor-prescribed allergy medication, consume 1 to 8 grams of spirulina daily and observe your results.
Where can I find Spirulina today?
You can find spirulina as a stand-alone ingredient or as part of a blend in multivitamin and greens supplements in powder, flake, and pill forms. Products that contain spirulina include:
- MTS Machine Greens & Multi – 11 of 14 ingredients in a 4,000mg Green Balance BlendTM per 1 scoop 5.4g serving
- SAN Green Supreme Fusion – 1,000mg per 10.55g 1 scoop serving
- Top Secret Nutrition Super Greens and Reds – 4 of 17 ingredients in a 1,605mg Vitality Greens Blend per 4 capsule serving
- Nutrakey Spirulina – single ingredient with 500mg per 1 capsules
- Nutrex Hawaii Spirulina – single ingredient with 3,000mg per 6 tablet serving
Is spirulina safe and is it stackable with other supplements?
Spirulina is safe to use in moderate doses in both healthy and many non-healthy individuals. Some individuals may experience an allergic reaction to spirulina but it’s not life threatening and occurs infrequently.  If you experience any symptoms of an allergic reaction then discontinue spirulina use immediately and consult your health care professional.
Spirulina is extremely safe to stack with staple supplements like fish oil, whey protein, multivitamins, creatine, BCAAs, caffeine, etc. Do not combine spirulina with immunosuppressant drugs like Adalimumab, Azathioprine, and Etanercept.  Spirulina’s immune boosting properties will fight against the activity of this drug group.
Also avoid taking spirulina if you have an autoimmune disease like multiple sclerosis and rheumatoid arthritis or if you are unable to metabolize the amino acid phenylalanine. 
Spirulina is a complete protein rich in phenylalanine. Spirulina stacks well with most compounds and offers numerous health benefits with no serious side effects. When in doubt consult with your healthcare professional before combining prescription compounds with spirulina.
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