Spirulina is cyanobacterium (blue-green algae) that grows in alkaline water. Spirulina is rich in protein and nutrients and been used as a food source in Africa for centuries. Today, spirulina powders and capsules are popular nutritional supplements. And, the rich antioxidant properties and therapeutic benefits are not just for people. Preliminary research in Australia has shown that livestock feed that’s been enhanced with nutritious spirulina to improve growth, fertility, aesthetic and nutritional quality in farm animals. 
Spirulina and Eye Health
Spirulina is a rich dietary source of zeaxanthin, a xanthophyll. Xanthophyll are substances similar to carotenes, the pro-eye compounds found in carrots. Zeaxanthin is a xanthophyll that has nutritional importance to human eyes in that sufficient intake may reduce risk of cataracts and age-related macular degeneration. Observational studies have shown a connection between adequate zeaxanthin and lower incidence of age-related macular degeneration. 
Spirulina and Liver Health
Incidence of non-alcoholic fatty liver disease is on the rise. It is often a side effect of obesity and poor diet that occurs when a fat overload in the liver is coupled with oxidative stress. The best strategy against it is to lose any excessive body weight (fat) and make the appropriate dietary changes that will help decrease lipid levels. Additionally, supplementing with spirulina may support a boost in fatty acid oxidation.  Many, many animal models have shown spirulina to promote liver health by lessening redness through anti-oxidative mechanisms.  
A Chinese study involving mice showed that supplementation of spirulina and vitamin C could reduce enzyme activity known to be damaging to the liver. No surprise, the effect was credited to the antioxidant levels. 
Spirulina and Brain Health
You may have heard of the “blood-brain barrier”, it is a separation of the brain and spinal cord from the other organs in the body. This natural mechanism is in place to keep infections from reaching your most vulnerable tissues. Your brain contains microglia cells that are the immune system for your nervous system. It’s the job of these microglia cells to constantly scavenge your central nervous system for plaque, damaged neurons, and harmful agents. When harmful agents do manage to cross the blood-brain barrier, microglial cells spring into action for defense. However, activated microglia produce redness and in the brain, which is thought to be a major component in the development of degenerative brain diseases. Spirulina may be beneficial and provide resistance to the oxidative aspect of microglial cell activation.  Research by the Department of Otolaryngology at Buddhist Dalin Tzu-Chi General Hospital in Taiwan found similar oxidation-reduction properties in Spirulina and even stated that these properties may fight against memory loss. 
The Dietary Supplements Information Expert Committee of the United States Pharmacopeial Convention undertook a safety evaluation of spirulina and assigned a Class A safety rating.  Spirulina is generally considered safe and is backed by a long history of use as a food source and safety in animal models. However, when purchasing spirulina or any produce you’re going to put into your body, it is important to ONLY invest in quality products that are responsibly produced so as to avoid contamination and guarantee safety. 
- Dr. Edward F. Group III, DC, ND, DACBN, DCBCN, DABFM
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