Spirulina: 11 Benefits, How to Take & Side Effects

October 2022

Spirulina is a type of algae that can be used as a food supplement. It is an excellent source of protein, minerals, B-complex vitamins, iron and antioxidants, like phycocyanin and gallic acid. 

Other health benefits that spirulina can offer are preventing cardiac diseases (like heart attach, atherosclerosis and heart failure), complimenting diabetes treatment, helping with allergies and contributing to muscle mass gain. 

Spirulina is a superfood that is sold in its dehydrated form as a pill, capsule or powder. It can be purchased in natural health stores or online. Instructions for dosing and how to take it depend on the ultimate goal to be achieved.

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The main health benefits of spirulina are: 

1. Improve mood 

Because it is a great source of protein, spirulina can provide the body with plenty of energy. This algae has a prebiotic effect, which can strengthen and balance out the good bacteria in the body. This can lead to a greater production of vitamin B6, which has a direct relationship with improved energy levels and mood.

In addition, because it is rich in magnesium, spirulina is able to help synthesize the hormones that promote well-being. 

2. Help with anemia treatment 

Spirulina is an excellent source of iron, which is a mineral that is fundamental for the production of hemoglobin. Hemoglobin, one of the components of red blood cells, can be boosted with spirulina ingestion, making it a great complement to medical treatment of anemia.

3. Decrease bad cholesterol and triglycerides 

Phycocyanin, which is the main antioxidant found in spirulina, inhibits absorption of cholesterol in the intestine, which decreases fat levels in the blood.

It also contains other antioxidants, like betacarotene and gallic acid, which also contribute to the reduction of total cholesterol, "bad" LDL cholesterol and triglycerides in the blood. This can help to reduce the risk of illnesses like heart attacks, atherosclerosis and heart failure. 

4. Treat high blood pressure 

Spirulina can promote the production of nitric oxide, which can help to relax blood vessels and decrease blood pressure. It is important to use spirulina as directed by a doctor to prevent unwanted crashes in blood pressure, which can lead to further complications. 

5. Prevent and treat diabetes

Spirulina contains antioxidants and polysaturated fat, which can decrease blood sugar levels. It can be used as a tool to prevent diabetes and control blood sugar levels. 

Due to its properties, spirulina can also increase insulin sensitivity, which can help to quickly decrease sugar spikes. 

6. Promote muscle mass gains 

In addition to being a source of amino acids, which can contribute to muscle mass gains, spirulina also contains linolenic acid. This is a polysaturated fat that helps to increase resistance levels and strength necessary for muscle-focused workouts.

Spirulina also contains antioxidants that promote post-workout recovery, which is fundamental for muscle gains. 

7. Relieve symptoms of allergic rhinitis

Spirulina has an anti-inflammatory and stimulant effect on the immune system, which can boost antibody functioning. Spirulina can be used a a natural remedy to relieve symptoms of allergic rhinitis, like nasal congestion, sneezing and itching. 

8. Help with weight loss

Spirulina is a source of protein and fiber which can increase digestion time. This can help to keep you full and decrease overeating. 

This plant is low in calories and as great amounts of linolenic acid, which is an antioxidant that is important for metabolism and fat loss. 

9. Prevent early aging

Spirulina is rich in antioxidants, like vitamin A and C, which help to decrease damage caused by free radicals at a cellular level. This can prevent early cellular aging. In addition, due to its antioxidant effects and due to the presence of micronutrients (like zinc and selenium) in its composition, spirulina is also capable of preventing cancer.

10. Reduce inflammation

Because it contains fatty acids like omega-3, spirulina has an antioxidant and anti-inflammatory effect on of the body. Therefore, it can be useful for the treatment of arthritis by reducing joint inflammation and relieving symptoms. 

11. Detox the body

Spirulina is a hepatoprotective agent that can prevent cellular damage in the liver. It can protect the liver from toxins due to its antioxidants effects and can reduce the amount of fat accumulated in the liver. It can also exert an antiviral effect against the herpes simplex virus and hepatitis C.

How to take spirulina

Spirulina is available in powder, pill and capsule form. It can be swallowed or dissolved in water, or added to smoothies, sauces, fruits or salads.

Generally, 1 to 8 g of spirulina is recommended per day, with doses varying with the objectives and health goals. Spirulina should be taken as advised by a doctor or registered dietitian. It can be taken as a single dose or split-up throughout the day.

Possible side effects

Spirulina may cause nausea, vomiting and diarrhea in some people. Although allergic reactions are rare, it is important to monitor for symptoms like redness, itchy skin, or abdominal pain. More severe symptoms, like difficulty breathing, tongue swelling, or difficulty swallowing should be assessed urgently.

Contraindications for use

Spirulina is not recommended for use by children, pregnant women or breastfeeding women due to a lack of scientific evidence ensuring its safety. It should also be avoided by those with phenylketonuria. 

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Written and updated by Daisy Oliveira - Registered Nurse, on October of 2022.


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