Spirulina Benefits: What Is The Blue-green Algae Used For? (Overview, Dosage, and Side Effects)

Spirulina is a nutrient-dense superfood that can improve your health in many different ways.

When it comes to superfoods, spirulina is often top of the list. It has more to offer than many of the everyday foods we associate with being healthy.

It is hard to find one supplement that can influence so many different aspects of a person’s health. But this entirely natural and nutrient-dense alga does just that; it can improve or help to prevent a wide range of health conditions.

You may have heard of spirulina before and want to learn more, or perhaps it is new to you entirely.

Either way, here we delve deep into the benefits of spirulina so that you can learn what this blue-green alga is good for.


What is Spirulina?

Spirulina is a type of algae, which is similar to seaweed. You can find these unique algae growing wild in freshwater or saltwater, and they can also be cultivated and grown in specially prepared pools.

Interestingly, despite its recent rise to fame, spirulina is not new. It is actually considered to be one of the first life forms on planet earth. The ancient Aztecs used it as a traditional health food source.

It is included in tablet or powder form in many superfood health blends or supplements in its own right.

You may also see spirulina listed in the product description as cyanobacteria or even spirulina platensis, but these are just other names for the same algae.

What Does Spirulina Do For Your Body?

Spirulina is an incredible multi-purpose supplement that can improve everything from your immune system to your blood pressure.

Spirulina supplements can be used to specifically target different health issues, such as raised cholesterol and hypertension, or as a general health booster to improve your overall wellbeing.

This blue-green alga can also be used as a simple way to increase our intake of vitamins, antioxidants, and protein, making it a valuable aid to a balanced diet.

Many of us struggle to consume the full range of nutrients we need for good health, so adding in spirulina can quickly increase our intake of many essential, health-promoting nutrients.

Evidence shows that spirulina really works (1).

There are many studies indicating spirulina may improve several health markers and reduce factors associated with chronic disease.

Therefore taking spirulina supplements is a research-backed way to maximize your health.

What Are The Health Benefits of Spirulina?

As you might expect from a superfood, there are many health benefits associated with taking spirulina regularly.

Here we explore the top ten benefits.

Extremely High in Many Nutrients

Spirulina is uniquely beneficial, as it contains many of the minerals and vitamins we can be lacking in our daily diets. Even if we eat lots of vegetables, it can be hard to get enough nutrient sources from our diet alone.

In particular, spirulina is a good source of Copper, which can balance out zinc supplementation to reduce an imbalance.

It also contains iron, which studies show up to 42% of pregnant women are deficient in. Spirulina may be the best source of plant-based iron, with many vegans running low in this vital mineral.

Although vegetables are healthy, they are not as high in iron as animal-based foods, meaning many plant-based women can benefit from an iron-rich supplement at various times in their lives.

Iron is essential for our red blood cells, and we can experience substantial fatigue if we become depleted. Luckily you can find over 11 percent of your daily iron requirements in less than a tablespoon of spirulina.

Spirulina also contains a range of B vitamins such as B1, B2, and B3, which contribute to energy metabolism and support the body in times of stress.

Studies show how essential B vitamins are for our nervous system. Therefore vegans can also benefit, as they tend to be depleted in B vitamins.

Aside from these vitamins and minerals, spirulina products are also a good source of protein, helping you access enough essential amino acids, which makes these supplements an excellent addition to an active lifestyle.

You only need a small amount of Spirulina powder (as little as a teaspoon) to increase your daily nutrient and protein intake, making it gram for gram one of the most nutritious diet supplements available.

Powerful Antioxidant and Anti-Inflammatory

Spirulina contains the essential fatty acid omega 3, which research has demonstrated can reduce harmful inflammation in the body. You only necessitate around a tablespoon to give you enough to get the benefits (2).

Therefore spirulina may reduce the negative effects of inflammation on the body, which, when chronic, can contribute to the development or progression of diseases such as heart disease, autoimmunity, and cancer.

Spirulina is also a source of gamma-linolenic acid, which can reduce harmful inflammatory damage to our DNA (3).

A study has shown that this type of algae also contains a unique antioxidant called phycocyanin, a potent protector against the kind of oxidative stress that can damage both our cells and our DNA over time (4).

As well as fighting the free radicals which are involved in oxidative stress damage, research shows phycocyanin can even inhibit the production of molecules associated with inflammatory activity.

As a bonus, spirulina also contains beta carotene, this is a type of carotenoid antioxidant, which can protect your eyes against age-related disease.

Boosts The Immune System

Research in both human and animal studies shows that spirulina consumption can enhance immune system activity by increasing the level of bacteria-fighting antibodies and other immune system cells.

Spirulina may therefore be helpful against infectious disease, and in particular, it can support age-related immune dysfunction, known as immunosenescence.

The high levels of protein and chlorophyll can improve immune function, and may also have merit in cases of autoimmune disease, where immune system activity is unhelpfully overactive.

Lowers Bad Cholesterol and Triglyceride Levels

Spirulina supplements can benefit people with elevated cholesterol in two key ways.

It can reduce the levels of bad LDL by as much as ten percent and increase the levels of good HDL cholesterol, both of which reduce the risk of heart disease (5).

As an additional benefit, the high antioxidant levels in spirulina can also prevent the potentially dangerous oxidation of LDL cholesterol correlated with increased heart disease risk.

In addition to altering cholesterol, spirulina may lower our triglycerides levels, which can improve blood lipids and help people at risk of cardiovascular conditions.

Helps To Remove Heavy Metals And Detox

In experiments, spirulina platensis can help clear heavy metal toxicity from the body, which has a beneficial impact on the human body.

Metals such as mercury, lead, and arsenic can cause liver damage and may deplete our stores of vital nutrients. Therefore consuming spirulina supplements can help the body detox these metals (6).

One study concluded that spirulina’s antioxidant properties enable it to eliminate the heavy metals we are exposed to every day in our drinking water.

Likely, spirulina’s chlorophyll content is also partly responsible for its ability to help cleanse the body of these harmful toxins.

Improves Muscle Strength and Endurance

Taking spirulina products may produce unique exercise benefits by enhancing energy levels and reducing activity-induced fatigue.

A key study in this area established that spirulina could reduce the oxidative damage which causes muscle fatigue post-exercise, therefore increasing physical endurance capacity and exercise performance (7).

By reducing fatigue, spirulina has been shown in a study to improve muscle strength, making it excellent pre and post-workout, which explains its recent popularity in the world of fitness.

Reduces Blood Pressure

One of the best health benefits of spirulina is its role in reducing blood pressure, which affects our risk of multiple diseases.

A study showed spirulina reduced high blood pressure in otherwise healthy individuals when taken at a higher dose, around 4-5 grams per day (8).

It has even been shown to lower blood pressure in people with normal levels, partly due to its potent antioxidant properties, which support our blood vessels. It is also a valuable source of blood pressure-lowering mineral potassium.

A study has shown that spirulina, like other superfood algae such as chlorella, can increase the amount of blood vessel relaxing nitric oxide, which can reduce blood pressure (9).

Helps With Blood Sugar Control

Studies involving animals have shown spirulina can significantly reduce blood sugar levels, offering protection against diabetes type 2 (10).

Improved blood sugar maintenance can also help us manage our weight and keep our energy levels balanced throughout the day.

There is also a wealth of evidence in humans to suggest a positive effect on raised HBA1C levels, an indicator of prediabetes or diabetes type 2 (11).

One of the other effects of spirulina is that it can reduce cravings, damaging your blood sugar control. This is because it has such a high level of different proteins.

Helpfully, this also means that taking spirulina doesn’t have any detrimental effect on your body weight.

Additionally, another study suggests it is the fiber content in spirulina that may be responsible for lowering glucose absorption, making it a great overall aid in blood sugar control.

Improves Symptoms of Allergies

Spirulina appears to improve conditions linked to an immune overreaction such as allergic rhinitis, as just 2 grams of spirulina taken daily improved symptoms of nasal allergy (sneezing, congestion, and irritation) when compared to a placebo group (12).

One study showed that the regular ingestion of spirulina reduces histamine, which is the substance responsible for the symptoms of various seasonal allergies to pollen and allergic reactions to dust mite or pet hair (13).

Other possible benefits of spirulina include reduced nasal inflammation, a common side effect of allergic rhinitis.

The high quantities of multiple antioxidants, which are found in spirulina, help to dampen down both the immune and inflammatory activity involved in allergic rhinitis, but only when taken frequently, ideally on a daily basis.

Has Anti-Cancer Properties

Evidence supports a potential role for spirulina in preventing cancer progression.

A study involving people taking 1 gram of spirulina daily demonstrated a significant reduction in the size of oral cancer lesions. More studies are needed to confirm its effectiveness, but research so far is very encouraging (14).

Unique anti-cancer properties of superfoods such as spirulina include its high amounts of phycocyanin, which acts as a toxin towards cancerous cell groups.

Evidence also suggests spirulina’s anti-cancer effects include immune function modulation and anti-inflammatory activity, as many chronic diseases such as cancer are rooted in persistent unresolved inflammation.

How To Take Spirulina

Spirulina is safe to take in doses of up to 19 g daily (for up to two months), but most clinical studies have used amounts ranging from 1-10 g per day. Bear in mind that higher doses will contain a lot of protein, so you may need to adjust your dietary intake accordingly.

For health maintenance or general wellbeing, lower dosages of 1-5 g appear adequate.

Whereas if you are taking superfoods such as spirulina or chlorella to help manage or treat a particular condition, such as high blood pressure or elevated blood sugar, then an amount of 5-10 g may be more effective.

You can take spirulina in several different forms.

For example, you can find many superfood powders containing cyanobacteria. You can then add to various juices or smoothies to help disguise the taste if you are not keen on the naturally earthy flavor.

Of course, you can also find spirulina powder on its own if you don’t wish to take other ingredients with it too.

Taking tablets is another good option, as they still provide all the beneficial effects of spirulina, but they can also be easily taken with just a little water.

Check for any unnecessary added ingredients such as fillers and sugars, ideally, aim to buy the purest supplement possible.

You can take spirulina at any time of day, but many people choose to take their supplements in the morning in order to set them up for the day.

Consider splitting the doses evenly throughout the day if you are taking larger quantities and consuming with or near other foods to increase nutrient absorption and reduce any risk of digestive discomfort.

Spirulina will immediately increase your level of nutrients, offering you sources of magnesium, calcium, and manganese straight away.

However, for some of the other health benefits of spirulina, expect it to take a little longer to see or feel the impact, especially if you are only taking around 1 gram of spirulina.

It may take longer to improve health markers such as blood pressure and cholesterol.

What Are The Side Effects of Spirulina?

Spirulina is a popular supplement that has been proven safe and side-effect-free for the majority of people.

Spirulina is a natural alga, and therefore can be considered a food-based supplement and safe addition to a healthy diet.

For a few people, minor side effects may be experienced, especially if you take very high doses to begin with.

Such effects may include little stomach discomfort or headaches, but these effects can be reduced if you take spirulina alongside food or drink.

For most people, the benefits of spirulina vastly outweigh any slight side effects or temporary discomfort. There is a specific contraindication for taking spirulina. Suppose you have a condition known as phenylketonuria.

In that case, this blue-green algae may be harmful to you, as it contains phenylalanine levels, which people with such conditions should avoid.

Also, if you are on any specific medications, such as metformin for diabetes, check with your doctor if you have any concerns.

It is worth mentioning that not all spirulina products are made equal. You want to make sure your spirulina powder or tablets have been tested for any contaminants that may be unhealthy, including any traces of heavy metals.

Picking high-quality and reputable brands should help with this.

The Takeaway

This particular type of blue-green algae is a precious and unique addition to your daily diet.

Key spirulina benefits include protection against diabetes, a reduction in unhealthy toxins, improved blood triglycerides, and cholesterol levels.

Taking spirulina every day is an easy way to increase your Vitamin C and Vitamin B12, protein, and potassium.

Whether you take 1 gram of spirulina, or many, either with chlorella or in smoothies, spirulina may improve your health and wellbeing in many different ways.


Is it safe to take spirulina every day?

Yes, spirulina may be one of the safest supplements around.

Most people will not experience any noticeable issues, to reduce your risk, try to take your spirulina with food or drink.

Also, if you are new to taking spirulina, start with smaller quantities before increasing your dosage to several grams of spirulina.

What’s the difference between green and blue spirulina?

Green spirulina is the whole form of the algae, whereas the blue version is an extract.

The blue version contains many of the benefits but has less of a “fishy taste.”

Does spirulina contain heavy metals?

Not if you pick a good quality form of spirulina that is tested for purity.

This blue-green algae will help your body detox from the heavy metals you may ingest via other food and drink.

Can moringa and spirulina be taken together?

Yes, it is definitely even thought that moringa and spirulina work even better when combined together.

You often see this combination together in superfood blends with other health-promoting ingredients.