Spirulina Nutrition: The Amazing Nutritional Benefits of Spirulina

This pond-scum-turned-superfood has burst onto the health food scene in..

Spirulina Nutrition: The Amazing Nutritional Benefits of Spirulina

This pond-scum-turned-superfood has burst onto the health food scene in a big way. With fans claiming it’s everything from a complete protein to a cure for cancer.

Naturally, when one food source is said to do all that and more, it piques my interest. I decided to take a closer look at spirulina to see if it lives up to the hype.

What Exactly Is Spirulina?

This spiral shaped micro-algae grows naturally in warm. Alkaline lakes in Africa and Central and South America, as well as in saltwater. It’s also cultivated and harvested in man made reservoirs.

Spirulina, with its rich blue green color, is said to be quite similar to the nutrient rich sea vegetables like dulse, kelp, nori, kombu, wakame, and chlorella.

From Aztecs To Astronauts…

For an algae, it has a pretty interesting history I have to say. It was said to be the primary protein source of the Aztecs in the 14th century, as well as for those living around Lake Chad in Central Africa.

At the United Nations World Food Conference of 1974. Spirulina was declared as ‘the best food for the future’ and is still being looked at as a way to combat malnutrition in developing countries.

And, in the late 1980s, NASA proposed spirulina as one of the main foods to be cultivated during long term space missions. Because of its high nutritional content and ability to survive almost anywhere.

With endorsements from NASA and the UN, it’s pretty hard not to be impressed by spirulina. Let’s have a look at its nutritional profile and some of the health benefits it may bring.

The Secret Behind Its Unique Coloring

The blue green color of spirulina is caused by the presence of phycocyanin – a pigment that may have several amazing health benefits. 

Including supporting the brain and heart, and protecting against oxidative stress.

Oxidative stress is the imbalance between the production of free radicals and the ability of the body to counteract their harmful effects.

These free radicals cause everything from neurodegenerative diseases to cancers and chronic fatigue. 

So it’s essential our body is able to fight them through adequate levels of antioxidants.

Studies have confirmed spirulina’s high antioxidant and anti-inflammatory properties in both humans and animals.

Experts believe that it is the phycocyanin that gives spirulina its amazing antioxidant properties, in addition to its brilliant blue green color.

What’s interesting about phycocyanin is that this particular antioxidant is found only in spirulina, and makes up 16% of the algae’s total weight. In the fight against oxidative stress, spirulina might be a powerful weapon to have.

A Complete Protein

It seems like the Aztecs were on to something using spirulina to help meet their protein needs. Not only does it contain 50% to 70% protein by weight. 

It also contains all of the essential amino acids. I can see now why vegetarians and vegans often supplement with spirulina.

What’s confusing is that some sources say you’d need to eat a lot of spirulina to get your daily requirement of protein, whereas others state that just two tablespoons are adequate to substitute protein in a meal.

I have to say I’m skeptical of claims that you can replace a whole portion of your meal with a mere scoop or two of powder.

It would work out pretty expensive too, this algae costs about 30 times as much as meat or milk per gram.

While it might have a high protein content, it’s just not practical in terms of cost and volume needed.

Instead, I suggest non meat eaters get their protein from other plant based sources like nuts, legumes, quinoa, and whole grains, in addition to supplementing with spirulina if they wish.

Rich In Vitamins & Minerals

Being a seafood, spirulina is a great natural way to get iodine into your diet, which is important for a well functioning thyroid, a strong metabolism and healthy brain.

The American Thyroid Association lists iodized salt as one of the best sources of iodine (along with dairy, meat, seafood, and eggs).

If you’re not keen on adding salt to your diet, and don’t eat animal products, then spirulina may be an alternative way to meet your iodine needs.

This algae has about the same amount of calcium, phosphorous, and magnesium as milk, is a good source of vitamin K, pantothenic acid (B5), and potassium, and a very good source of thiamin (B1), riboflavin (B2), niacin (B3), iron, copper, and manganese.

While you can see that spirulina is a rich source of B vitamins, many sources also claim it’s exceptionally high in B12.

However, I’ve discovered mixed findings on this with studies suggesting that our bodies don’t absorb this particular form of B12 well, if at all.

Because a B12 deficiency can cause so many undesirable symptoms, from disturbed vision. 

To depression, and declining mental abilities, it is important spirulina is not relied on as a sole source of B12. Instead, try meat, salmon, dairy, eggs, or fortified cereals and non-dairy milk.

(And did you know beer is also a source of B12, among other vitamins?)

An Antidote To Poisoning?

Perhaps one of the most fascinating studies I came across on Spirulina was its ability to treat arsenic poisoning.

Because millions of people consume high concentrations of arsenic through their drinking water.

Bangladeshi researchers conducted a three month hospital based study, where spirulina was given to 34 patients of chronic arsenic poisoning, while 17 received placebos.

Results show that spirulina extract plus zinc twice daily for 16 weeks contributed to a significant improvement of symptoms.

While I certainly wouldn’t rely on spirulina if I accidently ingested a load of arsenic, I think this study is interesting because it indicates that spirulina is a powerful detoxifier.

This is most likely because of its high levels of chlorophyll, which has the ability to remove toxins from the blood and cleanse key elimination systems like your bowel and liver.

I’ve already talked about chlorophyll and its powerful effects, which you can read about in my post on wheatgrass – another amazing green superfood.

Fight Allergies

Are you one of the millions that suffer from allergies to pollen, dust mites, mold, pet dander, or other irritants that you inhale?

Stuffy noses, watery eyes, and itchy throats are nothing to be sneezed at (sorry, couldn’t resist!), but before you start with the nasal sprays and antihistamines, why not give spirulina a go?

Animal studies suggest that spirulina stops the release of histamine, which contributes to symptoms of allergic rhinitis.

Similar studies on humans found that spirulina consumption significantly improved symptoms like nasal discharge, sneezing, nasal congestion and itching, when compared with the placebo group.

Regulate Blood Pressure

High blood pressure is a serious medical condition that leads to an increased risk of dying from heart attack or stroke. It’s so important to regulate your blood pressure levels though healthy diet, lifestyle choices, and exercise.

There may be no harm in getting a little help from a superfood too.

According to a Mexican study, 4.5 g of spirulina daily was shown to regulate blood pressure in both men and women in just six weeks, and this was without any other dietary changes!

Of course, you know I’d never recommend you simply eat some algae while still stuffing your face with cheesy pizza and greasy fries.

Whether you decide to add spirulina to your diet or not, a balanced diet and regular exercise is one of the best ways to feel and look great.

Lowers Chance of Stroke

In the study above, researchers also discovered that the spirulina supplementation lowered intimal aorta surface by 33% to 48%, which suggests that it can prevent atherosclerosis and subsequent stroke. 

It’s important to remember that this clinical trial was conducted on animals that were still eating a HCD, and it highlights that regular spirulina consumption can literally reverse the damage done by eating a poor diet.

You can only imagine the heart health benefits that would be experienced in those individuals who have a balanced diet!

Manage Cholesterol

I’ve talked about cholesterol before, so you’ll know it’s important to ensure the ‘good’ and the ‘bad’ cholesterol are balanced. If not, you could be on your way to a heart attack or stroke.

Sure, there are medications out there that help lower your cholesterol, but they aren’t without side effects. How does muscle pain, liver damage, digestive problems, and memory loss sound?

Wouldn’t it make much more sense to balance cholesterol levels through diet, exercise, and nutritional supplements? Well, spirulina might just be one such supplement.

Elderly patients (aged 60+) were found to have lower cholesterol levels after consuming 8 grams of spirulina a day for 16 weeks.

Another study found that spirulina may be beneficial in preventing atherosclerosis (a hardening of the arteries caused by high cholesterol levels) and reducing risk factors for cardiovascular diseases.

A Cure For Cancer?

One of the leading causes of death worldwide, cancer is downright scary. So naturally, anything that claims it can cure or prevent this illness is going to grab my attention.

In my research, I came across numerous claims and studies relating to spirulina’s effect on cancer.

In one such study, taking spirulina seemed to reduce precancerous lesions in people who chewed tobacco, when compared with the placebo group.

Another study has shown it may inhibit pancreatic cancer growth.

Of course, much more research is needed before we can know for sure if spirulina is the cancer killer some claim it is. Until then, play it safe and do what the doctor orders.

When it comes to cancer prevention, make sure your body is as healthy as it can be, cut out sugars, simple carbs, and processed foods, and eat plenty of antioxidant rich organic fruits and vegetables.

Be sure to check out my post on The Best & Worst Cooking Oils to Avoid Toxins and Prevent Cancer.

Boost Immunity

If you pick up every cough and cold going around, then this may be of interest to you.

The superfood spirulina has been found to enhance immune system function and suppress the development of viral infections.

This has been shown to be true even in the immune function of senior citizens and in animal studies.

It’s thought that the potent nutrients in spirulina, known as polysaccharides, are responsible for helping with this boost in immunity.

The bright blue antioxidant, phycocyanin, which I mentioned earlier, is thought to help increase the number of white blood cells in the body.

In turn, these white blood cells play a vital role in our immune system, helping to fight off foreign invaders, produce antibodies and kill bacteria.

Speeds Up Weight Loss

Diets high in nutrient-dense protein-rich foods like spirulina promote weight loss and low-fat stores through a variety of mechanisms.

Because it takes more energy to metabolize, for example, eating protein helps maintain lean tissue and contributes to fat burning.

It can also curb hunger and overweight people seem to benefit the most. To maximize this benefit. Try eating your high protein spirulina in the morning or during midday instead of at night.

Alleviates Sinus Issues

Known as allergic rhinitis, spirulina benefits the body by reducing the inflammation that causes people to experience sinus problems, according to numerous studies. 

Compared to placebo trials, spirulina is effective at reducing itching, nasal discharge, nasal congestion and sneezing.

Improve Memory & Academic Performance

Who would have thought a little pond weed could help you get better grades? Well, studies indicate that spirulina can actually improve both mental health and cognitive ability.

When 549 school children were given 2 g of spirulina once daily for two months, their academic performance actually improved by 10%, when compared with other children.

While researchers couldn’t say for certain that the spirulina caused the improved performance. 

They do believe it played a role, possibly by increasing the amount of L-tryptophan, an amino acid that is a precursor to the neurotransmitter serotonin.

Spirulina has also been shown to prevent memory loss by reducing oxidative damage, and may protect the brain from degenerative diseases, like Parkinson’s and Alzheimer’s.

Another study I found was comparing spirulina with two other amazingly antioxidant rich foods – spinach and blueberries – to understand their neuroprotective effects.

Guess which one came out on top?

That’s right, spirulina. It was found to have the highest neuroprotective effect, possibly due to its ability to eliminate free radicals and reduce inflammation.

Given how nutrient dense blueberries and spinach are. 

That’s no mean feat and definitely points to spirulina being worthy of its ‘superfood’ status.

I’d definitely rank it up there with some of my other favorite superfoods, like kale and green tea, in terms of health benefits.

Hawaiian Spirulina Pacifica

As one of the most nutritious, concentrated whole foods known to humankind, Hawaiian Spirulina Pacifica provides more nutrition gram per gram than any other spirulina on the market.

Just one 3-gram serving, for instance, contains:

  • 60% protein and an excellent source of vitamins A, K1, K2, B12 and iron, manganese and chromium
  • A rich source of health-giving phytonutrients such as carotenoids, GLA, SOD and phycocyanin
  • 2800% more beta-carotene than carrots
3900% more iron than spinach

  • 600% more protein than tofu
  • 280% more antioxidants than blueberries


This nutritional profile leads to a number of health benefits, including:

  • Strengthened immune system
  • Boosted energy level
  • Supported cellular health
  • Cardiovascular, eye and brain health


How To Take Spirulina

Are you sold on the amazing nutritional benefits of spirulina yet?

If so, you’re probably wondering how to take it.

You can add it to just about anything – from energy bars and smoothies, to guacamole and pesto. As with any new supplement, start slowly and work your way up to a teaspoon or two per day.

I have to warn you…it tastes pretty nasty. Even though I’ve never drank actual pond scum before, this is exactly how I would expect it to taste. I prefer to just add my spirulina to a little water and get it over and done with.

You can also get it in capsule form, which might be a wiser choice if you can’t get past that scummy taste, smell, and feel.

If you have a seafood allergy then you should steer clear of spirulina.

People with medical conditions like the rare PKU (phenylketonuria) or hypothyroidism should consult a doctor before taking it. 

As should those who are pregnant, nursing or on any medications.

How To Choose A Brand

Whatever you do, go with a reputable brand and only buy organic.

Like other algae, spirulina can absorb heavy metals from the waters where it grows. 

And can also be contaminated with toxic substances called microcystins.

When researchers tested eight Chinese and foreign brands of spirulina, they found excessive amounts of lead in six.

Lead causes long term harm and increases the risk of high blood pressure and kidney damage. It’s also extremely dangerous to children’s developing systems.

Furthermore, Dr. Mercola recommends avoiding any sea vegetables (including spirulina) that came from Japan and its nearby waters since March 2011.

He claims they may be contaminated with radiation from the Fukushima nuclear incident.

There’s not much point in taking a supplement with so many reported health benefits if you’re simultaneously going to be pumping your body full of toxins. 

And who knows what else, so definitely be careful what you buy.

Overall, spirulina seems to be a pretty healthy and even impressive supplement to take in terms of its antioxidant power and vitamin and mineral load.

Of course, I’m not sold on its cancer curing abilities, and would be wary of considering it as a sole protein source.

But, by all means, supplement with spirulina if you wish, it seems to have enough health benefits to warrant a place in a healthy, well balanced diet.

Spirulina Nutrition Facts

The major reason why I prefer spirulina to chlorella? Because it’s arguably the most nutrient-dense food on the planet.

Taken as an average of different spirulina species, just one ounce contains the following nutritional content:

  • Calories (81)
  • Protein (39g)
  • Dietary fiber (1g)
  • Sugars (.9g)



  • Total fat (3% Daily Value)
  • Saturated fat (4%)
  • Omega-3 fatty acids (230 mg)
  • Omega-6 fatty acids (351 mg)



  • Copper (85%)
  • Iron (44%)
  • Manganese (27%)
  • Magnesium (14%)
  • Sodium (12%)
  • Potassium (11%)
  • Zinc (4%)
  • Phosphorus (3%)
  • Calcium (3%)
  • Selenium (3%)



  • Riboflavin (60%)
  • Thiamin (44%)
  • Niacin (18%)
  • Pantothenic Acid (10%)
  • Vitamin K (9%)
  • Vitamin E (7%)
  • Folate (7%)
  • B6 Vitamin (5%)
  • C Vitamin (5%)
  • A Vitamin (3%)


Spirulina Possible Side Effects

It’s absolutely critical to make sure that the quality and purity of the spirulina that you consume is of the highest standards.

Particularly, like anything that comes from the sea, be certain to only purchase blue-green algae that is free from contamination. According to WebMD, contaminated spirulina can cause the following:

  • Liver damage
  • Stomach pain
  • Nausea
  • Vomiting
  • Weakness
  • Thirst
  • Rapid heartbeat
  • Shock, and even death


Also, some sources suggest that pregnant women and children should not consume algae. Contact your natural health care provider to confirm whether or not you should be supplementing with spirulina.

Daniel Messer, RNutr, CPT

We eat clean, are always motivated and helpout beginners in need. We sell guides on Cutting, Bulking and Muscle Building. Checkout our website!

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