Table of ContentsView AllTable of ContentsNutritionPotential BenefitsSide EffectsHow to Use SafelyAdding Spirulina to Your Diet
Table of ContentsView All
View All
Table of Contents
Nutrition
Potential Benefits
Side Effects
How to Use Safely
Adding Spirulina to Your Diet
Spirulina is a blue-green algae cultivated from lakes or farmed in ponds. Its nutritional benefits and antioxidant properties may help with health conditions likeulcerative colitis, or offer a boost when managing weight, cholesterol levels, skin health, and more.
Long used in traditional medicine,spirulinais usually taken as a supplement and is available in powder, capsule, tablet, and liquid form.More research is needed, however, to identify and understand the potential health benefits of spirulina.
In the United States, the Food and Drug Administration (FDA) does not regulate supplements the way it regulates prescription drugs. That means some supplement products may not contain what the label says. Whenchoosing a supplement, look for independently tested products and consult a healthcare provider, registered dietitian nutritionist (RD or RDN), or pharmacist.
Verywell / Getty Images
Spirulina is a rich source of protein and severalfatty acids, vitamins, and minerals. It also containsphycocyanins(a protein with a bluish pigment and antioxidant properties).
One tablespoon (seven grams) of spirulina contains the following nutrients:
Since spirulina comes from bacteria (cyanobacteria), it may be considered a protein source for vegans. Spirulina contains more protein than most vegetables.However, it lacks high enough levels of some amino acids that your body needs to function at its best.
Some people claim that spirulina has a range of health benefits. More extensive studies are needed before recommending spirulina for any condition. However, the following explores what science says about spirulina’s effects on different health outcomes.
1. Ulcerative Colitis
Ulcerative colitis is an inflammatory bowel disease (IBD) that mainly impacts the large intestine. It can increase the risk of anemia and other nutrient deficiencies, colon cancer, and other conditions.
Anemia (low red blood cell function) is a serious condition that can cause an array of symptoms, from poor sleep to anxiety. A study using 1 gram (g) a day of spirulina for eight weeks in people with UC suggested spirulina benefited their labs associated with anemia.
Spirulina also improved antioxidant capacity status and health-related quality of life in patients with UC.
Further study is needed to confirm these results.
2. Antioxidant Capacity
According to research, 1 to 8 grams of spirulina per day increasedsuperoxide dismutase(SOD) and total antioxidant capacity (TAC).Antioxidant effects include preventing cellular damage and protecting overall health. They were greater when people took 5 grams of spirulina or more daily.
However, you may not want to rely on spirulina alone to increase your TAC. Many foods are great sources of antioxidants and can help reduce inflammation. To increase antioxidants in your diet, try including various nutrient-dense foods, such as:
Eating a variety of fruits and vegetables has been linked to improved emotional well-being, vision health, and immune function.Keep in mind that these foods do not have to be organic.
3. Athletic Benefits
Intense exercise can impact physical processes such as inflammation, immune function, and performance.Spirulina has been studied for its impact on these factors and outcomes.
A different study in cyclists suggested that 6 grams of spirulina a day for 14 days improved hemoglobin concentration. However, it did not significantly improve physical performance.
4. Blood Pressure
The most significant blood pressure-lowering occurred in people with high blood pressure.
5. Blood Sugar Control
Rapidly changing, uncontrolled blood sugar levels over time can negatively impact people with type I or 2 diabetes, eating disorders (includingdiabulimia,an intentional misuse of insulin to manipulate weight), and more.
Over time, uncontrolledblood sugar spikescan lead to complications such as:
A study published in 2023 shows that spirulina lowered blood sugar levels.It may have additive effects with metformin, a medication used to lower blood sugar in people with type 2 diabetes.
Results showed that 2 grams a day of spirulina (S. platensis) achieved these results compared with metformin alone:
The protein and fiber content of spirulina may be responsible. Phycocyanin may lower inflammation, which may help reduce complications. However, scientists are still figuring it out.
How Can a Certified Diabetes Care and Education Specialist (CDCES) Help?A team that includes a registered dietitian nutritionist (RD or RDN), particularly a Certified Diabetes Care and Education Specialist (CDCES), can help you explore your food, exercise habits, medication, and more. Managing blood sugar can be challenging and you don’t have to do it alone.
How Can a Certified Diabetes Care and Education Specialist (CDCES) Help?
A team that includes a registered dietitian nutritionist (RD or RDN), particularly a Certified Diabetes Care and Education Specialist (CDCES), can help you explore your food, exercise habits, medication, and more. Managing blood sugar can be challenging and you don’t have to do it alone.
6. Cancer
Very few well-designed human studies have examined spirulina’s effects on cancer. Some studies have been conducted in the laboratory (in vitro) and on animals. However, more studies are needed to examine its impact on humans.
7. Cholesterol Levels
Your body needs cholesterol to function properly. The two main kinds are low-density lipoprotein (LDL), or “bad” cholesterol, and high-density lipoprotein (HDL), or “good” cholesterol.
A collection of studies on cholesterol levels found that spirulina:
Healthcare providers generally do not suggest spirulina as a first-line treatment for lowering cholesterol and may suggestmedicationto manage your condition. While supplements may help, larger clinical trials and more research are needed to confirm benefits for managing cholesterol.
8. Liver Health
Your liver supports your body’s natural detoxifying processes, digestion, immune system, and more. Most studies of spirulina’s effects on the liver are done in animals or the lab.
However, a 2024 review of studies suggests a role in preventing lipid buildup in the liver.More research is needed to understand any benefits or protective effects of spirulina.
9. Metabolic Syndrome
Scientists have studied spirulina’s effects onmetabolic syndrome.Metabolic syndrome happens when a person has the following:
Metabolic syndrome can negatively impact your health and increase your risk of heart attack, stroke, and type 2 diabetes.
As with some of the other research, a collection of studies suggested that spirulina could help lower high blood pressure, high blood sugar, and high cholesterol.
More studies are needed to confirm whether spirulina may be a helpful addition to other methods of managing metabolic syndrome, including healthy eating, exercise, and medications.
Studies in people withmetabolic syndrometaking 1 to 8 grams of spirulina per day showed reduced blood sugar and insulin levels.
10. Obesity
Scientists reviewed spirulina’s effects on weight management in people withobesity.
Spirulina was associated with a weight loss of 4.55 pounds in participants with obesity and a weight loss of 2.82 pounds in people diagnosed as overweight.
However, clinically speaking, these results are not enough to make a solid recommendation for using spirulina for obesity treatment.
How Can a Board Certified Specialist in Obesity and Weight Management (CSOWM) RD/RDN Help?Consider working with a team that includes a registered dietitian nutritionist (RD or RDN) and perhaps one that’s a Board Certified Specialist in Obesity and Weight Management (CSOWM). They can help develop an individualized plan to improve your overall health.
How Can a Board Certified Specialist in Obesity and Weight Management (CSOWM) RD/RDN Help?
Consider working with a team that includes a registered dietitian nutritionist (RD or RDN) and perhaps one that’s a Board Certified Specialist in Obesity and Weight Management (CSOWM). They can help develop an individualized plan to improve your overall health.
11. Skin Health
Although more research is needed, spirulina may be good for the skin due to the many bioactive compounds it contains. It is thought that spirulina may:
Spirulina is generally safe, but some people have reported the following with its use:
An allergic reaction such as rash, swelling, throat swelling, or other symptoms ofanaphylaxis(severe allergic reaction) may be possible in those allergic to spirulina.
If you experience side effects, stop using spirulina and contact your healthcare provider immediately.
People choosing spirulina supplements need to consider the correct dosage, as well as side effects, potential drug interactions, and other concerns.
Precautions
When considering spirulina use, be aware of the following:
People diagnosed with certain conditions also may need to avoid spirulina. These conditions include disorders affecting how the body uses proteins or amino acids, such asphenylketonuria(PKU) ormaple syrup urine disease(MSUD).They also include autoimmune conditions, such as lupus and multiple sclerosis.
Dosage
There’s currently no recommended “effective” dosage of spirulina, and manufacturer recommendations might vary.Studies have used 1 to 10 grams a day for up to six months and 19 grams a day for up to two months, with a relatively good safety profile in people with different conditions.Less is known about the long-term use of spirulina.
As a general guideline, don’t take more than the amount listed on the product label. A standard dose is 4 to 6 tablets (500 mg each) per day.
The types of blue-green algae used in spirulina supplements are typicallySpirulina maxima,Spirulina platensis, orAphanizomenon flos-aquae. Keep in mind that no supplement is intended to treat, cure, or prevent disease.
Interactions
The following are interactions to consider when taking spirulina:
It is essential to carefully read a supplement’s ingredient list and nutrition facts panel to know which ingredients and how much of each ingredient is included. Please review this supplement label with your healthcare provider to discuss potential interactions with foods, other supplements, and medications.
How Do I Add Spirulina to My Diet?
Several ways to include spirulina in your diet include the following:
Not everyone tolerates or likes the taste of spirulina, which is described as earthy or fishy. If you don’t like the taste, consider mixing it with foods with intense taste profiles (e.g., garlic-heavy pesto).
Summary
Spirulina is an edible blue-green algae that contains several important nutrients.
Research shows spirulina has some effects on increasing antioxidant levels in the body and reducing blood pressure, blood sugar, and cholesterol levels.
However, the most effective way to manage chronic conditions is to address lifestyle habits, such as your eating patterns and activity level, which can significantly affect your health and well-being.
Working with your healthcare provider and a registered dietitian nutritionist (RD/RDN) is one way to achieve your nutrition and health goals.
25 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Ansari R, Foroughinia F, Dadbakhsh AH, Afsari F, Zarshenas MM.An Overview of Pharmacological and Clinical Aspects ofSpirulina.Curr Drug Discov Technol. 2023;20(2):e291122211363. doi:10.2174/1570163820666221129141217
U.S. Department of Agriculture.Spirulina.
Harvard Health Publishing.By the way, doctor: Is spirulina good for you?
Moradi S, Foshati S, Poorbaferani F, et al.The effects of spirulina supplementation on serum iron and ferritin, anemia parameters, and fecal occult blood in adults with ulcerative colitis: A randomized, double-blinded, placebo-controlled trial.Clin Nutr ESPEN. 2023;57:755-763. doi:10.1016/j.clnesp.2023.08.019
Fumery M, Singh S, Dulai PS, et al.Natural history of adult ulcerative colitis in population-based cohorts: a systematic review.Clin Gastroenterol H. 2018;16:343-356.e3. doi:10.1016/j.cgh.2017.06.016
Naeini F, Zarezadeh M, Mohiti S, et al.Spirulina supplementation as an adjuvant therapy in enhancement of antioxidant capacity: a systematic review and meta-analysis of controlled clinical trials.Int J Clin Pract. 2021;75(10):e14618.
Harvard T.H. Chan School of Public Health.Antioxidants.
Valero-Vello M, Peris-Martínez C, García-Medina JJ, et al.Searching for the Antioxidant, Anti-Inflammatory, and Neuroprotective Potential of Natural Food and Nutritional Supplements for Ocular Health in the Mediterranean Population.Foods. 2021 May 28;10(6):1231. doi:10.3390/foods10061231
Zhang Y, Zhang Y, Wu W, et al.Effects on spirulina supplementation on immune cells’ parameters of elite college athletes.Nutrients. 2022;14(20):4346. Published 2022 Oct 17. doi:10.3390/nu14204346
Ali Y, Aubeeluck R, Gurney T.Fourteen-days spirulina supplementation increases hemoglobin, but does not provide ergogenic benefit in recreationally active cyclists: A double-blinded randomized crossover trial.J Diet Suppl. 2024;21(3):261-280. doi:10.1080/19390211.2023.2263564
Machowiec P, Ręka G, Maksymowicz M, et al.Effect of spirulina supplementation on systolic and diastolic blood pressure: systematic review and meta-analysis of randomized controlled trials.Nutrients. 2021;13(9):3054.
Matthews J, Herat L, Rooney J, Rakoczy E, Schlaich M, Matthews VB.Determining the role of SGLT2 inhibition with Empagliflozin in the development of diabetic retinopathy.Biosci Rep. 2022;42(3):BSR20212209.
Karizi SR, Armanmehr F, Azadi HG, et al.A randomized, double-blind placebo-controlled add-on trial to assess the efficacy, safety, and anti-atherogenic effect of spirulina platensis in patients with inadequately controlled type 2 diabetes mellitus.Phytother Res. 2023;37(4):1435-1448. doi:10.1002/ptr.7674
da Silva MRO. da Silva G, da Silva ALF, de Lima LRA, Bezerra RP, de AV Marques D.Bioactive compounds ofarthrospiraspp. (Spirulina)With potential anticancer activities: a systematic review.ACS Chem Biol. 2021;16(11):2057-2067. doi:10.1021/acschembio.1c00568
Rahnama I, Arabi SM, Chambari M, et al.The effect of Spirulina supplementation on lipid profile: GRADE-assessed systematic review and dose-response meta-analysis of data from randomized controlled trials.Pharmacol Res. 2023;193:106802. doi:10.1016/j.phrs.2023.106802
DiNicolantonio JJ, Bhat AG, OKeefe J.Effects of spirulina on weight loss and blood lipids: a review.Open Heart. 2020 Mar 8;7(1):e001003. doi:10.1136/openhrt-2018-00100
Sokary S, Bawadi H, Zakaria ZZ, Al-Asmakh M.The Effects of Spirulina Supplementation on Cardiometabolic Risk Factors: A Narrative Review.J Diet Suppl. 2024 Jan 22:1-16. doi:10.1080/19390211.2023.2301366
Hamedifard Z, Milajerdi A, Reiner Ž, et al.The effects of spirulina on glycemic control and serum lipoproteins in patients with metabolic syndrome and related disorders: a systematic review and meta-analysis of randomized controlled trials.Phytother Res. 2019;33(10):2609-2621.
Yousefi R, Saidpour A, Mottaghi A.The effects of Spirulina supplementation on metabolic syndrome components, its liver manifestation and related inflammatory markers: a systematic review.Complement Ther Med. 2019;42:137-144.
Moradi S, Ziaei R, Foshati S, et al.Effects of Spirulina supplementation on obesity: a systematic review and meta-analysis of randomized clinical trials.Complement Ther Med. 2019;47:102211.
Ikeda IK, Sydney EB, Sydney ACN.Potential application of Spirulinain dermatology.J Cosmet Dermatol. 2022 Oct;21(10):4205-4214. doi: 10.1111/jocd.14997
MedlinePlus.Blue-Green Algae.
Icahn School of Medicine at Mount Sinai.Spirulina.
Meet Our Medical Expert Board
Share Feedback
Was this page helpful?Thanks for your feedback!What is your feedback?OtherHelpfulReport an ErrorSubmit
Was this page helpful?
Thanks for your feedback!
What is your feedback?OtherHelpfulReport an ErrorSubmit
What is your feedback?
