Chlorella: Benefits, Dosage, Side Effects & How to Take It

Stir a spoonful of chlorella powder into a glass of water and the water turns a deep, grassy green. That color is chlorophyll, and chlorella is packed with it: chlorella powders tested in Germany averaged 1.8 to 1.9 grams per 100 grams, depending on the species.8 Under a microscope, the powder is a mass of single cells, each one a freshwater green alga with a nucleus, like the cells of a plant.1

In my approach, chlorella has two roles. It's a concentrated green food, with iron, folate and vitamin D2 in a few grams, and it's one of the binders I like best for an ongoing detox, along with pectin.8129

Human trials have tested it for cholesterol and fatty liver,34 and Japanese studies followed women who took chlorella through pregnancy, measuring anemia and the dioxins in their breast milk.1011

Did you know?

• Chlorella vulgaris was first described in 1890 by the microbiologist and botanist Martinus Willem Beijerinck.1

• More than 20 species of chlorella have been described, with over 100 strains.1

• Of 15 microalgae powders analyzed in a German lab, only the chlorella powders carried vitamin D2, which chlorella can make from a sterol called ergosterol when it grows in sunlight.81

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What is chlorella?

I've written that chlorella, as its name implies, is loaded with chlorophyll, the substance that makes plants green.13 It belongs to the green algae, and it lives and grows as single cells rather than as a seaweed.1

Each cell is wrapped in a tough wall made of cellulose, which your body can't digest, so most supplements break the cell walls open mechanically.1 That's what "broken cell wall" or "cracked cell wall" on a label refers to.

The trials on this page used C. vulgaris, C. pyrenoidosa and a close relative, Parachlorella beijerinckii, and a few used extracts made from the alga instead of the whole cells. Each study below names the form it tested.1415

A short history of chlorella

After C. vulgaris, scientists named a second species, C. pyrenoidosa, in 1903.1 Interest in chlorella as a human food began in the early 1950s, during a global food crisis, and it was first produced and eaten in Asia, mainly in Japan, before it spread worldwide as a supplement.1 That history is why so much of the human research on this page comes from Japan.

Chlorella nutrition facts

USDA FoodData Central lists no standard nutrient record for chlorella, only brand label entries, so these values come from laboratory analyses of commercial products: five chlorella powders tested in Germany in 2021 and the label values of 13 products gathered in a 2020 review.81 Products differ a lot, and in the German tests the measured values often didn't match the label.8

Protein measured with a nitrogen factor suited to algae; the standard factor used on many labels gives 53.0 to 61.4 grams per 100 grams.8

A daily serving's biggest contributions are chlorophyll, vitamin D2, folate and some iron, plus carotenoids your body absorbs. A single 6-gram dose of C. vulgaris carrying 7.08 milligrams of lutein raised blood lutein, beta-carotene and zeaxanthin in 11 healthy men,16 and in a placebo-controlled trial of 12 older adults, 8 grams a day for 2 months raised lutein in the blood and red blood cells.17

Does chlorella have vitamin B12?

Some chlorella does, in the active forms your body uses. In chlorella tablets tested in Japan, the B12 was mostly true vitamin B12, and four high- and moderate-B12 tablet types carried the coenzyme forms adenosylcobalamin (about 32%) and methylcobalamin (about 8%).1218 Methylcobalamin has also been identified in C. vulgaris itself.19

Your body can put it to work. In a study of 17 vegans and vegetarians with signs of low B12 and no comparison group, 9 grams of C. pyrenoidosa a day for 60 days lowered methylmalonic acid, a marker that rises when B12 runs low, by about 34%, and 15 of the 17 saw it drop at least 10%.20

The amount depends on the product. Across 19 chlorella supplements, B12 ranged from less than 0.1 to about 415 micrograms per 100 grams, a few high-B12 tablets carried inactive look-alike compounds, and all five powders tested in Germany came in below the lab's limit of measurement, 20 micrograms per 100 grams.128 If you're vegan or vegetarian, you almost always want to supplement with a B complex or a B12 supplement.21 Chlorella can add to that. Eggs and wild-caught fish are good everyday sources; see the top vitamin B12 foods.

Is chlorella a good source of protein and iron?

By weight, yes. In a randomized trial of 36 young adults, the 12 who drank 25 grams of protein from chlorella raised their muscle-building rates at rest and after a leg workout about as much as the groups given the same protein from spirulina or mycoprotein.22 At 3 to 5 grams a day, though, chlorella adds only a gram or two of protein, so build your meals around high-protein foods.

A 3-gram serving supplies about 0.6 to 1.6 milligrams of iron.8 A 2025 review of 32 studies of spirulina and C. vulgaris, 7 of them in people and the rest in animals, found better hemoglobin, ferritin and red blood cell counts,23 and the pregnancy section below covers a study that found less anemia on chlorella. Very large amounts change the picture, as the safety section explains. For food sources, see these iron-rich foods.

Chlorella vs. spirulina: what's the difference?

Chlorella and spirulina are different organisms that often share a jar: chlorella is a green microalga, and spirulina is a cyanobacterium, the group often called blue-green algae.22 I recommend both as gentle binders, at 3 to 5 grams a day.6

What is chlorella good for?

Top chlorella benefits

Binding heavy metals comes first here because that's the job chlorella does in my protocols. Then come cholesterol, fatty liver, immune markers, nutrition in pregnancy, blood sugar and blood pressure, and energy for exercise.

Can chlorella help your body clear heavy metals?

Your body does its own detox work. Real cellular detoxification happens deep in your liver, in a two-step process, with help from your gut, kidneys, lymph and skin, and a binder supports that work.6

The first step is lowering what comes in. My Mitochondrial Longevity Protocol starts there, with filtered water, glass instead of plastic and a clean-air bedroom,35 and our heavy metal detox guide covers the everyday sources of mercury, lead and arsenic and how to cut them.

Then come the binders. For an ongoing detox, which is what I prefer, gentle binders such as chlorella, pectin, and humic and fulvic acid are much better for long-term use than activated charcoal, which I keep to a week or two because it backs you up and binds a lot of your nutrients and minerals.9 I also recommend plenty of steamed vegetables along with spirulina, chlorella, probiotics and chlorophyll, which all help bind and eliminate heavy metals.36 Cilantro and chlorella make a strong pair, too: cilantro helps detoxify, and chlorella binds to toxins.37

The clearest human study comes from Japan. In a 3-month trial, 58 healthy adults chose whether to join the chlorella group or the control group. The 35 who took chlorella had 9 grams a day of Parachlorella beijerinckii tablets, 15 after each meal, the 23 controls took nothing, and fish intake held steady in both groups. Among the people with blood tests at both ends, blood mercury fell more in the 19 chlorella takers than in the 20 controls. Hair mercury fell within the chlorella group, though that drop wasn't significantly different from the controls'. The only side effect reported was green stools. The chlorella maker supplied the tablets, and its researchers ran the trial with Japan's National Institute for Minamata Disease.14 For the signs of too much mercury, see our guide to mercury poisoning.

Here's how the research fits together, step by step. The first three steps come from animal studies:

Timing keeps a binder on target. Binders trap everything indiscriminately, so in my protocols they go two hours away from food, herbs, supplements and medications.7 Our heavy metal detox guide covers testing and the other steps, including glutathione support.

Does chlorella lower cholesterol, blood sugar and blood pressure?

Cholesterol and triglycerides

The 2026 analysis drew its cholesterol results from 317 to 341 people, depending on the measure, and HDL rose 1.82 mg/dL, a change just short of significance.3 An earlier analysis of 19 randomized trials in 797 people found total cholesterol down 9.09 mg/dL and LDL down 8.32 mg/dL, with the clearest drops in trials that ran 8 weeks or longer at more than 4 grams a day; triglycerides and HDL didn't change significantly in that pool.25 A 2022 analysis of 10 trials of C. vulgaris in 539 adults found total cholesterol down 7.47 mg/dL and LDL down 7.71 mg/dL,40 while a 2025 pool of 12 chlorella studies found no significant change in blood fats.41

Two placebo-controlled trials from the same Korean university show what this looks like in a month. In 63 adults with mildly high cholesterol who finished the first, 5 grams of chlorella tablets a day for 4 weeks lowered triglycerides 10.3% while they rose 11.9% on placebo, and total cholesterol fell 1.6% against a 0.03% rise on placebo; neither the people nor the researchers knew who got what.32 Lutein and zeaxanthin in the blood rose 89.6% on chlorella, against a 1.7% drop on placebo.32

In the second trial, 34 healthy adults ate three eggs a day, about 510 milligrams of dietary cholesterol, for 4 weeks. LDL rose just 1.7% in the people taking 5 grams of chlorella a day, against 14.3% on placebo.42

Our guides to normal cholesterol levels and high triglycerides explain the numbers, and these cholesterol-lowering foods cover the food side.

Blood sugar and insulin

In the 2026 analysis, chlorella lowered fasting insulin by 0.86 µU/mL and HOMA-IR, a measure of how well your cells respond to insulin, by 0.22, while fasting blood sugar fell 1.62 mg/dL, a change that wasn't significant.3 The earlier analysis of 19 trials found fasting blood sugar down 4.23 mg/dL.25 In a placebo-controlled trial of 84 adults with type 2 diabetes, 1.5 grams of C. vulgaris a day for 8 weeks didn't change blood sugar, HbA1c or insulin, and the researchers suggested testing higher doses for longer.26 Food, movement and sleep do the heavy lifting for blood sugar; an insulin resistance diet is the place to start, and our guide to normal blood sugar explains what your numbers mean.

Blood pressure

Across 19 randomized trials, chlorella lowered systolic blood pressure by 4.51 mmHg and diastolic by 1.64 mmHg, and the drops showed up most clearly in people with high blood pressure and in trials of 8 weeks or longer at more than 4 grams a day.25 In the 2026 analysis of the general population, blood pressure didn't change significantly.3 In a 12-week placebo-controlled trial of 80 adults with high-normal or borderline high blood pressure, a GABA-rich chlorella supplement, carrying 20 mg of GABA per dose and taken twice a day, lowered systolic pressure compared with placebo, and the drop was bigger in the borderline group.27 My free High Blood Pressure protocol lays out the full plan, and these natural ways to lower blood pressure are a good start.

Weight

Chlorella gives weight a small nudge. In the 2026 analysis, people taking chlorella lost 1.28 kg, about 2.8 pounds, more than the control groups, and body fat fell 0.73 percentage points;3 in people with fatty liver, weight fell 1.62 kg, about 3.6 pounds.4 Treat it as a small extra on top of the food and activity changes that drive weight loss, covered in our guide to how to lose belly fat.

Can chlorella support a fatty liver?

Yes, as a support. A 2026 analysis pooled 7 trials, all in Iran, in 375 adults with non-alcoholic fatty liver who took 1,000 to 1,500 mg of C. vulgaris a day for 8 to 12 weeks. Chlorella lowered the liver enzymes AST by 4.99 U/L and ALP by 14.84 U/L, fasting blood sugar by 6.25 mg/dL, LDL by 6.45 mg/dL, hs-CRP in the 2 trials that measured it, and weight by 1.62 kg; ALT and triglycerides didn't change significantly.4

One of those trials shows the detail. In 70 adults with fatty liver confirmed by ultrasound, 55 of whom finished, four 300 mg tablets of C. vulgaris a day for 8 weeks brought more weight loss than placebo tablets, and fasting blood sugar and the inflammation marker TNF-α improved more than on placebo. Liver enzymes and hs-CRP fell only in the chlorella group, while insulin and the insulin-resistance score rose in that group; neither the people nor the researchers knew who got what.434 Our guide to liver function explains what those enzymes measure.

Does chlorella boost your immune system?

I've written that chlorella bolsters immunity,13 and a placebo-controlled trial in Korea tested it on immune markers in healthy adults. Of the 60 who started, 51 finished 8 weeks of 5 grams of chlorella tablets a day (28 people) or a placebo (23); neither the people nor the researchers knew who got what. Natural killer cell activity rose significantly on chlorella, and the rise was significantly bigger than on placebo. The immune messengers interferon-gamma and interleukin-1β rose too.5 Natural killer cells are front-line immune cells that respond to viruses and tumor cells.1

An extract made from chlorella was tested with the flu vaccine. In 117 adults 50 and older who finished a 28-day placebo-controlled trial, the extract didn't raise the vaccine antibody response overall, though adults aged 50 to 55 on the higher 400 mg dose made more antibodies against two of the three strains.15

Two more trials point the same way for secretory IgA, an antibody in saliva that's part of your first line of defense. In 15 men who each tried a chlorella-based supplement and a placebo for 4 weeks, secretory IgA rose after chlorella, and in 10 female kendo athletes who each tried both, it held up through a hard training camp on chlorella while it fell on placebo.4445 The same immune-raising effect is why the safety section asks people on immune-suppressing medicine to check first. For the bigger picture, see how to boost your immune system.

What do the chlorella pregnancy studies show?

A Japanese hospital team led most of this research. In their largest study, 70 pregnant women were placed in a chlorella group (32) or a control group (38), and the chlorella group took 6 grams a day from weeks 12 to 18 of pregnancy until delivery. Fewer women in the chlorella group were anemic, with hemoglobin below 11 g/dL, in the second and third trimesters, and proteinuria and edema, two signs of pregnancy-induced high blood pressure, were less common in the third trimester.10 Our pregnancy diet guide covers the foods that matter most in those months.

The same team measured dioxins, environmental pollutants that pass from mother to baby through the placenta and breast milk.11 In 44 pregnant women, the 23 who were told to take chlorella tablets during pregnancy had about 30% lower total dioxin levels in their breast milk than the controls.11 In a second group of 35 women, the 18 who took chlorella had lower dioxin levels in their breast milk, along with higher levels of IgA, an antibody that helps protect nursing babies from infection.46

Two newer studies add to the picture. In 20 healthy pregnant women, the 10 who took 6 grams a day from weeks 16 to 20 until delivery had 2.6 times more lutein, 2.7 times more zeaxanthin and 1.7 times more beta-carotene, a source of vitamin A, in their early breast milk.47 And in 22 pregnant women with low-grade inflammation, enrolled at 16 weeks and placed in a group by the month of their clinic visit, with everyone knowing which group they were in, none of the 10 taking 6 grams of chlorella a day had constipation after the intervention, against 8 of the 12 controls; before it, 6 of 10 and 5 of 12 had been constipated. Newborn weights were similar.48

None of these studies assigned women at random, and in each study a chlorella maker supplied the tablets or had researchers on the team.10114847 The findings point the same way: less anemia, fewer signs of pregnancy-induced high blood pressure and cleaner breast milk.

Can chlorella give you more energy?

For exercise, the trials found lower blood lactate and more sprint power. In 14 trained male cyclists who each tried chlorella and a placebo, 6 grams a day for 21 days lowered blood lactate and heart rate during a 1-hour ride and raised sprint power: average sprint power was 9.5 watts per kilogram on chlorella against 9.0 on placebo, and peak power 12.0 against 11.4. Hemoglobin was 149.1 g/L on chlorella against 143.4 on placebo, and the time trial and lactate threshold didn't change.28 Even 2 days helped in 20 young adults who each tried both: blood lactate during moderate cycling was 2.67 mmol/L on chlorella, against 3.05 on placebo.29

A 2026 analysis of 22 randomized trials of algae supplements in 822 people found longer time to exhaustion and less muscle damage, with larger effects in the chlorella trials.30 And in a placebo-controlled trial of 27 healthy men, 6 grams a day for 4 weeks raised antioxidant capacity at rest, and their fatigue scores didn't climb after exercise during the chlorella period, as they did at every other point in the study.49

Chlorella for women, cancer support and other uses

Chlorella benefits for women

Chlorella eased painful periods in a placebo-controlled trial. In 44 young women with primary dysmenorrhea, 1,500 mg of chlorella a day in soft gels for 8 weeks reduced the severity and duration of menstrual pain compared with placebo and lowered prostaglandins, the compounds behind cramping, along with hs-CRP; fatigue, headache and nausea eased too.31 For more relief, see how to get rid of period cramps. Chlorella's iron and folate matter for women as well, and the pregnancy studies above cover anemia.

Can chlorella help during cancer treatment?

For anyone facing cancer, I put diet, exercise, prayer, vitamin D, high-dose vitamin C and hyperthermia first, and chlorella can be one supportive piece of that plan. In lab studies, chlorella extracts slowed the growth of human liver and colon cancer cells, and in mice with tumors, chlorella helped the immune response.1 In people, the evidence is one early study with no comparison group: 21 people with glioma, a brain tumor (15 of them glioblastoma), added chlorella to their diet and had monthly checkups over the 2-year study. Their immune measures stayed near normal while they had chemotherapy or took steroids, and the researchers observed fewer respiratory infections and flu-like illnesses.50 If you're in cancer treatment, clear chlorella with your oncology team first. My free Cancer Support Protocol lays out the root-cause plan.

Other early research

In 92 adults with major depression who were already taking antidepressants, 1,800 mg a day of a chlorella extract added to their usual care for 6 weeks lowered depression and anxiety scores more than usual care alone, though mood-related symptoms improved more in the usual-care group; people knew which treatment they got.51 Our guide to natural remedies for depression covers more. In a pilot study of 20 adults with fibromyalgia and no comparison group, 7 of the 18 who finished 2 months of 10 grams of chlorella tablets plus a chlorella extract a day felt better, 6 felt no change and 5 felt worse, and as a group their tender-point pain index fell 22%, from 32 to 25.52

How much chlorella should you take a day?

These are the amounts used in the human trials, by goal:

As a binder in my parasite protocol, chlorella goes in during the bind phase at 1 to 3 grams a day, taken in the afternoon.7 My candida protocol pairs 2 to 3 grams of chlorella with 5 grams of modified citrus pectin a day, as light binders that catch toxins before they're reabsorbed, two hours from food and supplements.24

Tablet sizes vary, so check the milligrams on your label. In the Japanese pregnancy trial, 30 tablets made 6 grams, about 200 mg each,48 so at that size, 3 to 5 grams is 15 to 25 tablets.

Start with about 1 gram a day and build up to your full amount over a week or two. Digestive changes are most common in the first couple of weeks and tend to settle, as the safety section explains.54 Binders are dehydrating, so drink more water while you take them.7

How to take chlorella: powder, tablets and timing

With gentle, natural binders like chlorella, I'd take them first thing in the morning, between meals or right before bed, and some can even go with a meal.37 When binding heavy metals is the goal, though, take chlorella on its own, two hours from food, supplements and medications.7 When you're using it as a green food, a scoop in your breakfast smoothie is fine.

I recommend a daily superfood powder as an insurance policy, since many of us aren't getting enough berries and vegetables, and chlorella is one of the greens that fits that role, alongside vegetables rather than in place of them.55 Our guide to superfoods covers others.

How to choose a quality chlorella

Chlorella takes up what's in the water it grows in, so the product you buy matters.56 In a 2025 test of 52 spirulina and chlorella products, every one met EU limits for toxic metals, but at the label dose three chlorella powders supplied 17% to 29% of the tolerable weekly intake of aluminum, and researchers found pharmaceutical residues, most often caffeine, along with drugs such as metronidazole and carbamazepine. Organic products didn't differ significantly from conventional ones.56 The five chlorella powders tested in Germany also stayed under EU limits for arsenic, cadmium, mercury and lead.8 And in a 2022 review of 10 chlorella trials, only 2 had checked their own product's chlorella content, purity and contamination.40

Check the label for these:

• Third-party testing for heavy metals and contaminants, with a lab report you can see; an organic seal alone isn't proof56

• The species on the label, such as Chlorella vulgaris or C. pyrenoidosa, the forms in most supplements12

• Broken or cracked cell walls, since your body can't digest the intact cellulose wall1

• Grams per serving, so you can reach 3 to 5 grams a day6

• Measured B12, vitamin K and iron values, since lab results and label values can differ812

Chlorella side effects and who should skip it

In a 12-week study of 18 adults with chronic hepatitis C and no comparison group, who took 3 grams of chlorella tablets a day for a week, then 4.5 grams, plus a liquid chlorella extract from the first day, 4 of the 13 who finished felt their existing constipation get worse in the first 2 weeks, and 2 had mild diarrhea in the first week; both settled after that.54 In the 3-month mercury trial, green stools were the only side effect at 9 grams a day.14 In the flu-vaccine trial of a chlorella extract, side effects matched placebo except fatigue, reported by 44% on the 200 mg dose against 19% on placebo.15

Very large amounts carry trade-offs. In a 14-day randomized trial of 80 healthy adults, the group that drank a smoothie with 15 grams of chlorella a day saw their cholesterol fall, but their iron, ferritin, transferrin saturation and selenium fell too, and uric acid rose in their blood and urine.53 That's three to five times my daily amount, one more reason to stay at 3 to 5 grams.

A few rare, serious reactions have been reported, each in a single case report:

• Anaphylaxis, with very low blood pressure, wheezing, hives and diarrhea, in a 75-year-old man after C. vulgaris supplements.58
• Asthma in a pharmacist who handled a chlorella preparation at work.59
• Kidney inflammation, called acute tubulointerstitial nephritis, in a boy after 3 months of chlorella tablets; his kidney function improved after he stopped them and was treated.60

Allergy to chlorella has also been documented in children.61 Stop chlorella and call 911 or go to an emergency room if you get hives, wheezing, trouble breathing or feel faint after taking it.

If you take a prescription, don't stop it or change the dose on your own; any change goes through the doctor who prescribed it. Our guide to vitamin K foods lists the others to keep steady if you take warfarin.

The bottom line

Chlorella: frequently asked questions

References

1. Bito T, Okumura E, Fujishima M, et al. Potential of Chlorella as a Dietary Supplement to Promote Human Health. Nutrients. 2020;12(9):2524. doi:10.3390/nu12092524
2. Axe J. Cellular Health EXPERT: How to Build Bulletproof Cells for Energy, Detox & Longevity. The Dr. Josh Axe Show. 2025 (activated charcoal only for short-term serious detox, at 42:39; chlorella and pectin among the binders he likes best, at 42:54; YouTube: https://www.youtube.com/watch?v=PnGsVH3_nqY).
3. Mardani H, Karimi MA, Sharifi M, et al. Beneficial effects of Chlorella species supplementation in the general population: a GRADE-assessed systematic review and dose-response meta-analysis. Nutr Diabetes. 2026;16(1):44. doi:10.1038/s41387-026-00449-3
4. Jafari A, Mardani H, Nezhad BP, et al. The beneficial effects of Chlorella vulgaris supplementation on health-related indices in patients with non-alcoholic fatty liver disease: a GRADE-assessed systematic review and meta-analysis. BMC Cardiovasc Disord. 2026;26(1):221. doi:10.1186/s12872-025-05433-w
5. Kwak JH, Baek SH, Woo Y, et al. Beneficial immunostimulatory effect of short-term Chlorella supplementation: enhancement of natural killer cell activity and early inflammatory response (randomized, double-blinded, placebo-controlled trial). Nutr J. 2012;11:53. doi:10.1186/1475-2891-11-53
6. Axe J, Cole W. Heal Your Cells. Avery; 2026. ISBN 9798217181353 (real cellular detoxification in the liver's two-step process; "Precision Healing Protocols," liver supplement list, item 6 "Spirulina/chlorella": binds heavy metals, supports detox, 3–5 g/day powder or capsules, p. 344).
7. Axe J. Heal From Parasites Protocol: The 30-Day System. DrAxe.com. 2026 (Phase 4, Bind and eliminate: binders 2 hours away from food, herbs and supplements; chlorella in the afternoon, 1–3 g daily; pregnancy and breastfeeding on the avoid list).
8. Sandgruber F, Gielsdorf A, Baur AC, et al. Variability in Macro- and Micronutrients of 15 Commercially Available Microalgae Powders. Mar Drugs. 2021;19(6):310. doi:10.3390/md19060310
9. Axe J. Cellular Toxicity: The Root Cause of Aging, Inflammation & Chronic Disease. The Dr. Josh Axe Show. 2026 (charcoal short-term at 33:48; ongoing detox with gentle binders such as spirulina and chlorella at 33:59; YouTube: https://www.youtube.com/watch?v=yNwVs_gAjBc).
10. Nakano S, Takekoshi H, Nakano M. Chlorella pyrenoidosa supplementation reduces the risk of anemia, proteinuria and edema in pregnant women. Plant Foods Hum Nutr. 2010;65(1):25-30. doi:10.1007/s11130-009-0145-9
11. Nakano S, Noguchi T, Takekoshi H, et al. Maternal-fetal distribution and transfer of dioxins in pregnant women in Japan, and attempts to reduce maternal transfer with Chlorella (Chlorella pyrenoidosa) supplements. Chemosphere. 2005;61(9):1244-55. doi:10.1016/j.chemosphere.2005.03.080
12. Bito T, Bito M, Asai Y, et al. Characterization and Quantitation of Vitamin B12 Compounds in Various Chlorella Supplements. J Agric Food Chem. 2016;64(45):8516-8524. doi:10.1021/acs.jafc.6b03550
13. Axe J. Ancient Remedies: Secrets to Healing with Herbs, Essential Oils, CBD, and the Most Powerful Natural Medicine in History. Little, Brown Spark (Hachette Book Group); 2021 (Chapter 5, "Meals Are Medicine," green foods passage: chlorella "loaded with chlorophyll," decreasing heavy-metal absorption and bolstering immunity).
14. Maruyama I, Uchikawa T, Kanno T, et al. Chlorella supplementation decreases methylmercury concentrations of hair and blood in healthy volunteers. Fundam Toxicol Sci. 2018;5(3):117-122. doi:10.2131/fts.5.117
15. Halperin SA, Smith B, Nolan C, et al. Safety and immunoenhancing effect of a Chlorella-derived dietary supplement in healthy adults undergoing influenza vaccination: randomized, double-blind, placebo-controlled trial. CMAJ. 2003;169(2):111-7.
16. Serra AT, Silva SD, Pleno de Gouveia L, et al. A Single Dose of Marine Chlorella vulgaris Increases Plasma Concentrations of Lutein, β-Carotene and Zeaxanthin in Healthy Male Volunteers. Antioxidants (Basel). 2021;10(8):1164. doi:10.3390/antiox10081164
17. Miyazawa T, Nakagawa K, Takekoshi H, et al. Ingestion of Chlorella reduced the oxidation of erythrocyte membrane lipids in senior Japanese subjects. J Oleo Sci. 2013;62(11):873-81. doi:10.5650/jos.62.873
18. Kittaka-Katsura H, Fujita T, Watanabe F, et al. Purification and characterization of a corrinoid compound from Chlorella tablets as an algal health food. J Agric Food Chem. 2002;50(17):4994-7. doi:10.1021/jf020345w
19. Kumudha A, Selvakumar S, Dilshad P, et al. Methylcobalamin--a form of vitamin B12 identified and characterised in Chlorella vulgaris. Food Chem. 2015;170:316-20. doi:10.1016/j.foodchem.2014.08.035
20. Merchant RE, Phillips TW, Udani J. Nutritional Supplementation with Chlorella pyrenoidosa Lowers Serum Methylmalonic Acid in Vegans and Vegetarians with a Suspected Vitamin B₁₂ Deficiency. J Med Food. 2015;18(12):1357-62. doi:10.1089/jmf.2015.0056
21. Axe J. 10 Signs You Have a B Vitamins Deficiency (How to Boost B Vitamins Naturally). The Dr. Josh Axe Show. 2024 (vegans and vegetarians supplement a B complex or B12; YouTube: https://www.youtube.com/watch?v=PpssCzYFqDY).
22. van der Heijden I, West S, Monteyne AJ, et al. Algae Ingestion Increases Resting and Exercised Myofibrillar Protein Synthesis Rates to a Similar Extent as Mycoprotein in Young Adults. J Nutr. 2023;153(12):3406-3417. doi:10.1016/j.tjnut.2023.08.035
23. Lacurezeanu A, Vodnar DC. Arthrospira platensis and Chlorella vulgaris Consumption on Iron Status: A Systematic Review of In Vivo Studies. Mol Nutr Food Res. 2025;69(24):e70318. doi:10.1002/mnfr.70318
24. Axe J. The Candida Cleanse Protocol: The 30-Day Healing Protocol. DrAxe.com. 2026 (p. 21, Supplements: chlorella plus modified citrus pectin, 2–3 g plus 5 g daily, two hours from food and supplements).
25. Fallah AA, Sarmast E, Habibian Dehkordi S, et al. Effect of Chlorella supplementation on cardiovascular risk factors: A meta-analysis of randomized controlled trials. Clin Nutr. 2018;37(6 Pt A):1892-1901. doi:10.1016/j.clnu.2017.09.019
26. Hosseini AM, Keshavarz SA, Nasli-Esfahani E, et al. The effects of Chlorella supplementation on glycemic control, lipid profile and anthropometric measures on patients with type 2 diabetes mellitus. Eur J Nutr. 2021;60(6):3131-3141. doi:10.1007/s00394-021-02492-5
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Dr. Josh Axe, DC, DNM, CNS

Doctor of Natural Medicine · Founder, DrAxe.com

Dr. Axe is a certified doctor of natural medicine, clinical nutritionist, and multiple New York Times bestselling author. He has spent 20+ years in clinical practice helping people heal at the root cause and founded one of the most-visited natural-health platforms in the world.

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