What Is Jellyfish Protein (Apoaequorin)?

Used in the supplement Prevagen and claimed to boost memory

Jellyfish protein (apoaequorin) is a recombinant protein originally extracted from the Aequorea victoria species of jellyfish. In nature, apoaequorin produces a blue light when exposed to calcium. Today it is produced in a lab by a company called Quincy Bioscience. It is the primary ingredient in the dietary supplement Prevagen.

Alternative practitioners say jellyfish protein (apoaequorin) taken by mouth can bind to calcium in the brain and improve the electrical signals between nerve cells. This is believed to improve memory while slowing the progressive loss of cognitive function.

It is thought that calcium deposits in the brain can contribute to dementia and Alzheimer's disease. This is why jellyfish protein has been suggested as a possible prevention strategy and treatment.

This article will discuss jellyfish protein, its purported benefits, and what the science says about its effectiveness. It also takes a look at side effects, precautions, and what to look for when buying jellyfish protein.

Glowing blue jellyfish against a black background
boryak / Getty Images

Dietary supplements are not regulated like drugs in the United States, meaning the Food and Drug Administration (FDA) does not approve them for safety and effectiveness before products are marketed. When possible, choose a supplement that has been tested by a trusted third party, such as USP, ConsumerLabs, or NSF. However, even if supplements are third-party tested, that doesn’t mean that they are necessarily safe for all or effective in general. It is important to talk to your healthcare provider about any supplements you plan to take and to check in about any potential interactions with other supplements or medications.

Supplement Facts

  • Active ingredient: Apoaequorin
  • Alternate names: Prevagen, Bioluminescence, Protéine-Liant-le Calcium
  • Legal status: Sold over the counter
  • Suggested dose: 10 mg, 20 mg, 50 mg
  • Safety considerations: May be safe for up to 90 days. There is no good data regarding its long-term safety. Do not take if you are pregnant or nursing.

Uses of Jellyfish Protein

Supplement use should be individualized and vetted by a healthcare professional, such as a registered dietitian, pharmacist, or doctor. No supplement is intended to treat, cure, or prevent disease.

Problems with calcium regulation are believed to play a key role in aging-related mental decline.

Because apoaequorin has a similar structure to calcium-binding proteins, some scientists think it can improve calcium regulation and prevent or reverse the calcification of brain tissue.

If true, apoaequorin could theoretically treat or prevent:

Despite health claims, there remains little evidence that jellyfish protein or apoaequorin supplements can treat any condition.

Of the currently available research, conclusions are often limited by the small size and/or poor design of the studies. Others are based largely on pseudoscience.

Memory and Verbal Learning

The Madison Memory Study was published in 2016 in the journal Advances in Mind-Body Medicine. It evaluated the effects of apoaequorin in 218 adults, ages 40 to 91, with self-reported memory problems.

Half were given a daily 10 milligram (mg) dose of an apoaequorin supplement. The other half received a placebo. All participants completed cognitive tests several times during the 90-day trial.

Subjects in the apoaequorin group had improvements in recall and verbal learning with each subsequent test. Those in the placebo group showed no significant improvements.

Based on the findings, the researchers concluded the apoaequorin supplement was effective in "addressing declines in cognitive function associated with aging."

Despite this, the study was flawed because of the way its participants were selected. For example, the ages of participants varied by as much as 50 years. Self-reported "memory problems" is also a vague criterion. Memory problems can be caused by any number of things, not just dementia.

Since participants weren't selected based on a common factor, such as an early-stage Alzheimer's diagnosis, the study's conclusions could be misleading or easily misconstrued.

Additionally, improvements were seen only in healthy or mildly impaired adults. No improvements were seen in those with significant cognitive impairment.

The way participants were tested is also problematic. Cognitive improvements are expected when repeating tests. Even in people with early Alzheimer's, routine brain exercises will almost always improve memory and cognitive function.

Of note, this study was funded by Prevagen manufacturer Quincy Bioscience.

Conclusions and Controversy

Shortcomings like these have enabled manufacturers to make claims that far exceed what the research actually reveals.

With Alzheimer's or any other form of dementia, a brain scan such as computed tomography (CT) or magnetic resonance imaging (MRI) would be the best way to evaluate the effects of apoaequorin. To date, there has been no such research.

In 2019, the U.S. Federal Trade Commission (FTC) sued the manufacturers of Prevagen for misleading advertising. This was the second such lawsuit.

In their lawsuit, the FTC accused Quincy Bioscience of making "false claims" that Prevagen can improve memory "within 90 days." The FTC pointed to the Madison Memory Study in which even the researchers said the improvements were not statistically relevant.

What Are the Side Effects of Jellyfish Protein?

Little is known about the long-term safety of apoaequorin in any form. Studies utilizing synthetic apoaequorin have suggested it is safe and well-tolerated for up to 90 days.

Common side effects include:

  • Headache
  • Dizziness
  • Nausea


There is not enough research assessing the safety of apoaequorin in those who are pregnant or nursing. If you are pregnant or breastfeeding, it is best to avoid this supplement.

Dosage: How Much Jellyfish Protein Should I Take?

Always speak with a healthcare provider before taking a supplement to ensure that the supplement and dosage are appropriate for your individual needs. 

Apoaequorin is found almost exclusively in the United States in the oral supplement Prevagen but is also used as an ingredient in other "memory-boosting" products. Natural apoaequorin derived from crystal jellyfish is not commercially available.

Prevagen is available over the counter as an oral or chewable tablet in 10 mg (regular-strength), 20 mg (extra-strength), and 50 mg ("professional-strength") formulations. Despite the use of the term "professional-strength," there is no prescription version of Prevagen.

Prevagen is taken once daily in the morning with or without food.

All listed dosages are according to the manufacturer. This information should not be construed to mean that the doses are either safe or effective.

What Happens If I Take Too Much Jellyfish Protein?

The health consequences of taking too much apoaequorin are unknown. Always follow the manufacturer's dosage recommendations.


It is unclear if apoaequorin can cause drug interactions. Speak with your healthcare provider if you are using or intend to use any complementary or alternative medicine. This is especially true if you are taking medications long-term or are managing a chronic condition like diabetes or high blood pressure.

It is essential to carefully read the ingredient list and nutrition facts panel of a supplement to know which ingredients and how much of each ingredient is included. Please review this supplement label with your healthcare provider to discuss any potential interactions with foods, other supplements, and medications.

How to Store Jellyfish Protein

Keep Prevagen in a cool, dry place in its original packaging.

Similar Supplements

Other supplements are sometimes recommended for similar purposes.

Although evidence of their memory and cognitive function benefits is limited, alternative practitioners often recommend aniracetam, gingko biloba, pregnenolone, and tyrosine. These are readily available online or at specialty nutritional stores.

Frequently Asked Questions

  • Can I take Prevagen if I have a seafood allergy?

    According to the manufacturer, Prevagen is non-allergenic. The claim is backed up by research funded by the manufacturer.

  • Is Prevagen covered by insurance?

    No, but most nutritional supplements aren't either. On the other hand, prescription drugs used to treat Alzheimer's disease will usually be covered, at least in part, by insurance. These include drugs like Aricept (donepezil), Exelon (rivastigmine), and Razadyne (galantamine).

Sources of Jellyfish Protein & What To Look For

Apoaequorin is the active ingredient in Prevagen. According to the manufacturer, Prevagen meets NSF standards. NSF is a third-party certification organization that performs quality testing on supplements like Prevagen.

Keep in mind that NSF certification is not a guarantee of safety or effectiveness. It is only an assurance that the product contains the ingredients listed on the label and that it is free from harmful levels of contaminants.


Jellyfish protein (apoaequorin) is a supplement ingredient claimed to improve memory and cognition. The scientific research supporting this claim, however, comes primarily from a small, poorly designed study financed by the manufacturer.

Apoaequorin is probably safe to take in recommended doses for up to 90 days. However, its long-term safety has not been established, and there are uncertainties about whether it is effective.

A Word From Verywell

If you are experiencing significant memory loss, avoid self-treating your condition. Rather, see your healthcare provider, who can perform tests or refer you to a neurologist for further evaluation to pinpoint the cause.

If you plan to try a supplement to improve your memory, speak to your healthcare provider about it first.

10 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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  2. Alzheimer's Drug Discovery Foundation. Apoaequorin.

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  6. United States Court of Appeals for the Second Circuit. Summary Order: FTC v. Quincy Bioscience Holding Co. New York City, New York: February 21, 2019.

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  8. Lee H, Birks JS. Ginkgo biloba for cognitive improvement in healthy individuals. Cochrane Database Syst Rev. 2018 Aug;2018(8):CD004671. doi:10.1002/14651858.CD004671.pub2

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By Tom Iarocci, MD
Tom Iarocci, MD, is a medical writer with clinical and research experience in hematology and oncology.