What Is Jellyfish Protein (Apoaequorin)?

Used for boosting memory, science to back its use for dementia isn't there

Alternative practitioners have long asserted that 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.

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

In recent years, apoaequorin has been used to produce the dietary supplement Prevagen, which its manufacturer claims can improve memory, mental function, and sleep quality.

Glowing blue jellyfish against a black background
boryak / Getty Images

Apoaequorin was first isolated from the crystal jellyfish (Aequorea victoria) in 1962. In nature, apoaequorin produces a blue light when exposed to calcium.

What Is Jellyfish Protein Used For?

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 like calretinin and parvalbumin, some scientists contend that it can improve calcium regulation and prevent—or even reverse—the calcification of brain tissue.

By doing so, apoaequorin can theoretically treat or prevent:

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

Of the currently available research, which we explore here, 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

One such example is the Madison Memory Study, 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, while the other half received a placebo. All participants completed computerized cognitive tests several times throughout the 90-day trial.

Compared to the group receiving the placebo, those provided the apoaequorin supplement exhibited 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 that the apoaequorin supplement was effective in "addressing declines in cognitive function associated with aging."

Despite the positive findings, the study was marred by the highly subjective way in which participants were selected. In the end, self-reported "memory problems" may be caused by any number of things, particularly in people with such vast age differences.

Improvements were seen only in healthy or mildly impaired adults; no improvements were seen in those with significant cognitive impairment.

Moreover, the fact that participants were regularly tested throughout the study would invariably result in cognitive improvements. Even in people with early Alzheimer's, routine brain exercises (a.k.a. cognitive training) will almost invariably improve memory and cognitive function, as would increased social interaction.

Without a cohesive factor to justify the selection (such as a diagnosis of early-stage Alzheimer's) and other confounding factors, any conclusions drawn could be misleading or easily misconstrued.

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.

Certainly with Alzheimer's or any other form of dementia, a brain scan—using computed tomography (CT) or magnetic resonance imaging (MRI)—would provide far better insights into the effects of the apoaequorin on the brain given the suggested mechanism of action. To date, there has been a glaring absence of such research.

The controversy surrounding jellyfish protein reached an apex in 2019 when the manufacturers of Prevagen, a memory-boosting supplement made of synthetic apoaequorin, were hit with a second lawsuit by the U.S. Federal Trade Commission (FTC) for misleading advertising.

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 stated that the improvements were not statistically relevant.

Possible Side Effects

Little is known about the long-term safety of apoaequorin in any form. Studies utilizing synthetic apoaequorin have suggested that 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 pregnant women or nursing babies. If you are pregnant or breastfeeding, it is best to avoid this supplement.

It is also 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 chronic medications or are managing a chronic condition like diabetes or high blood pressure.

Dosage and Preparation

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 are no prescription versions 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.

Other 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).

Are there other manufacturers that use apoaequorin in their memory-boosting products?
Prevagen is the only major brand that uses apoaequorin as its active ingredient. There are other supplements that claim to enhance brain performance, each with different active ingredients.

What other supplements are used to improve brain performance?
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.

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.

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9 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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