Scientists are studying a natural compound called PQQ that’s found in soil and certain foods. Early research suggests PQQ might protect our brains by reducing inflammation and stress at the cellular level, and it could help our brain’s energy-producing structures work better. This review looks at how PQQ works in the body and explores whether it could become a new treatment for brain disorders, including a rare condition called cerebral folate deficiency that affects children’s development. While the research is promising, most studies so far have been done in labs and on animals, so we need more human testing before doctors can recommend it as a treatment.

The Quick Take

  • What they studied: Whether a natural compound called PQQ (pyrroloquinoline quinone) can protect the brain and help treat brain diseases
  • Who participated: This is a review article that analyzed existing research studies—not a new experiment with human participants. The authors looked at laboratory studies and animal research about PQQ
  • Key finding: PQQ appears to protect brain cells by reducing harmful inflammation and oxidative stress (cellular damage), and it may improve how our brain’s energy factories (mitochondria) work. These effects were seen in laboratory and animal studies
  • What it means for you: PQQ shows promise as a potential future treatment for brain disorders, but it’s still in early research stages. Don’t expect it to be available as a medical treatment yet. More human studies are needed before doctors can recommend it

The Research Details

This is a review article, which means scientists read and summarized all the existing research about PQQ and its effects on the brain. They didn’t conduct a new experiment themselves. Instead, they gathered information from laboratory studies (where scientists test compounds in dishes and test tubes) and animal studies (where researchers tested PQQ on mice and other animals) to understand how this compound works.

The researchers focused on understanding PQQ’s chemical properties—basically, what it is and how it behaves in the body. They also looked at the different ways PQQ might protect brain cells, including how it reduces inflammation (swelling and irritation in the brain) and oxidative stress (a type of cellular damage). They examined research showing that PQQ helps brain cells produce energy more efficiently.

The authors also discussed a specific brain condition called cerebral folate deficiency, which is a rare disorder in children where important nutrients don’t reach the brain properly, causing developmental problems and seizures. They explored whether PQQ might help treat this condition.

Review articles are important because they help scientists and doctors understand what we know so far about a topic. By gathering all the existing research in one place, reviewers can identify patterns, spot gaps in our knowledge, and suggest what research should happen next. This type of article helps the scientific community decide whether a compound like PQQ is worth studying further in human trials

This is a review article published in a respected scientific journal, which means it went through quality checks. However, because it summarizes other people’s research rather than conducting new experiments, it depends on the quality of the studies it reviews. Most of the research discussed was done in laboratories and on animals, not humans. This is an important limitation—what works in a test tube or in mice doesn’t always work the same way in people. The article is useful for understanding the current state of knowledge, but it’s not proof that PQQ will work as a treatment in humans

What the Results Show

Research shows that PQQ appears to work as an antioxidant, which means it can neutralize harmful molecules in brain cells that cause damage. Think of it like a cleanup crew that removes trash from your cells. The studies reviewed found that PQQ can reduce inflammation in the brain, which is important because inflammation is linked to many brain disorders.

Animal studies demonstrated that PQQ helps improve how mitochondria function. Mitochondria are like tiny power plants inside our cells that produce energy. When these power plants work better, brain cells have more energy to do their jobs properly. This is significant because many brain disorders involve mitochondria that aren’t working well.

The research also suggests that PQQ activates several protective pathways in brain cells—basically, it turns on the brain’s natural defense systems. These defense systems help protect brain cells from damage and death. In laboratory studies, PQQ showed promise in models of brain injury and various neurological diseases.

Additionally, animal studies showed that not getting enough PQQ in the diet can cause problems with growth and reproduction, suggesting that PQQ is important for normal body function.

The review highlighted that PQQ is naturally found in foods and soil, which means it’s not a completely artificial compound—it’s something our bodies may have evolved to use. The research suggests PQQ may play a role in normal growth and development, not just in treating disease. The authors noted that PQQ’s multiple protective mechanisms (reducing inflammation, improving energy production, and activating defense systems) make it an interesting compound because it works in several different ways at once, which could make it more effective than treatments that only work one way

This review builds on growing interest in PQQ over the past several years. Earlier research identified PQQ as important for bacteria, but more recent studies have shown it may be important for mammals (including humans) too. The focus on PQQ’s brain-protective effects is relatively new compared to research on other antioxidants. The emerging interest in PQQ for cerebral folate deficiency represents a newer application that hasn’t been extensively studied yet. Overall, this review suggests PQQ deserves more attention from researchers studying brain disorders

The biggest limitation is that most research reviewed was conducted in laboratories or on animals, not in humans. What works in a test tube or in mice may not work the same way in people. There are very few human studies on PQQ’s effects on brain health. The review doesn’t provide information about how much PQQ people would need to take or whether it’s safe at different doses in humans. We don’t know if PQQ from food sources is enough to provide brain protection, or if supplements would be needed. The research on cerebral folate deficiency specifically is still very early. Additionally, this is a review of existing research, not a new study, so it can’t provide new evidence—it can only summarize what’s already been published

The Bottom Line

Based on current evidence (which is still limited), there is no strong recommendation to take PQQ supplements for brain health at this time. The research is promising but not yet conclusive. If you’re interested in supporting brain health, focus on proven strategies: eat a balanced diet with plenty of fruits and vegetables (which contain PQQ naturally), exercise regularly, get enough sleep, and manage stress. If you have a specific neurological condition, talk to your doctor before taking any supplements. For cerebral folate deficiency specifically, this is a rare condition that requires medical supervision—don’t attempt to self-treat with PQQ

Researchers studying brain disorders and neurological diseases should pay attention to this review because it suggests PQQ is worth investigating further. Parents of children with cerebral folate deficiency might find this interesting, but they should discuss it with their child’s neurologist before considering any treatment changes. People interested in brain health and nutrition may find this information valuable for understanding emerging research. People with neurodegenerative diseases (like Parkinson’s or Alzheimer’s) might be interested, but again, don’t make changes without talking to your doctor. People who are generally healthy probably don’t need to worry about PQQ right now

If PQQ does eventually become a medical treatment, it will likely take several more years of research. First, scientists need to conduct human studies to see if it’s safe and effective. Then, if results are promising, it would need to go through the approval process with regulatory agencies like the FDA. This process typically takes years. Even if PQQ becomes available as a supplement or treatment, benefits wouldn’t be immediate—it would likely take weeks or months of consistent use to see any effects, similar to other brain-health interventions

Want to Apply This Research?

  • Track dietary sources of PQQ by logging foods known to contain it (like kiwi fruit, papaya, green tea, and fermented foods) and note any changes in energy levels, mood, or cognitive clarity over 8-12 weeks. Use a simple 1-10 scale for subjective measures
  • Start incorporating PQQ-rich foods into your diet naturally: add kiwi to breakfast, drink green tea, include fermented foods like natto or tempeh, and eat more whole grains. This provides PQQ from food sources while you wait for more research on supplements
  • Create a long-term wellness log tracking overall brain health markers: sleep quality, energy levels, mood stability, and cognitive function. Monitor these weekly and review trends monthly to see if dietary changes correlate with improvements. Share results with your healthcare provider if you notice significant changes

This article summarizes scientific research about PQQ but is not medical advice. PQQ is not currently approved by the FDA as a treatment for any disease. Do not start taking PQQ supplements or change your treatment plan based on this information without consulting your doctor first. This is especially important if you have a neurological condition, are pregnant, breastfeeding, or taking medications. Most research on PQQ has been conducted in laboratories and on animals, not humans, so we don’t yet know if it’s safe or effective for treating brain disorders in people. Always talk to a healthcare provider before starting any new supplement or treatment