The Proven Decision Tree For A Supplier Change Notice
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A buyer-side decision tree for handling an intermediate supplier change notice — what to accept, contest, or reject, and how to log the call.
Which Foods Contain PQQ in Daily Life?
What is PQQ?
PQQ is an excellent nutrient that can help maintain nerve health, slow aging, improve sleep, provide antioxidant benefits, and enhance beauty. To maintain good health and boost immunity, people can increase their PQQ supply through various means.
The key is to balance food choices, increase exercise, maintain a positive attitude, and manage sleep and rest schedules. While obtaining PQQ, it’s also crucial to maintain overall health.
How Much PQQ Is in Food?
A landmark 1995 study published in the Biochemical Journal (Kumazawa et al.) used gas chromatography-mass spectrometry (GC-MS) to measure free PQQ levels across 20+ food samples. The results showed a wide range — from as low as 3.7 ng/g in some vegetables to as high as 61 ng/g in fermented soybeans (natto). A more recent 2018 study in PLOS ONE (Noji et al.) confirmed these findings using enzymatic and LC-MS/MS methods.
To put this into perspective: the typical daily PQQ intake from a balanced diet is estimated at only 0.1–0.3 mg, which is far below the amounts used in clinical supplementation studies (10–20 mg/day). This gap between dietary intake and therapeutic dosage is one reason PQQ supplements have gained attention in the nutraceutical market.
What Foods Contain PQQ?
Foods high in PQQ include fermented foods, green leafy vegetables, grains, nuts, and meats. A balanced diet is essential. PQQ is a nutrient with antioxidant and cellular energy metabolism functions. The following foods contain trace amounts of PQQ.
- Fermented foods: Some fermented foods, such as fermented tempeh, fermented soy sauce, and red rice wine, contain relatively high levels of PQQ.
- Green leafy vegetables: Certain green leafy vegetables, such as spinach, bitter greens, and mustard greens, are also high in PQQ. While moderate intake can benefit human health, avoid excessive intake, as it can burden the digestive system.
- Cereals: Cereals such as brown rice, barley, and oats also contain high levels of PQQ. Eating them in moderation can help improve memory. Beans are also commonly used to supplement PQQ.
- Nuts: Pine nuts, walnuts, flax seeds, peanuts, sesame seeds, and pumpkin seeds are also rich in PQQ. PQQ has potent antioxidant properties, neutralizing free radicals and reducing oxidative damage to cellular tissues.
- Meat: Meats such as beef, pork, and chicken also contain high levels of PQQ and can be consumed in moderation daily.
PQQ Content Data by Food Category
For those who want more detail: below is a summary of measured PQQ levels in specific foods… Note that this table only includes foods with quantified data — some categories mentioned above (whole grains, nuts, meats) contain trace amounts of PQQ that have not been precisely measured in published research.
| Rank | Food | PQQ Content | Category | Source |
|---|---|---|---|---|
| 1 | Natto (fermented soybeans) | 61 ng/g | Fermented | Kumazawa et al., 1995 |
| 2 | Vinegar (type H) | 5.59 ng/mL | Fermented | Noji et al., 2018 |
| 3 | Vinegar (type F) | 3.10 ng/mL | Fermented | Noji et al., 2018 |
| 4 | Vinegar (type G) | 2.38 ng/mL | Fermented | Noji et al., 2018 |
| 5 | Vinegar (type E) | 1.94 ng/mL | Fermented | Noji et al., 2018 |
| 6 | Oolong tea | 1.84 ng/mL | Beverage | Noji et al., 2018 |
| 7 | Rape blossoms | 1.41 ng/g | Vegetable | Noji et al., 2018 |
| 8 | Parsley | 1.37 ng/g | Vegetable | Noji et al., 2018 |
| 9 | Spinach | 0.71 ng/g | Vegetable | Noji et al., 2018 |
| 10 | Beer | 0.63 ng/mL | Beverage | Noji et al., 2018 |
| 11 | Green tea | 0.27 ng/mL | Beverage | Noji et al., 2018 |
| 12 | Tomato | 0.19 ng/g | Vegetable | Noji et al., 2018 |
Note: Reported values vary between studies due to differences in fermentation strains, analytical methods, and sample preparation. The highest value for natto (61 ng/g) comes from the original 1995 GC-MS study by Kumazawa et al.
Key takeaways from the data:
- Fermented foods dominate the top ranks. Natto and traditional vinegars consistently show the highest PQQ levels, supporting the role of microbial fermentation in PQQ production.
- Oolong tea outperforms green tea by nearly 7x (1.84 vs 0.27 ng/mL), likely due to its partial fermentation process.
- Green pepper contains no detectable PQQ in controlled studies, despite being cited as a PQQ source in some popular articles.
PQQ’s Effects on the Nervous System
With the accelerating pace of life and work and the increasing workload on the brain, the incidence of neurological diseases is increasing. PQQ influences nervous system development, endocrine regulation, metabolism, and cognitive function, and therefore, its role in neurological health has attracted considerable attention.
It is important to note that while these foods contain many essential nutrients, they should not be consumed all at once. Since PQQ is present in low levels in the daily diet, other methods of supplementation are necessary.
Using PQQ supplements is a well-known and effective way to meet daily PQQ needs. PQQ supplements contain high concentrations of PQQ, allowing for quick and convenient delivery of the nutrients you need. Avoid excessive intake to avoid intestinal burden.
Why Dietary PQQ May Not Be Enough
For individuals specifically seeking PQQ’s neuroprotective, anti-aging, or mitochondrial benefits, dietary intake alone is unlikely to reach the levels shown effective in research. This is why PQQ supplementation — typically as pyrroloquinoline quinone disodium salt — has become a growing category in the nutraceutical industry.
Looking for high-purity PQQ for your product formulation? Learn about our PQQ disodium salt →
The Significance of PQQ for Brain Health
Research has shown that PQQ can increase neurotransmitter levels in the brain, improving cognitive function. Furthermore, PQQ can stimulate neurogenesis, reduce neuroinflammation, and enhance antioxidant capacity, all of which are crucial for maintaining brain health. PQQ can also reduce fatigue, boost immunity, and improve sleep quality. It also has excellent benefits for liver health, cancer prevention, and beauty.
For your health, take action and supplement with PQQ scientifically and effectively.
If you have any questions, please feel free to ask → sunqian0123@gmail.com
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