PQQ, short for pyrroloquinoline quinone, is an essential nutrient that the human body must obtain from food.
It is a coenzyme of oxidoreductase, and its unique o-benzoquinone structure endows it with many different physiological properties from other coenzymes, and also makes it have different physiological functions.
PQQ occurs naturally in soil and is also produced by soil bacteria. Plants absorb it and we get it by eating plants. In addition, some bacteria in fermented foods and beverages produce PQQ.
PQQ is present in all tissues of the human body, is concentrated in breast milk (140 to 180 ng of PQQ in milliliters of breast milk ), and is a growth factor necessary for development. Animal studies have shown that a deficiency in PQQ stunts growth, impairs immunity, and causes reproductive and metabolic problems.
PQQ optimizes mitochondria to support energy production
The human body is made up of about 37 trillion cells, each of which contains 300 to thousands of mitochondria.
Mitochondria serve as the power source of cells, converting food and oxygen into energy. But mitochondria don't just produce energy -- they're essential for the survival and death of cells in the body.
They are also critical for healthy communication between cells and play an important role in removing abnormal cells, such as cancer cells.
Research has shown that healthy mitochondria play an important role in supporting important markers of cognition, fitness and aging.
But as we age, they deteriorate and die - which is the main reason why children have more energy than their parents and grandparents. Damaged and reduced mitochondrial numbers are implicated in many diseases of our time, from Alzheimer's and Parkinson's to chronic fatigue, heart failure to diabetes.
PQQ is unique in that it increases the number and quality of healthy mitochondria in senescent cells . Relevant human studies  show that the improvement of mitochondrial function indicators can be observed after taking PQQ for only 3 days.
In addition to improving energy production, this property of PQQ can slow down some aging processes.
In a UC Davis study , researchers administered PQQ supplements to 10 people (5 men and 5 men) and tested their effects after 76 hours. Using blood and urine tests, the researchers found that PQQ improved mitochondrial performance and reduced chronic inflammation. An effective dose is 0.3 mg PQQ per kilogram of body weight, eg, 20 mg PQQ for a 150-pound person.
PQQ supports "short-term memory" and various brain functions
The mitochondria of nerve cells in the nervous system and brain degenerate over time. In addition to impairing memory and attention, mitochondrial degeneration has also been linked to diseases such as Alzheimer's and Parkinson's. By regenerating mitochondria, PQQ can help prevent or even reverse this damage.
A study of 41 elderly Japanese  tested the effect of PQQ on mental functioning. Over a 12-week period, study subjects were divided into two groups that received either 20 mg of PQQ or a placebo. Cognitive tests showed that PQQ improved memory and concentration, and brain scans found increased blood flow.
Another 6-month double-blind trial in 65 elderly people  showed that PQQ combined with coenzyme Q10 has a more obvious effect on improving cognitive function.
Q10+PQQ improves cognition
On the other hand, PQQ molecules can stimulate the production of nerve growth factor (NGF), and NGF, as a small protein, can protect nerve cells and support healthy nerve cell growth .
Other studies of PQQ
Improved sleep and lower cholesterol are other benefits of PQQ that have been confirmed in human studies.
A study of 17 men and women found that taking 20 mg of PQQ daily for 8 weeks helped people fight chronic fatigue and mental stress.
Continued use of PQQ can relieve sleep disorders caused by anxiety by reducing the stress hormone cortisol, effectively reduce the time to fall asleep, and improve sleep quality. 
Another study administered the PQQ test to a group of 29 adults between the ages of 40 and 57 with elevated triglycerides and cholesterol. Taking 20 mg of PQQ daily for 2 weeks did not change triglyceride levels, but lowered levels of harmful LDL cholesterol. 
The best way to benefit from PQQ
Studies typically use 20 mg per day, or 0.3 mg per kilogram of body weight.
To calculate your daily dose, divide your weight (in pounds) by 2.2 and multiply by 0.3.
As an example, the dose for a 180-pound person is 24 mg: 180 divided by 2.2 (82) times 0.3.
Plant-based foods generally contain very small amounts of PQQ, such as natto, spinach, green tea, parsley, green peppers and kiwi fruit are the most important food sources. To supplement 20mg of PQQ, you need to eat the equivalent of 4 tons of tomatoes or 330 kg of natto.  (1mg=106ng)
In addition, PQQ and Q10 can act synergistically when taking Q10 at the same time , because they are both optimizers acting on mitochondria.
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