PQQ safety studies in humans have been conducted in preparation for several human use patents. Pyrroloquinoline quinone was administered at 20 or 60 milligrams per day to healthy adults given either a PQQ supplement or a placebo. No adverse effects were observed in standard clinical tests at either dose (e.g. glucose, triglycerides, and various lipoprotein fractions); In fact, parameters related to lipid metabolism improved and inflammation improved. Functional tests for liver toxicity and kidney function were also normal.
The single-dose oral toxicity tests in rats indicate the approximate lethal dose of PQQ is above 500 milligrams per kilogram of body weight (per day). To put this toxicity level in perspective, the oral toxicity for the water-soluble vitamins:
- ascorbic acid
- riboflavin
- pyridoxine
…are all 10 to 20 times greater. In human terms, the 500-mg/kg dose, when appropriately corrected for metabolic body size differences (rat vs. human), would extrapolate to about 35-50 grams per day or over 1000 times the effective physiological dose (10-20 mg/day).
[…] at this point, 10 to 20 milligrams per day seems to improve exercise tolerance in humans as well. Since PQQ (pyrroloquinoline quinone | methoxatin) has been shown to be safe at this amount (10 to 20…, it is currently the amount you will find in most supplement formulas. CATEGORY: PQQ Information […]