Effect of Dietary Pyrroloquinoline Quinone Disodium Salt on Cognitive Function in Healthy Volunteers: A Randomized, Double-Blind, Placebo-Controlled, Parallel-Group Study

Researchers gave 64 healthy adults, ages 20 to 65, either 20 milligrams of PQQ daily or a placebo, an inactive look-alike pill. The study lasted 12 weeks, and neither the participants nor the researchers knew who received PQQ until the end. Computerized tests measured memory and other thinking skills. The PQQ group improved on some memory tests, especially among participants over 40, but not every measure improved.

What this means for you: This small, short study does not show that most healthy people should buy PQQ for sharper thinking. The results need confirmation in larger and longer studies before PQQ can be recommended for memory.