In a randomized, double-blind, placebo-controlled crossover trial, 50 adults with coronary disease or ≥ 1 cardiac risk factor received muscadine grape seed supplementation ( 1300 mg daily ) and placebo for 4 weeks.

In a randomized, double-blind, placebo-controlled study of older, non-demented men & women, soy isoflavone supplementation improved performance on 6 of 11 cognitive tests, including visual-spatial memory and construction, verbal fluency and speeded dexterity ; unexpectedly, the placebo group performed better on 2 tests of executive function.

In a randomized, double-blind, placebo-controlled study of 18 healthy volunteers, 600 mg of ' Melissa officinalis ' extract attenuated volunteers ' response to a laboratory-induced stress test 1 hour after administration ; 300 mg significantly improved speed of mathematical processing 1 hour after administration.

0.004 seconds.