Vitals Quercetin-PS (60 capsules) is a potent supplement containing quercetin, one of the most prominent bioflavonoids known for its presence in apples, berries, brassicas and onions. Quercetin, belonging to the subgroup of flavonols, plays a role in the natural protection of plants. Vitals Quercetin-PS improves the daily intake of quercetin by combining it with phosphatidylcholine, resulting in significantly better absorption and bioavailability.