Collage by Cam Howard, 2016; Berberis vulgaris by Dr. Otto Wilhelm Thomé / public domain; Curcuma longa by Simon A. Eugster / CC BY-SA 3.0; Gymnema sylvestre by Lalithamba / CC BY 2.0

Berberine (from barberry, top left), curcumin, and gymnema sylvestre (right) can help regulate blood sugar. Lowering blood sugar can improve many issues: mood, memory, weight, and energy.