Copper Linked to Better Brain Function In Old Age https://www.sciencealert.com/copper-linked-to-better-brain-function-in-old-age-diet-study-suggests The 1.22 mg copper per day is the equivalent of a handful of walnuts or a bowl of lentils. Copper is found in more foods than you might think – including mushrooms, dark chocolate, wheat bran, and oysters