Copper lowers histamine (so does zinc.  I think zinc more powerfully lowers histamine) Plasma Diamine Oxidase Activity Is Greater in Copper-Adequate than Copper-Marginal or Copper-Deficient Rats https://academic.oup.com/jn/article/130/1/30/4686063 Diamine Oxidase, a copper-containing enzyme, also known as histaminase, breaks down histamine. “What Is DAO? Diamine oxidase (DAO) is a digestive enzyme produced in your kidneys, thymus, and … Continue reading The Copper Revolution: Ch 11: Copper lowers histamine, and Ch 12: Copper, Great for the Skin