Digest Histamine – DAO (or Diamine Oxidase) is an enzyme that is naturally present in the gut and plays an important function in metabolizing dietary histamine ingested from food.*Powerfully Potent – Solaray DAO Enzyme supplements are plant sourced from pea sprouts and are designed to supply 60,000 HDU, or Histamine Degradation Units.Enteric Shield – Our DAO supplement is made with an enteric coated capsule, which helps the ingredients survive the stomach acid and pass into the small intestine for better utilization.*Making a Difference - To reduce our carbon footprint, Solaray bottles are made from post-consumer recycled resin, helping keep plastic out of our landfills and oceans; we’ve also installed solar panels as an additional energy source at our Ogden, Utah facility—to power the processes and products that help you Live Brighter.Trusted Brand - Vegan, made in our GMP-certified facility, and always tested in our own state-of-the-art lab in Utah to bring you the best possible quality.