Great product, essential for collagen production and the absorption of iron to make new red blood cells. Look up Dr Berg's video on copper to understand its function, "mainstream science" conveniently does not tell you how these micronutrients work and how ESSENTIAL they are to overall health...Who knew one could be deficient in copper!?! I didn't. Once i realized that I was, and what this deficiency was doing to my mental capacity i bought this for brain function as it is in the same form (copper citrate) as in a combo supplement i am taking.I bought this product because it got high reviews and was a very fair price. I sometimes desired not to take my combo supplement (because my combo also had ingredients for hair nails skin etc.) So Sometimes i just wanted a brain support supplement. I am very pleased with this product. It has the same noticed effect on my brain function as with the combo supplement. It has the same dosage as my combo, 4mg.For me personally, my deficiency in copper prevented me from being able to think clearly or more specifically, in a seemingly linear or organized fashion. Once i started taking copper, i could instantly get myself out of “circular” thinking patterns which went nowhere. It also makes me feel happier and have a better, more optimistic outlook on life. I handle stress better because i am able to think positively with way less effort than before. Before taking copper I felt as though I was forcing myself to think positively or even logically at times. Prior to taking a copper supplement i "knew" that i wanted to think positively, but sometimes could not remove the negative thought pattern or if i did, it lasted only a few minutes. I had no idea that a deficiency in copper could make one feel somewhat akin to mild depression!I suppose in hindsight i knew that copper was an excellent conductor and that's why it's used in circuit boards and the human brain is somewhat like a complex arrangement of circuit boards with neurons needing to transmit information from one cell to the next (in its most basic and general terms). My copper was depleted from 3 back-to-back pregnancies. This is how i stumbled unto it, my husband purchased a combo supplement for my hair nails and skin (which contained 4mg copper per serving) to help them return to their pre-pregnancy luster, so i very much stumbled unto the copper thing!In summary, this product has majorly improved my brain function, I think more clearly and logically and i happily recommend it! I've already ordered more as I take it regularly.Easy to swallow and take with food or withoutThe body needs copper for a number of functions. I have been trying to gauge its effect by the observable. Taking the recommended dose with Zinc ( the two work together) I still have a few gray hairs on my head. That said, I have noticed the gray strands diminishing in my beard (only shave once a week to observe effects on facial hair). I am unsure if I should increase the dose, to attack the gray hairs on my head. Requires more research. Overall though, I have had very favorable results with other Pure Encapsulations citrate products and remain confident about the potential of this product. Maybe I should see if they have a Zinc citrate too? : )Doctor prescribed to balance my high zinc intake required for liver problems. Micronutrients and hematology tested every six months, and only three brands actually work: Jarrow Formulas, Pure Encapsulations and Ortho Molecular, but Pure Encapsulations clinically proved to work the best on me after years of trial and error.Health Reasons!I started to take copper because I'm deficient in iron. I read symptons of copper deficiency and was shoked how many symptoms I had! I also have M.S. so many symptoms of copper deficiency can mimic M.S. I also started taking it because if someone is iron deficient and copper deficient the iron isn't absobed as it should be without copper levels being up too. I've only had the copper for two days so itll take time to feel better. I pray this is my answer!Just be careful not to take too much. Monitor your levels. Had an amazing effect when I first started taking it, because I was low in copper but after about 2 weeks, it started making my copper levels too high and I started getting twitchy from it.