I've been taking 20g of collagen and additional amino acids daily for over a year after an Amino Acid test showed that I was deficient. Initially I suspected it was a dietary issue, since I didn't eat a lot of protein...it doesn't make me feel well due to my GI issues. So after supplementing, retesting, plus some trial and error, I finally improved the AA levels by increasing my choline and methylfolate supplements to address my underlying genetic variants. (See research articles on Folate-dependent EDS.) I also needed to address a genetic variant impacting my methionine levels and found that SAMe was helpful with that. So bottom line, collagen on its own did not help me until I fixed the underlying deficiencies. I'm continuing to take collagen but stopped the separate AA supplements as my levels improved. I'm continuing to work on correcting my GI issues and histamine levels to see if that will help speed along the repair of damaged tissues. Considering prolotherapy if the nutritional fixes don't give me the pain relief and improved mobility I'm hoping for.