As we all know -or should know- parrots livers are their weakness. Life in captivity [stress, lack of exercise, bad diet, etc] makes fatty liver disease one of the most common problems that parrots have -even young one!
These articles are all meant for humans but the disease [non-alcoholic hepatic steatosis] is the same that parrots get. It has the same symptoms, the same prognosis, the same treatment... pretty much the same everything. So extrapolation of information is very useful for us, parrot keepers.
The first link is actually something that surprised me because it states that one single real bad meal can cause damage to the liver and I thought it was VERY important to share it with you because birdsites are all full of the 'moderation is the key', 'one single piece is not going to harm the bird', etc. etc. etc. conveniently forgetting that, with the exception of two and possibly three species, all parrots are herbivores which mean not only that they do NOT consume high fat but that they do NOT consume animal fat! Well, this knocks the belief right out of the park, doesn't it?
https://www.cbsnews.com/news/even-one-h ... our-liver/
The second link is also very important because it shows the connection between internal organs and tells us that when one organ is affected, the other internal organs also suffer. Of particular interest is the effect fatty liver has on the pancreas and, subsequently, on the immune system.
https://www.sciencedaily.com/releases/2 ... 102308.htm
The third link is about bananas and liver health but, if you think about it, it's not about just bananas but about the effect of fruits high in sugar on fatty liver. We all know -or should know- that birds should not consume too many carbs but that has loosely been translated to mean that fruits high in sugar are not good for them when this is simply NOT true. What parrots should NEVER consume is sucrose [an ingredient found in some very low quality pellets!] but fruits high in fructose that are also high in fiber and moisture are not bad for them at all!
http://www.liversupport.com/debate-bana ... -wellness/