"Monosodium Glutamate - promoter of liver inflammation"
There is a big amount of research out there, studies and other medical articles. But this one is quite comprehensive and easy to understand.
It's not only about avoiding fats, sugars, fried stuff etc if you have PBC or any other autoimmune or inflammatory condition, it's also about the stuff you take in with food you think is ok for you (or doctors don't warn you about) but which on the long run, especially if your body is already facing a chronic condition, can only harm some more.
What foods you find aspartame and particularly MSG in - there is plenty of info online but also on food labels, if you know what to look for.
Want cheese? Don''t get fancy commercial brands but the most natural you can find. Want sweets? Make them yourself or have black chocolate or the similar simpler stuff. Want to drink? Water, tea, natural juices. Want meat? Avoid sausages, make yourself a steak or a steam boiled piece of meat or fish. Is not that difficult :).