on a more personal note....
I became vegetarian at age 14 after reading Frances Moore Lappe's book "Diet For A Small Planet". Over the years, I had short phases of eating small amounts of fish and chicken but never read meat. I had minimal protein, a little yoghurt at best, and ate almost no processed foods. At 24 I had my first gallbladder attack. Liver flushing transformed my health almost over night and where I had been eating some fish, I returned to a vegan alkaline diet. 9 years later (last year), I started seeing a wholistic doctor for a hormone imbalance (high estrogen, low progesterone, zero testosterone). Flushing had radically improved my menstrual cycle but I was having hormonal flushes which caused vomiting and extreme tiredness. The doctor explained that I needed animal fats for my body to synthesize cholesterol and therefore make hormones. I was finally convinced when I attended Sally Fallon's lecture (co-author of cookbook "Nourishing Traditions") on cholesterol and fat.
I'm sure I already had liver problems due to all the usual reasons (vaccination, processed food, anger, etc) but I felt I must have exacerbated the condition by becoming vegetarian. You mention low-fat diets can also cause gallstones so perhaps my diet was too low fat. I don't fit the textbook gallstone case (fat, female, forty). I've never really drunk much alcohol, never taken drugs, always favoured natural foods to processed foods, been vegetarian and sometimes vegan, etc etc). So perhaps then you can understand my confusion about how best to proceed with my diet.
Thank you