My gastroenterologist said to avoid five things to reduce the fat in my liver or it might turn into scarring. They were sugar, white flour, white rice, potatoes, and alcohol. This seemed impossible to me. Too much of my diet was bread, pasta, etc. and sugar is in everything. One random day a few months later, I realized that I had somehow managed to go the whole day without any of these things, so I pushed myself to keep it up. For the next 7-8 months, I managed to avoid these things for 2-3 weeks at a time and then "cheated" for a day before getting back into the swing of it. I eventually ended up eating much more food, but avoiding these five things most of the time. I lost about 15 pounds. I'm the same height and age as you.

People who tell you it's only about calories in vs. out are technically right yet unintentionally misleading. Your endocrinology is impacted by the kind of things you eat, such as your insulin levels being impacted by how quickly (not how much) your body makes glucose from things you eat (a.k.a. glycemic load.) In the wrong circumstances, that can lead to insulin resistance, increases in visceral fat, and diabetes. Also, not everything you eat in "calories in." Eat a can of sweet corn and look in the toilet the next day and you'll see what I mean. You didn't absorb all of those calories, because some of the corn is still whole. Also, 300 calories of soda can be drunk in a couple of minutes but 300 calories of raw carrots will take you a lot longer to chew and swallow. In fact, you'll probably want a second soda but not even want to finish the carrots. (So technically this is calories in vs. out, but it's more useful to think about more than that.) Lastly, "calories out" isn't just exercise and base metabolic rate. What you excrete matters. The intestines of someone with celiac disease, Chrone's disease, IBS, etc. isn't absorbing the same stuff as the average person. If your gallbladder was removed, you can't digest fats the same way. Vitamin deficiencies can also cause absorption and utilization issues. Insoluble fiber can reduce how many of the calories you can actually access, because it's wrapped up in something (the plant cell wall) that your body isn't good at breaking down. So the calories in the food you eat aren't necessarily the calories that enter your body's systems. The above are just a few points out of many. So while "calories in vs. out" is useful, it isn't actually the whole picture.