It seems the best thing is to be reasonable. For example, eat a variety of foods from different food groups. Try to expand your pallette. Eat a fair amount of fruit and veg. Ideally, whatever you eat will fit in your lifestyle.

For me, I found a few things (and I've actually lost weight and kept it off for years):

Mostly vegetarian works for me - I eat fish a couple times a month. I had gall bladder problems, though, and have had it taken out. This works well for my body and I like the food. I cook at home 95% of the time. I skip breakfast (I'm not hungry!). I use butter and cream. I also walk often.