Hello! I think that you have the right idea about "dieting." As someone who has gained and lost weight, I will tell you that after a "diet" it can be easy to put those pounds back on! I follow the "Blood Type" diet, but it is merely a guideline of the foods that are good for my body type. I will tell you what has worked for me in the past and currently is working for me is to only put things into your body that are natural foods. Basically, if there is a huge list of ingredients on the back, DON'T EAT IT! I am not saying eat all organic or anything, but just put things into your body that you know are not over processed. I don't eat anything that has high fructose corn syrup or wheat. When you are giving your body all of the right nutrients, you are not as hungry because your body is getting all that it needs. That makes it easy to cut portions sizes. I start small by making small changes for cutting portions, because I like to eat!
One thing that I did was replace butter on my rice toast with organic, reduced sugar jam. It's the little things! Also, exercise for me is key. If I don't exercise, I lose no weight. Those people that can just diet and lose weight baffle me, and I am secretly a bit jealous! LOL! Well, hope this helps a little!