I have lost over 30 pounds since late July with the easiest to follow "diet" I have ever used. The secret is to write down everything that you eat, and record it. I keep an electronic scale, that zeros out, and weigh
everything that I eat. I then enter the list into a web based calculator. I use the one at
SparkPeople.com, since it allows users to add products, and seems to have almost every available product listed, even those exclusively Canadian. I set a goal of 1600 - 2000 calories a day, since I work at a desk, and I am not very active. Note that while I use SparkPeople's website to total my lists, I do not follow their diet recommendations.
I started this after reading that in several published studies, those who kept detailed food diaries had markedly better results than those who didn't, regardless of the diets that they were on See:
http://http://healthland.time.com/2012/07/13/the-secrets-to-weight-loss-keep-a-food-journal-dont-skip-meals-eat-in/ and
http://www.sfgate.com/news/article/To-drop-pounds-write-down-everything-you-eat-3206644.php
What happens when you write everything down is that you remain mindful of what you are eating. You can't look at a list that includes three full bowls of cereal, that when weighed represent three official servings each, and believe that is sane. Yet I know that was something that I'd regularly do before. You can't write down that you ate one and a half (12 slices) of stuffed crust pizza @ 300 calories plus each slice, then enter it into the calculator, and believe that is OK. So it becomes self correcting. You don't want to embarrass yourself by doing stupid things, and after a while, you don't.
The beauty is, that I don't feel deprived. If I feel like a piece of pizza, I have it. If I want some Pringles, I eat them. But I force myself to write all of it down, and then enter them in the calculator, to see the result. Even if I have a hotdog at 7-11, I write it down, and I can find it on the SmartPeople calorie list.
I used to calculate them through the day. Now I wait till the next day. I found that if I had only eaten 1400 calories, I'd run to the kitchen and "top up" my list by eating something else. After doing this for a few months, I am amazed that often my list only totals 1300 - 1500 calories, even though I didn't feel hungry or deprived. The highest it has gone, after the first week, is 2,600 calories, and that is probably maintenance for me.
The problem with other diets I have tried, like Atkins or Low Fat, besides the fact that they seem to mess with your head, is that once you reach your goal, you are pretty much forced to go off of the diet, and back to your "regular" eating regime. With the "write it down" method, you never really changed your diet, you just changed the quantity that you eat. So going off of it doesn't involve any drama. You continue to eat the same things, just a little more of them.
This has really worked for me. I'd recommend it.