When people ask me about eating for fat loss, I always say that the first two things you should do are eliminate gluten and eliminate foods and drinks high in sugar. Why? These steps will give you the fastest results in the shortest amount of time and will increase your motivation to continue building healthy habits. Is this all you need to do to get ripped? No, of course not, but start by making small, sustainable changes. Incorporate habits that you can build upon instead of going all in for a week then falling back on your old habits.
Are there people that eat sugar and gluten all the time and are still lean? Certainly, but they're not doing themselves any favors and it's only a matter of time until a diet like that catches up with them. Don't base your diet on the genetic outliers. That's like spending your paycheck on lotto tickets because you know someone who hit the jackpot. Besides, external appearance isn't always reflective of internal health.
What if you already abstain from those foods? Well you’re already ahead of the curve and this article in not written for you. That being said, you’d be hard pressed to find an overweight American who doesn’t have a significant amount of gluten or sugar in the diet (read my opinion on gluten-free diets here).
These rules are very simple and easy to follow. If it's high in sugar or has gluten, don't eat it (for now). Make this an opportunity to expand your usual menu and find new foods that you like. You'll start to realize how limited the standard american diet is once you begin to branch out with your food selection.
I think a lot of people go wrong when they focus on making a lot of small changes that yield very limited results. For example, if you think that adding a sprinkle of cinnamon to your oatmeal will make a meaningful difference to your insulin response, then you are delusional. What difference will that make if you’re still going way over your carbohydrate needs? Or my favorite, switching from white bread to “whole wheat” bread. Again, complete waste of time. You will not see or feel any difference from making a change so small and insignificant! It’s like trying to save money by turning off the lights in your house. You might save a few dollars by the end of the year, but that will have zero impact on your quality of life. Don't even get me started on the so-called "fat burner" supplements which should be just about dead last on your list of priorities when it comes to fat loss nutrition.
The bottom line is, focus on making the big meaningful changes first, and then worry about tweaking the small things to optimize your diet. Once you start seeing the changes in your physique, you will have plenty of motivation to continue making positive changes.