Two things a coach or trainer can help you with
The amount of knowledge fitness professionals have about eating for weight loss that long time dieters don't is much less then you might think. If you've been trying to lose weight for years, or even decades, you know the mechanics of most “if not all” of the popular diets. Plus, you have hands on experience on how each of the plans you’ve tried to follow have fit into your day-to-day life, which is most important.
One thing a coach, trainer or whatever other title they go by CAN help you with is how to make adjustments to your decision making when things don’t go according to plan. Since they have context for your preferences, routines and situations they can help you come to the right decision for you faster than you would on your own. Think of us as the training wheels for showing you how to make your active lifestyle one that you’ll actually want to stick to. Eventually, you’ll trust yourself enough to where you won’t need us. A topic for another post is making sure the professional you work with has an exit strategy that includes a wind-down period.
Another thing you'll pick up from your fit pro is their personal mental approach to eating, exercise, lifestyle management and how this ties into how they view themselves. If you don’t want to approach all this stuff in a similar way they do, you should consider working with someone else. While we’re talking about this, never forget that YOU CAN ALSO DO ALL OF THIS ON YOUR OWN. It will take longer this way, which isn’t always a bad thing because we’re talking about connecting with yourself and figuring out how to do this stuff for life. That takes time and can also be very enjoyable.