Popular culture has always framed dieting as something you do for a short period of time to get the results you want. "6 Weeks to 6-Pack Abs," "The 8-Week Shred," etc. You can imagine the magazine and book covers right now, with bold yellow letters and one or two picture-perfect models. Don't get me wrong, I'm positive if you followed their plan you could get some decent results, but certainly not the picturesque body physiques they love to advertise.
The funny thing is, once you actually understand how the human diet works, you figure out that the way most people think about diets is entirely wrong. You're not supposed to "diet" for six or eight weeks at a time to attempt to lose weight or maintain a good state of health. Let's think about it in an easy example.
You don't go to work six weeks out of the year and expect to have a salary you can live off of all year long. So why would a reasonable person expect a diet you try for six weeks to keep you in shape all year round? Timed dieting doesn't work, because dieting is a long-term game (of course there are exceptions, but this applies to most people). You should think of your diet like it's a math equation, "oh this is a diet I have to do X amount of time to get Y result."
Lifestyle is the biggest factor in impacting your overall diet. Consistency is key in all aspects of fitness, and most importantly, fitness. It's easier to eat healthy foods most of the time and enjoy yourself every now and then than it is to be 100% strict five days a week then crash on the weekend. This is what flexible dieting is, and it allows you to go out with your friends to eat or eat that cookie your friend gives you without feeling guilty. As my favorite fitness influencer Jordan Syatt says, you're never more than one bite from being back on track.
Integrating the habits of healthy eating into your routine makes healthy eating a lifestyle component, not something you have to crutch yourself to. Lifestyles are long-lasting and maintainable, but "diets" as most people know are not. "But what about keto/high protein/fill-in-the-blank diets?"
Here's my honest opinion – 95% of people who attempt fad diets go back to their old ways of eating before they see any progress. I'm not hating on keto or any other style of popular diets people want to try. At the end of the day, it's about how maintainable that diet is for them. If you can deal with a low carb diet that's cool, more power to you. For myself and most people, restraining myself that much would drive me crazy.
Dieting basics are simple. Find out how many calories you can consume per day without gaining or losing weight. If you want to gain weight eat in a healthy calorie surplus, or if you want to lose weight eat in a deficit (~400 calories). You should never have to starve yourself or overeat if you want to change your weight because if you think in the long term, 10 pounds is easy to do over the course of six months. It's all about the long-term, the maintainable.
In the course of my five-year fitness journey, I have tried just about every style of dieting to see what works best for me. I personally abide by a high-protein diet because I am a heavy weightlifter and want to build muscle all year round (this also means I track my macros). Going with a diet where I eat my bodyweight in grams of protein has never done me wrong because protein is essential for muscle building and is incredibly satiating. As far as my fats, I try to eat healthy fats only and fill in my carbs around convenience. I must be proactive through this approach to gain unhealthy weight.
When it comes to dieting, find out what you need to do long-term to have the body you are proud of. Fad diets and words plastered on the front of magazines probably aren't going to work for you, but if you can find a way to make it fit your lifestyle, then, by all means, be creative. Otherwise, find what you can maintain and stick with it.