One of the most common diets is the low-carb or even zero-carb diet. While protein and fats are essential to live and be healthy, carbohydrates are not, so if a low-carb diet was followed correctly, it wouldn’t have any serious health consequences. However, for most people, it just isn’t realistic to give up carbs completely for any long period of time. You’ll have to eat extra fats to make up for those lost calories, and unless you’re careful, it’s easy to eat too much of the wrong sorts of fats and end up with health issues down the road. You may also find yourself short on a lot of micronutrients if you limit things like fruits and vegetables.
Unless you are following a carb-cycling diet, which is not necessary and is a bit more advanced, it’s probably best to avoid low-carb diets. It’s not an unhealthy option and in theory it makes sense. However, giving up carbohydrates for good just isn’t realistic for most people, and it would be more beneficial to learn to follow a balanced diet. The best diet is the one you can sustain for a long time.