A low-carb diet limits food high in carbohydrates, like breads, pastas, and sugary desserts, and replaces them with fats and proteins. Foods high in carbohydrates are often high in calories and low in fiber, protein, and vitamins, so you are getting rid of the biggest culprits when it comes to weight gain. Eliminate these foods, and you’re likely to see an overall decrease in calories without having to track them. If food journaling sounds horrible, then low carb is easy enough it can be done in your head (though we’d still recommend keeping a journal for the first few weeks).