Macronutrients

Not perfectly - but consistently. Being within 100-150 calories of your target most days is far more effective than occasionally being exact.

No. It only becomes useful for fat loss if the overall calorie intake stays controlled. Many people cut carbs and then add large amounts of cheese, oils, nuts, and fatty sauces, which can keep calories high even if carb numbers are lower.

Calories determine the deficit, but satiety often determines whether you can keep it. A plan with perfect math and miserable hunger usually collapses. The useful approach is to build meals that stay within the calorie target and still make you feel like you actually ate.

Lean chicken breast, turkey breast, white fish, tuna, low-fat Greek yogurt, cottage cheese, egg whites, and some lean beef cuts are usually among the most efficient. Whole eggs are still useful, but fattier cuts of meat and cheeses often bring much more calorie baggage with them. The best choice depends on taste and compliance, but lean protein sources usually make hitting the target easier.

A 300-500 calorie daily deficit is sustainable for most people and produces 0.5-1 pound of fat loss per week. Larger deficits are possible but harder to maintain without muscle loss and hunger issues.

Because a low-calorie meal without protein often feels empty fast. Protein helps the meal feel more substantial, supports satiety, and makes it easier to stay under control later in the day. A pile of vegetables without enough protein may look virtuous, but it often leads to snacking or second meals later.