How to Set Your Macros for Weight Loss, Maintenance, or Muscle Gain
Calories decide the direction, lose, maintain or gain. Macros decide what you actually eat to get there. Both matter, and both are covered by our own tools: BMR and TDEE Calculators for the calorie side, our Macro Calculator for the split. Here is how to actually use all three together.
Start with your real number: BMR and TDEE
Your BMR is the energy your body burns at complete rest, just staying alive. Your TDEE adds your real activity level on top of that, the actual number that reflects how many calories you burn in a typical day. Work out your own real figures with our BMR Calculator and TDEE Calculator before setting any goal.
The real math behind a daily 500-calorie goal
One pound of body fat holds roughly 3,500 kcal, so a 600 kcal daily deficit or surplus works out to a little over a pound, roughly 1.2lb, a week of change. That is the real default adjustment our own BMR/TDEE tool applies for its Lose or Gain goals, deliberately matching the NHS’s own current official guidance: its Better Health service states, “Aim to reduce your intake by around 600 calories a day,” framing that as “a safe and sustainable way to lose weight.” A stricter 500 kcal a day, the older, simpler 3,500-kcal-per-pound rule of thumb on its own, is also a common, real approach elsewhere, just not what this tool defaults to.
Then decide your macro split
Once you have a real daily calorie target, the split of that target between protein, carbohydrate and fat is what our Macro Calculator works out, see our full explanation of the three splits for the numbers behind each. As a practical starting point: Higher Protein is commonly chosen when trying to preserve muscle during a deficit or support muscle gain, since real protein needs go up with both of those goals. Balanced works fine for most people simply maintaining. Lower Carb tends to come down to personal preference and what you find easiest to stick to.
This article is general information, not personalised nutrition or medical advice. If you have a specific health condition or goal, speak to a registered dietitian or your GP.