TDEE for Weight Loss: The Complete Deficit Guide

Why TDEE is the anchor

Weight loss is, at the mechanical level, simple: eat fewer calories than you burn. The hard part is knowing what "burn" actually is. That number is your Total Daily Energy Expenditure, and it is the only input to any weight-loss plan worth following. Fancy diets — keto, intermittent fasting, carb cycling, paleo — do not break the energy-balance equation. They are all just different ways of helping you eat less than your TDEE.

So the first job is a realistic TDEE estimate. Most people overestimate it. A desk worker who trains three times a week is not "very active" — that is the moderate bucket. If you are sedentary most of the day, honestly pick sedentary, even if you run on weekends. Overestimating activity produces a too-high TDEE, which produces a too-high "deficit" target that is actually maintenance in disguise. Then the scale does not move and you blame your metabolism.

Picking the right deficit size

The textbook answer is 500 kcal below TDEE for roughly 0.45 kg (1 lb) of weekly loss. That is a reasonable default, but a percentage-based approach fits real bodies better:

• Conservative (10 to 15%): good for lean people (under 15% body fat for men, under 25% for women), women approaching a weight where hormonal disruption is a concern, and anyone who wants to preserve training performance. Expect 0.2 to 0.4% of bodyweight per week.
• Moderate (15 to 25%): the workhorse. Appropriate for most people with more than 5 to 10 kg to lose. Expect 0.5 to 0.7% of bodyweight per week.
• Aggressive (25 to 35%): reserved for people with significant excess weight (BMI above 30) or short, focused cuts of 4 to 6 weeks. Expect 0.7 to 1.0% of bodyweight per week. Not sustainable beyond a couple of months.

A 90 kg man with a TDEE of 2,800 kcal picking a moderate 20% cut eats 2,240 kcal/day. A 60 kg woman with a TDEE of 2,000 kcal picking a conservative 15% cut eats 1,700 kcal/day. Same approach, different absolute numbers — which is the point. A flat 500 kcal deficit would be 18% of the man's TDEE and 25% of the woman's. That asymmetry is why people on identical deficit protocols get wildly different results.

Protein first, then everything else

A calorie deficit is a stress signal. Your body can respond to that stress by burning fat, by burning muscle, or by burning both. What you eat and how you train decide the ratio. The single biggest lever is protein: a target of 1.6 to 2.4 g per kg of bodyweight (higher end for leaner people, lower end for heavier people) protects lean mass during weight loss, increases satiety, and has the highest thermic effect of any macronutrient.

For a 75 kg person, that is roughly 150 to 180 g of protein per day. Split across three or four meals, that looks like a palm-sized portion of chicken, fish, Greek yogurt, tofu, cottage cheese, or lean beef at each meal, plus a scoop of whey if you need to close a gap.

After protein is locked in, fat and carbs can be balanced to preference. Minimum fat is about 0.6 g/kg for hormone support. Everything else goes to carbohydrates, which fuel training and take the bulk of what is left after protein and fat.

The 14-day feedback loop

A TDEE calculator is a guess. Reality is the only verifier. Use this loop:

1. Estimate TDEE honestly and pick a deficit (start with 15 to 20%).
2. Eat that target for 14 days — not 4 days, not "most days". Weigh yourself every morning after using the bathroom, before eating or drinking.
3. Average your weight for days 1 to 7, and days 8 to 14. Compare the two averages.
4. If the second week is 0.3 to 0.7 kg lower than the first, your deficit is working. Continue.
5. If weight did not move, cut intake by 150 to 200 kcal.
6. If weight dropped more than 1 kg between the averages, add 100 to 150 kcal back. You are losing too fast for sustainability.

Two iterations of this loop — about a month — replaces any calculator. You now know your personal TDEE within 100 kcal.

Plateaus and how to break them

Plateaus are not failures; they are signals that TDEE has adapted. A plateau longer than two weeks, despite strict adherence, usually means one of three things:

• TDEE has dropped. Weight loss reduces both BMR and the calorie cost of activity. Recalculate at your new weight. The old 500 kcal deficit is now only 300.
• NEAT has cratered. Dieting tends to make people subconsciously move less. Fidgeting stops, posture gets slacker, daily steps drop by 15 to 30%. The fix is explicit: a step target (8,000 to 10,000/day) and brief walks after meals.
• Tracking has drifted. After 6 to 8 weeks of counting, most people start eyeballing. A 30 g portion becomes a 45 g portion. For a week, re-weigh everything that goes in your mouth.

If none of those fix the plateau, the answer is a diet break: eat at estimated maintenance for 7 to 14 days. This lets leptin, thyroid, and NEAT partially recover. When you resume the deficit, progress usually restarts.

When to stop cutting

Stop when you hit your goal weight or body-fat percentage. Stop, at least temporarily, if you are past 12 to 16 weeks in a deficit and progress has been slow for the last three of them. Stop if your sleep gets wrecked, your training numbers drop more than 10%, or your mood is visibly worse than baseline. Fat loss is slow; going faster by grinding through these signals usually does not end well.

The right end to a cut is a planned maintenance phase: eat at your new TDEE for 4 to 8 weeks. This consolidates the loss, rebuilds training capacity, and, if you want to continue, gives the next cut a clean starting point.