How Many Calories Should I Eat to Lose Weight?
Find a sustainable deficit from estimated maintenance, keep protein high, and use our interactive calculator based on the Mifflin-St Jeor equation.
Your weight-loss calorie target is not a meme you saw on social media—it is your maintenance calories minus a sustainable deficit, with protein held high so you lose fat, not muscle. Written by Dr. Lisa Park for The Meal Preps (themealpreps.com), where the math behind every bowl is already done for you.
Read this alongside our complete weight loss guide for habits and training, and use the 30-day plan when you want a week-by-week checklist.
The short answer
Most adults do well losing about 0.5–1 lb of fat per week on roughly a 500-calorie daily deficit. Smaller deficits feel easier; larger deficits work short term but raise adherence risk. Your exact number should start from an estimated maintenance (TDEE), then adjust based on real-world weight trend after two to three weeks.
Calculate maintenance (then subtract)
The Mifflin-St Jeor equation estimates resting metabolism using age, sex, height, and weight. Multiply that by an activity factor to approximate TDEE. It is not perfect—thyroid issues, sleep, steps, and NEAT all move the number—but it is the best free starting point most coaches use.
Calorie & protein estimator
Uses the Mifflin-St Jeor equation for BMR, then multiplies by activity. For medical conditions, work with your clinician—this is a planning tool, not a prescription.
Estimated maintenance
2300
kcal / day (TDEE)
Your target
1800
~500 kcal under maintenance / day
Daily protein (starting point)
165 g
≈ 3.9 × 6 oz grilled-chicken bowls at ~42 g protein each
Activity multipliers
Sedentary multipliers underestimate people who walk a lot, and "very active" multipliers overestimate people who only train hard three hours per week but sit otherwise. Pick the honest description, then let the scale tell you if you were right. If weight is flat after three weeks in a claimed deficit, you are not in a deficit—either intake is higher than tracked or maintenance was underestimated.
How big should the deficit be?
A 500 kcal deficit is the classic one-pound-per-week anchor. If you are smaller or already lean, 300 kcal may feel better. If you have more weight to lose and high adherence, 600–750 kcal can work—but watch strength, sleep, and hunger. When any of those break, the deficit is too aggressive for your current life load.
Protein is non-negotiable in a deficit
Protein preserves lean mass, increases satiety, and has the highest thermic effect. In a deficit, treat protein like a daily minimum, not a bonus. If you struggle to hit it, pre-portioned meals remove the guesswork: see meal prep for weight loss and weekly plans.
Why week one lies
Early scale drops often reflect glycogen and water shifts, especially if you cut refined carbs and sodium. That is not "fake" progress—it is just not all fat. Judge trends over 3–4 weeks using averages, not single weigh-ins.
When to recalculate
After 10–15 lb lost, rerun your estimate. A lighter body burns fewer calories at rest and during movement. If progress stalls while adherence is solid, a small adjustment (100–200 kcal or +2k steps) usually restarts movement without drama.
Next step
Use the calculator above, set protein first, then build bowls that match your targets. If you want belly-specific context, add belly fat science.
FAQ
- Is the Mifflin-St Jeor formula accurate?
- It is one of the better population estimates for resting metabolism, but real TDEE varies with NEAT, sleep, and stress. Use the estimate as a starting point and adjust based on weight trend after two to three weeks.
- Should I eat back exercise calories?
- Trackers often overestimate burn. A conservative approach is to treat formal exercise as a bonus for adherence, not a license to add large calorie refunds, unless you are an endurance athlete with high volume.
- What is the smallest safe calorie deficit?
- There is no universal minimum—medical conditions matter. For generally healthy adults, small deficits of 250–300 kcal are gentle; aggressive deficits below roughly 1200 kcal/day for many women or 1500 for many men deserve professional oversight.
- Why do calories need to drop again after losing weight?
- A lighter body burns fewer calories at rest and during movement. Re-estimating maintenance every 10–15 pounds keeps progress honest.
- Can I lose weight without tracking calories?
- Yes—by controlling portions, increasing protein, and removing hyper-palatable foods. Tracking is a training wheel that many people later replace with habits. Pre-portioned meals are another way to cap calories without logging.