Question 1

How long does it take to lose 10 kg?

Accepted Answer

It depends on your starting weight, because the evidence-supported rate is 0.5-1% of body weight per week - this calculator sizes your deficit to that rate, between 250 and 750 calories per day. At about 0.45 kg (1 lb) per week, losing 10 kg takes roughly 22 weeks (about 5.5 months). A milder deficit takes longer but is more sustainable, while an aggressive deficit is faster but harder to maintain and may lead to muscle loss.

Question 2

What is a safe rate of weight loss?

Accepted Answer

The evidence supports losing 0.5-1% of your body weight per week - for most people that is a daily calorie deficit of roughly 250-750 calories. Losing weight faster than this often means you are losing muscle along with fat, and it is harder to sustain long-term. Slow, steady weight loss is more likely to stay off.

Question 3

How many calories should I cut to lose weight?

Accepted Answer

Size your deficit at 0.5-1% of your body weight per week - for most people that is roughly 250-750 calories per day below your Total Daily Energy Expenditure (TDEE), the calories you burn daily. This calculator never plans an intake below your estimated resting metabolic rate or the 1,200 calorie (women) / 1,500 calorie (men) guideline floor. The BMR line is not a physiological limit - but the estimate itself carries around 150 calories of error, and eating under it makes muscle loss and nutrient shortfalls more likely.

Question 4

Why does weight loss slow down over time?

Accepted Answer

As you lose weight, your body requires fewer calories to function (lower TDEE). This means the same calorie intake that created a deficit initially becomes closer to maintenance. This is called metabolic adaptation. To continue losing, you may need to slightly reduce calories or increase activity. Our calculator accounts for this by recalculating TDEE as your weight decreases.

Question 5

Is a 1000 calorie deficit safe?

Accepted Answer

For most people, no - a 1000 calorie deficit exceeds the evidence-supported rate of 0.5-1% of body weight per week and often costs muscle along with fat. This calculator caps the deficit at 750 calories per day, and lower for lighter bodies. A 500 calorie deficit is a sustainable starting point for most people. If you have significant weight to lose, consult a healthcare provider about an appropriate deficit level.

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