Is it possible to lose a pound in a day?

Yes, it is possible to lose a pound in one day through a combination of reducing calorie intake, increasing calorie burn through exercise, and some special techniques. However, losing a pound of body fat specifically requires a 3,500 calorie deficit, which would require more extreme measures. Most weight lost in one day is typically water weight or waste in the digestive tract, rather than pure fat.

How many calories to cut to lose a pound?

To lose one pound of body fat, you need to have a calorie deficit of approximately 3,500 calories. This is because one pound of fat contains about 3,500 calories. So to lose a pound in one day, you would need to cut 3,500 calories from your regular intake in that day.

Cutting so many calories in one day would be extremely difficult and likely unhealthy. To put this number into context:

  • The recommended calorie intake for an average woman is around 2,000 calories per day.
  • For an average man, it’s around 2,500 calories per day.

Cutting 3,500 calories would involve completely fasting for the day. Even with extreme calorie restriction, it would be incredibly challenging for most people to create a 3,500 calorie deficit in just one day.

How much exercise to burn 3,500 calories?

Instead of cutting calories, you could try to burn 3,500 extra calories through exercise. However, this would also be extremely challenging to do in one day. Some estimates for how long certain activities would need to be performed to burn 3,500 calories include:

  • Running – Around 5 hours of running at a 10 min/mile pace
  • Swimming – Almost 8 hours of swimming laps
  • Weight Lifting – Around 12 hours continuously lifting weights

As you can see, burning an extra 3,500 calories through exercise alone in one day would require an incredible amount of physical activity, far more than most people could perform in one day. And this estimated exercise does not account for the calories you would need just for basic functioning during that time.

Healthier approaches to losing a pound in a day

Since extremely restricting calories or over-exercising is unrealistic and unhealthy, here are some alternative ways to approach losing a pound in one day:

Reduce calorie intake moderately

Aim for a 500-1,000 calorie reduction for the day. This is a more moderate deficit that can produce weight loss results over time without being too extreme.

Increase exercise, but not to extremes

Add some extra exercise like a 30-60 minute cardio workout, but don’t overdo it to the point of exhaustion or starvation.

Lower carbohydrate intake

Reducing carbs causes the body to shed excess water associated with storing carbs/glycogen in muscles and the liver. This can result in noticeable scale weight fluctuations.

Increase water intake

Drinking extra water can help flush out excess sodium, resulting in lower water retention.

Reduce sodium intake

Too much sodium causes the body to retain water, so cutting sodium lower water weight.

Try intermittent fasting

Fasting from 8pm until noon the next day, for example, can help create a calorie deficit.

Focus on nutrient dense, low calorie foods

Eat plenty of fruits, vegetables, lean proteins, whole grains. These promote fullness while being low in calories.

Get plenty of sleep

Being well rested can reduce cravings and stress hormones that lead to water retention.

Is it possible to lose a pound of fat in a day?

While it is possible to lose a pound on the scale in one day using the techniques above, it is very unlikely that an entire pound lost is pure body fat.

Losing body fat requires being in a calorie deficit over an extended period. The body typically does not burn a significant amount of actual fat in one day.

Here is a more realistic breakdown of what may account for weight loss in one day:

Water weight – 0.5-1 pound loss

Through lower sodium intake, reducing carbs, increased water intake and exercise, you can shed water retained in the body. This accounts for a substantial amount of rapid weight loss.

Food waste – 0.2-0.5 pound loss

Through regular bowel movements, you can eliminate waste and undigested food in your digestive tract. This does not represent fat loss.

Glycogen loss – 0.2-0.5 pound

Lowering carb intake causes the body to burn through glycogen stores in the muscles and liver. The water attached to glycogen is then lost as well.

Fat loss – Less than 0.5 pound

Only a very small amount is likely actual fat loss. The body resists giving up fat stores quickly. Even in a 1,000+ calorie deficit, not more than about 0.5 pound of fat would likely be metabolized in one day.

Can you maintain losing a pound a day?

It is not realistic or healthy to try losing a pound a day over an extended time. The techniques that cause rapid weight loss in one day cannot be sustained long-term.

Attempting to lose a pound a day could be dangerous over weeks or months. Side effects could include:

  • Fatigue and dizziness from calorie restriction
  • Dehydration from fluid loss
  • Nutrient deficiencies
  • Muscle loss
  • Gallstones
  • Irregular heartbeat
  • Electrolyte imbalances

A weight loss of just 1-2 pounds per week is recommended for most people. This promotes safe, steady fat loss over time. Shooting for more than that is risky and unsustainable.

Should you try to lose a pound a day?

Trying to lose a pound a day by severely restricting calories or over-exercising can be dangerous. It can also set unrealistic expectations that lead to frustration when actual fat loss does not happen that quickly.

However, using some of the healthier techniques described above to lose around a pound in one day from time to time is not necessarily bad – as long as it is not taken too far. Just keep realistic expectations and practice moderation.

A healthy mindset for weight loss

The scale is fickle. Temporary fluctuations happen all the time that can make it look like you gained or lost weight rapidly. True fat loss occurs gradually over weeks and months. A healthy mindset looks past day-to-day fluctuations.

Focus less on the scale and more on building healthy habits you can practice long-term like:

  • Eating more vegetables, fruits and lean proteins
  • Drinking more water
  • Exercising for 30-60 minutes several times per week
  • Managing stress
  • Getting enough sleep

These habits will promote fat loss over time without extreme deprivation. With patience and persistence, the pounds will come off in a healthy, sustainable way.


It is possible to temporarily lose around one pound in a single day through extreme calorie restriction, excess exercise, lowering carbs and sodium, and other rapid weight loss techniques. However, this is mostly water weight and food waste rather than actual body fat.

True fat loss occurs over weeks and months in a moderate calorie deficit of 500-1,000 calories per day. Losing more than about 1-2 pounds per week risks side effects and is unsustainable long-term. Patience, persistence and building healthy habits lead to successful weight loss over time.

Leave a Comment