How much fat can I lose in one week?

by Brad Pilon

I’m not sure if you already knew this, but next weekend I’m entering my first power lifting contest in well over a decade.

I’m going to try to lose a couple pounds in order to ‘sneak’ in to a lower weight class.

When I told a friend I was going to try and drop 5 pounds she replied:

“FIVE pounds of FAT? Can you even do that in a week??”

Now truth be told, I’m not planning on dropping 5 pounds of fat…I’m just going to do the contest fasted.

But it raises a good question…could I drop 5 pounds of pure body fat in a week if I had to?

Time for some rough math.

I’ve got about 150-155 pounds of lean mass…that puts my resting metabolic rate at roughly 1,800 Calories.

Add in my AVERAGE daily exercise and movement and I might get to 2,500 Calories being burned in a day…if I’m lucky.

Now…everybody likes to talk about it taking a 3,500 calorie deficit to burn a pound of fat, but unfortunately it’s a little more complicated then this. You see, it’s not until the later stages of fasting where you are burning mostly fat…for the first couple hours your burning mostly the calories from your food. For the next couple hours you would be burning a nice mix of sugar and fat. In fact, it’s not until the later stages of a 24 hour fast where you are burning close to 100% body fat…

So in reality you’d probably have to burn a very conservative 4,000 calories (realistically it’s probably more than this, and the number probably varies from day to day.) TOTAL in order for 3,500 of those calories to have come from Body Fat.

So I would need to burn at least an extra 1,500 Calories in order to burn a total of 4,000 Calories per day.

Under this logic, to burn 1 pound of fat in a day, I would need to be fasting, run around 10 miles, then get in a pretty intense 1-2 hour weight training session in.

Now, to lose 5 pounds of body fat in a week, It wouldn’t be this much work every day (I could probably cut the run down to 5 miles)..but it would take 7 days of fasting (which I’ll probably never do)…and running 5 miles per day for 7 days straight (again..probably not going to do this in my lifetime) and a couple of weight training workouts.

So, the chances of me losing 5 pounds of Actual body fat in a week…slim to none.

I can lose 5 pounds of weight no problem…heck I’ve done that in one 24 hour fast, but 5 pounds of pure body fat…this takes time and effort….

Now my math may be of in some places, but the point remains: 4-5 weeks would be a much more realistic goal.

So bottom line, losing weight is easier than losing fat…so don’t ever get discouraged on the days when the scale doesn’t really move after a fast…even a half pound of fat is an impressive feat…

Another point…even if it’s not all fat..the weight you lose is weight you didn’t need to be carrying..whether it’s inflammation, food weight or the mysterious..’other’ it’s stuff you really didn’t need.
Just trying to help you keep it all in perspective,


PS – In case your interested, I have a big sale going on over at To celebrate the launch of the Eat Stop Eat audio

book, I’m giving it away for F*R*EE to anyone who purchases the original Eat Stop Eat book over these next three days.
If your interested in Eat Stop Eat, now’s a great time to get it…That’s two book for the price of one!
Get Eat Stop Eat & the Eat Stop Eat Audio Book now ==>


Robert June 1, 2010 at 6:05 pm

Ha. Enjoy the cut. I have a powerlifting meet in less than 2 weeks and brought my weight to 2 lbs above the cut off for the weight class I want. I’ll drop that easy overnight from dehydration. I prefer to be within that range for my weight class. I don’t like the idea of sudden huge drops in weight from dehydration like many powerlifters do. Because of all the playing around with weight that they do for the weight classes, they know all about the differences between muscle mass, fat mass, and water weight as they effect that general mass known as scale weight. Other folk, though, I find think like your friend. They only think of the scale as measuring fat.

Brad Pilon June 1, 2010 at 8:12 pm

I’d be curious how a meet would go if they were divided by height instead of weight….or some measure of height and weight.

Thomas June 2, 2010 at 3:35 pm

Great post Brad! The way you explained it is exactly what I have been telling my wife. If she looks at that scale one more time and tells me she lost 3lbs of fat only to gain it back the next day(LOL. People dont get it! How much food, water, etc. you took in or didnt take in makes a big difference in your weight loss or gain, but could not have affected fat at all.

Sopa Quema Grasa November 4, 2010 at 8:52 am

Gracias por los comentarios. Este blog es genial, suerte!

Previous post:

Next post: