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Weight Loss/Corresponding BF Drop?

I have a quick question. What amount of weight loss (scale weight) would equate to a 1% drop in BF?

In other words, is it safe to assume that for every 3 lbs of fat or so you drop, you’ll drop 1 percentage point in BF? Or would you say it’s more than that - perhaps 5 lbs.

I’m just curious about the precise amount of fat loss that equates between scale weight and BF percentage.

Thanks in advance…

Depends on your body weight. If you weight 200 pounds then 1% body fat is 2 pounds. But if you loose 2 pounds of total body weight, it came from multiple sources: water, lean body mass or fat, certainly not all from body fat.

[quote]SkyNett wrote:
I have a quick question. What amount of weight loss (scale weight) would equate to a 1% drop in BF?

In other words, is it safe to assume that for every 3 lbs of fat or so you drop, you’ll drop 1 percentage point in BF? Or would you say it’s more than that - perhaps 5 lbs.

I’m just curious about the precise amount of fat loss that equates between scale weight and BF percentage.

Thanks in advance…[/quote]

It depends on how much you weigh. Do the math.

Get some calipers (pretty cheap, can be found for $10-15), and chart body fat % along with your weight. That way you’ll know if a drop of 5 lbs. in body weight is fat.

For example: you weight 200 lbs. with 20% b.f. Your body composition would be (200 x .20) = 40 lbs. of fat, (200-40) = 160 lbs. lean body mass (obviously not just muscle as this includes your skeletal structure, organs, etc). Then you drop 10 lbs., leading to a drop of b.f. to 17%. Your new body composition would be (190 x .17) = 32 lbs. of fat, (190 - 32) = 158 lbs. of lean body mass…meaning a loss of 8 lbs. of fat with a corresponding loss of 2 lbs. of lean body mass.

One final note: different diets lead to very different results when losing weight. If you drastically drop calories while increasing cardio you’ll probably find a huge loss in weight, but a good deal of that would be muscle. However, putting yourself in a slight caloric deficit (meaning you burn more calories than you consume over the course of a day), then slowly decreasing calories from there, would lead to slower fat loss but would also help in keeping your muscle mass intact.

Hope this helps!

[quote]dswithers wrote:
But if you loose 2 pounds of total body weight, it came from multiple sources: water, lean body mass or fat, certainly not all from body fat.[/quote]

Of course, but I’m saying if you’re making an effort to maximize fat loss and minimize LBM loss, then at 200 lbs, losing 2 lbs (if it’s mostly pure BF, with little to no loss of LBM) equates to 1 % loss of BF percentage, correct?

So if someone who weighed 200 lbs was at 20 % BF - then in order to get down to 10 %, they’d need to lose 20 lbs and weigh in around 180 (give or take a few lbs for water loss, etc.) - correct? Assuming this person had a solid physique built under that layer of BF…

Thanks for the replies.

I am an experienced BB who knows quite well exactly how to go about fat loss, but I’m lousy at math - so I was just curious what each 1 % decrease in BF percentage would equate to on the scale (assuming it’s almost purely fat loss).

Based on some of the formulas you’ve posted I’m getting a clearer picture. Thanks.

[quote]SkyNett wrote:
dswithers wrote:
But if you loose 2 pounds of total body weight, it came from multiple sources: water, lean body mass or fat, certainly not all from body fat.
[/quote]

One’s weight can flucuate 2-3 pounds a day depending on what you’ve eaten and how recently, how much water you’re holding, and how recently you’ve pooped, so a change of 2 pounds is not significant enough to draw any conclusion.

But if you weigh 200 pounds and over a few weeks you’ve dropped to 190, then you’ve lost 5 percent overall mass. Hopfully your BF is down 4 percent and LBM only 1 percent. If you were a somewhat chubby beginner and your program & diet are really dialed in, then maybe you lost 15 pounds of fat and added 5 pounds of muscle. Then your BF would have dropped 7.5 percent.