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Pounds of Fat In An Inch?

Random idea - could be full of shit. Maybe someone knows. Here’s the question: How many pounds are in an inch of fat when that inch of fat is around a person’s waist?

Would it even be possible to determine this? Since fat has the same density in everyone (and thus would take up the same amount of space per gram), it would seem so. But I really have no idea.

So let’s say a male had a waist of 45 inches. How many less pounds of fat would he have if his waist were 40 inches? (I am not asking how many pounds of fat a man would need to lose in order to lost 5 inches in his waist, as this is an analytically different question: After all, people don’t just lose fat in one place. So a person who loses 5 inches in his waist would have lost x-pounds of fat; but a person may need to lose x + y-pounds in order to lose 5 inches.)

Relatedly: Is it possible to determine what a person’s optimal waist size should be if you had the other measurements of a person? If a person had, say, x-inch wrist, y-inch ankles, etc?

Height would be another important factor in this.

[quote]CaliforniaLaw wrote:
Random idea - could be full of shit. Maybe someone knows. Here’s the question: How many pounds are in an inch of fat when that inch of fat is around a person’s waist?

Would it even be possible to determine this? Since fat has the same density in everyone (and thus would take up the same amount of space per gram), it would seem so. But I really have no idea.

So let’s say a male had a waist of 45 inches. How many less pounds of fat would he have if his waist were 40 inches? (I am not asking how many pounds of fat a man would need to lose in order to lost 5 inches in his waist, as this is an analytically different question: After all, people don’t just lose fat in one place. So a person who loses 5 inches in his waist would have lost x-pounds of fat; but a person may need to lose x + y-pounds in order to lose 5 inches.)

Relatedly: Is it possible to determine what a person’s optimal waist size should be if you had the other measurements of a person? If a person had, say, x-inch wrist, y-inch ankles, etc? [/quote]

I’m going to bet this differs wildly from person to person

pi x inches equals weight of fat

I think that’s going pretty difficult to determine with precision.

Like someone said, the height of the person will influence the result; the size of his internal organs; his general “shape”, etc.

You could abstract the problem to calculating volume of cylindrical torus minus the volume of the smaller one, the difference being the quantity of fat. But people aren’t circular, so the formula would be a far approximation at best.

Also, since you can’t spot reduce, even if you could calculate that someone with a 45 inch waist has 17 pounds of fat to lose to get to 40 inches, you’d have no way of knowing how many of those pounds could come from elsewhere.

I think the short answer will be: Too many variables for an accurate answer.

Just do what a lot of “professionals” do: bullshit your way to whatever answer you think is right.

Are you seeing purple and feeling hazy?.

[quote]CaliforniaLaw wrote:
Random idea - could be full of shit. Maybe someone knows. Here’s the question: How many pounds are in an inch of fat when that inch of fat is around a person’s waist?
[/quote]
The get an accurate answer you would need the total volume of fat and then you would multiply that by the mass density for fat. To get the volume of fat you would need to know the thickness and the surface area.

It is a simple calculation and will yield a close approximation:

Fat mass == width x surface area x density

The density of fat is .9 kg/L

1 liter is equal to 1000 cubic centimeters–10cm x 10cm x 10cm. The same volume of muscle is 1.06 kg.

If you lose 5 lbs of fat your waste will decrease approx 1 inch