Predicting Weight after Fat Loss

Is there a way of predicting / calculating potential bw at different bodyfat percentages as we lose weight. Are there formulas available to help with this? I was looking at CT latest article . He had some height and weights for naturals . But I think these were upper limits for most people.

I targeting 75 kg at 5 6 or perhaps 80kg , roughly 175 lb.

Any help is greatly appreciated.

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You have been making topics about cutting since 2018. How about you just finally start doing it and you wont have to predict anything because you will just see.


Yes and no. Plenty of tools and whatnot to tell you what you could be when you reach xx% BF, but it relies on accurate BF% readings - which are rarely obtained (use Dexa scan or water displacement if really needed, but no one really needs to know BF%).

175lb and 5’6 would look fine, but it really depends on what that weight entails. I’ve weighed 220 with mostly muscle and also 220 with mostly fat… the scale said the same thing but mirror told a different story.

RE the Thibbs article, this is pretty accurate. FFMI is decent, but usually much worse in accuracy for higher BF% individuals (reads a much better number than is true). Again, FFMI relies on accurate BF% readings - which you would no longer need FFMI if you knew your true BF%. It’s an incredibly circular process.

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Enjoy. You could flip the inputs/outputs or use a data table in Excel to generate some quick estimates of what you want. Using mean of these equations is pretty decent (within a few% of reference methods). At least as good as the crappy Renpho scale everyone seems to have now.

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Many thanks. It is just for a rough idea really.

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I can understand this statement if one is trying to use FFMI as some sort of strange proxy for BF. But that isn’t what it is good for. It’s utility is (given an accurate BF measurement) to characterize the amount of lean muscle an individual is carrying per unit height. Very decent tool to assess if someone is using anabolics.

Decent papers here if anyone wants more info:

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what’s ffmi stand for in this context . Mas index?

Sure, 4 inputs but you can use the equations with only waist, weight, and height for some guess work.

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See above.

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I am with @hankthetank89 on this. If you have been talking about losing body fat since 2018, I would think we should be seeing success stories. You wouldn’t fall into the loop category “when all is said and done, far more was said than done,” would you?

Paralysis by analysis. Do it.

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Thanks I have lost 14 pound since I started but have a long way to go.

My suggestion is to train and eat with the aim of liking what you see in the mirror. That is the goal that is most meaningful at this time in your quest, IMO.

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Yes, math is the ticket.

If you keep your muscle while losing fat, then take your BW, and subtract your lean mass. The result is how much fat mass you have. Divide total weight by the fat mass, and that gets you BF%.

You can make a table with these equations, for what weight you will be at different BF percentages.

Of course, if you lose muscle, you will have to account for that in the math.

You will also have to account for water depletion when cutting down. That water comes back when you stop cutting, so you will want to go a bit lower on BW to ensure you hit the BF% if that’s important.

Or just go by what you are looking like.

Thanks Ben. How do U know your lean mass?

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If you have a good idea of you body fat percent, you would take that percent in decimal form and subtract it from 1, then multiply by your body weight.

So I’ll use myself. I am right around 200 lbs, and right around 15% body fat. 1-0.15=0.85. 0.85X200=170. 170 lbs would be my lean mass.

So if I went to 190 lbs (after regaining water weight, and assuming I kept my muscle), I could find my lean mass percent as (170/190)X100=89.5% (multiply by 100 to get a percentage). Then my body fat percent would be (1-0.895)X100=10.5%.

The calculator @readalot linked is actually pretty good (better IME than the scales with hand grip things) for getting body fat percent. You need weight, height, circumference of the neck and belly at the navel. Be honest with your measurements (don’t suck it in haha).

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Or simple waist to height ratio as we covered in another thread. No way to cheat that method if you are being honest with yourself.

All of the many methods of calculating percent body fat provide “entertainment” and very little value. The only value is knowing whether you are gaining or losing body fat. My preferred method is the skin fold test. And not for its percent body fat calculation, but for whether the skin fold millimeters are increasing or decreasing.

I maintain that the mirror is the only body fat test that is necessary.

Please understand that I love mathematics and enjoy calculating things. All that stuff is entertaining. But is the mirror is the result you are looking to please.