Calculating protein from lean mass

#1

Just had a DEXA and I have 51.5 lean body mass
and fat mass of 32.8 kilos
If I am eating well, is 52 grams of protein about right for me?
And can any kind person tell me how many energy units my fat can provide me daily, if I fast?
I saw a calculator but I couldn’t manage to use it…arithmetically challenged! :slight_smile:

#2

Hi, that protein count sounds right. The formula is 0.6 to 1.0 g of lean body mass. OR 1.2g to 2.0 of a reference weight.

According to my understanding 52 g would be your upper limit of protein. Something like a 200 g steak, would that fill you up with veggies and stuff or do you reckon you’ll still be hungry?

As for the fat questions- Even the thinnest m person has got weeks or months supply, I’m not sure what you’re really asking. Calorie counting?

#3

52 grams of protein would be sufficient & is certainly a good place to start. As to available calories from fat, IIRC (can’t access it right now) Richard’s calculator allows approx 33 cals per day per pound of bodyfat - 1kg is 2.2 pounds or thereabouts.

#4

Thanks Alex99 and safi.
I couldn’t find the calculator!
Plus I am arithmetically very very challenged.
A 200 gm steak would fill me up most definitely. Even without veggies and I am adding butter to everything carnivore and olive oil too.

No not calorie counting but wondering how much energy my fat can generate in a day and therefore how much extra fat I need to be adding in.
Richard wrote it somewhere but
a) I am arithmetically challenged and
b) there was something else which escapes me now

I guess with 30kilos of available fat I have -a good energy source…just would like to have the numbers so I don’t sabotage my efforts. I’m trying very hard to get reversed out of the insulin resistance range having reversed out of the diabetes mellitis range!

Thanks again for the help. :slight_smile:

(Robert C) #5

Hi @anon13588705,

This is just on the protein calculation…

I would just like to restate what the 2KDs say here because I think you may be under calculating your protein.

First, their definition of lean body mass is not what a DEXA scan provides (although DEXA is technically providing true lean body mass). They needed an easy definition of lean body mass that did not involve DEXA, or a dunk tank or a bioelectrical impedance scale.

Instead, they mention lean body mass as your weight when you were young and slim (I think something like your best high school weight). So, for you, assuming your best high school weight is 15% body fat, that would be 60 kilograms.

They also recommend 1 to 1.5 grams per kilogram of lean body mass. I think the range is the low end being for more sedentary people and the higher end being for the more athletic. This puts you at 60 to 90 grams of protein per day.

#6

RobC, Thank you so much.
My healthy weight (way back) was 59 kilos, so, well calculated.

Thanks for your assistance, much appreciated.

(Robert C) #7

I am not a doctor or organic chemist so please take my (obviously incomplete) answer with a grain of salt.

Generally, day 5 or 7 of an extended fast for example, the answer is “just about all of them”. Deeper into a fast, almost all of your calories will come from fat because your fasting adaptations have kicked in by then (raising HGH for example to conserve muscle mass). So, if you are burning 2000 calories a day - you’ll burn up 2000 calories of fat.

The big issue seems to be around the first few days.

Here is my theory based on everything I know so far.

If you are fat-adapted on keto, most of the energy units you are burning - even at the beginning of the fast - are from body fat (which is good).

If you are coming from a non-fat-adapted state, I think you will feel like crap initially and that for the first couple of days your body might cannibalize muscle while clearing glycogen stores before being forced into fat-adaptation and good fasting adaptations.

Because of this, it seems like stringing together a bunch of 48 hour fasts with pizza, chips and soda is a bad idea but with strict keto between the same 48 hour fasts might be great (i.e. calorie is not a calorie - macro breakdown is the determining factor).

Again, not a doctor or anything but, this just generally seems to be the case based on what I have read here and elsewhere.

(mole person) #8

I just read a post of Richard’s where he said each pound of body fat could give up 31.5 calories/day.

You have 32.8 kg of fat so multiply that by 2.2 to give 72.16 lbs of body fat. Then multiply by the number of calories per day each pound of fat gives you:

72.16 x 31.5 = 2,273 calories per day accessible from your fat.

So you should have no trouble with fasts of reasonable length.

#9

Thank you both so much RobC for the very clear explanation and thank you Ilana_Rose for Richard’s calculation (and for kindly doing the arithmetic for me!
Much appreciate the replies and information.
I am fat adapted and carnivore for awhile now, so those numbers are helpful.
I saw Richard’s calculation somewhere awhile ago but at the time I didn’t have my stored fat number. I love it when the numbers support you to keep on! :slight_smile:

This is a different question but does anyone know what the % of body fat is optimal for heath? Or is that another one that varies from person to person and is age related?

#10

Below is a general guide but it will vary from person to person. I operate best at about 20-21% & am 45yrs old so according to the chart I’m low but I’m healthy & hormonally balanced so I think the lower end is where my body prefers to be.

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You may find this video by Amy Berger on the personal fat threshold theory interesting.

(mole person) #11

It varies a lot with how much muscle mass you have. It might be dangerous for an unmuscular woman to be sub 16% body fat but that’s just fine in an athlete. The reason for this is because the muscular woman with the same exact number of POUNDS of fat is FAR heavier because she has many more pounds of muscle. So even though the amount of fat she is carrying is identical her percentage of body fat is far lower.

Let me put this a different way:

Two women are both carrying 30 lbs of body fat. The first has very little muscle and a total body weight of 100 lbs, her % of body fat is 30%. The second woman is VERY muscular and has a total body weight of 187 lbs. The first woman is at 30% body fat and the second is at 16%, but they have identical fat stores to draw on for energy needs.

(Robert C) #12

Hi @anon13588705,

If you put an @ sign in front of people’s names (such as @RobC and @Ilana_Rose) then a notification is sent and people can read your “Thank you” (which is appreciated!).

Otherwise, it is just by accident that one finds a post mentioning themselves.

(Robert C) #13

Not sure but, I think this is someone’s idea of a theoretical maximum - if you treat it that way then you should reduce by some percentage depending on your lifestyle (good or bad sleep, stress levels, exercise levels, current injuries etc.).

I wonder if it is really a true theoretical maximum. Seems like keto 100 mile marathoners are going to pull more than that in their (very long) day of constant running - maybe there is an assumed maximum amount of exercise? Would be good to know the backstory to compare.

(mole person) #14

I’ve often wondered the same. I don’t entirely trust that the studies these values were derived from have the utility for which we are applying it. But this was the formula the OP was asking for so I provided the answer.

(mole person) #15

Actually the more I think about it the more I think it has got to be problematic. Take me as an example. I’m 110 lbs and less than 18% body fat. That means I have 20 lbs of fat of which only 31.5 calories can be taken out of each per day. So a total maximum of 630 calories a day?? After which I’m tapping protein structures for energy?? How can this be right? A two hour jog would have me past this. Further, I OMAD nearly every day. How am I not passing this maximum every single day between my meals?

Am I making some major logical error in my thinking?

(Robert C) #16

I don’t see a logical error - I didn’t believe the formula from day one - due to the ultra-marathon example.

That is why I think it is actually based on something more average - a mostly sedentary person (certainly not one that runs two hours a day). Maybe it is based only on someone at BMR all day (a baseline instead of a maximum). Your numbers look that way - if you really just laid around all day - maybe 630 calories of fat get burned off (if coincidentally fasting)?

Even being fat-adapted would come in to play here. A person that is not fat-adapted would have a calorie max extraction limit per pound of body fat that would be less than themselves if fat-adapted - simply because their hormones would not allow it.

(mole person) #17

I’m going to read the study this is based on tomorrow and see what sense I can make of this. I’ll link you if I find it.

#18

Thanks @RobC, Got it! :smile:

#19

In terms of my own metabolism, I am metabolically deranged due to years of misdirection medically with diabetes. I used to be a TOFI, was slim for most of my life til insulin resistance and didn’t get accurate info to stop becoming diabetic, despite or because of seeing the supposed top experts in the country (Oz)…tried hard, followed directions to the letter but was misdirected by dietitians in hospital metabolic units telling me to eat whole grains and fruit, low glycaemic index foods.
But I am on track with keto carnivore rigidly adhering to guidelines…doing strength training (2x weekly on Keiser machines with an exercise physiologist keeping me on track, rowing etc and with a 10 bicycle with full-on spurts of 10 secs once a minute. Hoping that may kick me back under the insulin resistance level along with rigid keto.
So the calculation for me is about trying to hit the maximum benefit of the fasting and the training.

I am caring for a very ill 93 yo recent above-knee amputation mum …which is incredibly motivating for me in trying to avoid future for-sure amputation for myself… currently taking time away from her care for exercise (with nurses standing in for me).
I am wanting to take any possible advantage from calculations I can, I am definitely an eat-to-live person. :blush:

#20

Thanks @Ilana_Rose, looking forward to this.

I am really rather confused about the numbers to use for myself. I will use cronometer to try and get my protein intake right.
Appreciated the Amy Berger personal fat threshold explanation. Will need to listen to it a few more times…got lost with it.

I am pretty massively stressed at present and it is affecting my concentration.