How much fat can you pull from your fat stores for your energy needs?

(Katie the Quiche Scoffing Stick Ninja ) #1

Now that I am fat adapted and about to enter my 15th week, I am going to keep OMAD fasting 24 hours a day, but to keep my body guessing will play around with ADF and 48 hour fasts too.

I’ve recalculated my macros with a 22% deficit based on my current stats ;

Sedentary
1241 calories a day
81g fats
20g carbs (never eat that)
108 protein (calculated at 1.0 because I am going to start working out)

I have roughly 13-16lbs of body fat to lose

Should I try and meet my protein goal as much as possible without adding too much dietary fat?
How much of my energy can be drawn from my body fat stores?
I’m just wondering how much dietary fat to actually eat, or how much my body can provide.
Hope that makes sense lol.

I still need to do a lot more research into keto gains and if I need to change my diet further to assist with that.

Any help would be THUPER and mostly appreciated :slight_smile:

#2

Here is a post by Richard on how much fat you can pull from your stores based on weight/LBM

As to protein you will need to at least hit your minimum .

(karen) #3

If I’ve got it right, there is an actual formula for how much body fat a person can access / lose in a day.

Take the number of pounds of fat on your body, and multiply it by 31. That’s the number of body fat calories you can use / lose in a day (a pound of fat has 3500 calories).

So … if I weigh 160 pounds and I’m 25% body fat, that’s 40 * 31, or 1240, which is about 1/3 pound of fat. Plug in your own numbers to see what you get.

ETA: I’m not entirely sure this is the whole story, surely people running fasted marathons use more than this small amount of stored energy, but it’s the “formula” I found (1). (I’m guessing fat adaptation changes the game somewhat, but I have no idea how much.)

(1) Alpert SS, A limit on the energy transfer rate from the human fat store in hypophagia, Journal of Theoretical Biology. 7: 233(1) 1-13. 2004. University of New Mexico.

#4

I’m halfway through the Dr. Fung 3KD podcast and he was just about to speak on that before I shut it off. If you cant listen to the whole thing, listen around the 40 min mark. Basically he isn’t convinced that this limit idea is truth.

Podcast is from Aug 2016 though. So if his ideas have changed I’m not sure.

I’m starting to read his fasting book. It was only $10 on kindle.

#5

Also, holy crap I was dying. :rofl::rofl:

Dr. Fung dropping the f bomb like nobody’s buisness

(Empress of the Unexpected) #6

Yeah, what’s up with that? Makes him look really unprofessional. He might have good things to say, but why the necessity for profanity?

(Empress of the Unexpected) #7

Katie, you are overthinking this. I am at maintenance at 16 weeks. Your body needs nourishment. Thirteen pounds is nothing. Don’t put your body at risk for that. TMAD is sufficient.

(Katie the Quiche Scoffing Stick Ninja ) #8

My maths is shit so I hope I get this right

155 pounds total with 30% body fat = 46 pounds * 31 = 1426

I am not sure what this is supposed to tell me, this means I can supplement ALL of my fat via my stored body fat?

(Katie the Quiche Scoffing Stick Ninja ) #9

Thanks for the link :slight_smile:

(karen) #10

… it really just means that’s the absolute maximum amount of body fat your body can access in a day. “How much of my energy can be drawn from my fat stores” - yes, if you’re actually burning 1240, theoretically all of it. If you fast, you should be able to access all the calories you need from your fat, and not start breaking down muscle - which could happen if your fat-burning limit can’t keep up with your calorie needs.

This number doesn’t really tell you much about what you need to eat to cover your exercising needs, keep from going into a metabolic slowdown, promote fat loss or stay in ketosis, sorry, it’s just one piece of info. Good luck, and congrats on your success so far!

(Katie the Quiche Scoffing Stick Ninja ) #11

Thanks for explaining it, I understand it now!

#12

I found I liked him all the more for it, but I swear like a sailor.

I find the stored fat access to be an interesting idea, but I agree there are too many variables to really do much with it. Except once you get past a certain low body fat % you are going to want to eat some calories.

(bulkbiker) #13

Possibly because he is quite passionate about what he has to say… also he’s human…
Best not to judge the message by how it is delivered?

#14

@kib, @anon54735292
I would take the Alpert calculation with a grain of salt. It’s based on starvation - not fasting - and on folks who are not fat-adapted. This is not to say that there’s no limit to how much fat we can access during a fast; maybe there is, but it’s probably highly variable. I wouldn’t use that study as a basis if you’re fat-adapted and fasting rather calorie-restricting (unless I’m getting my studies mixed up, this is on long-term calorie restriction, which as we all know is a disaster for energy and metabolism).
Based on the calculation I would be a wreck on a water fast, but I’ve often done hot yoga classes on top of a full day of work with no problems on days 3 or 4 of an EF.

#15

Here’s the starvation portion of the experiment that is the basis for Alpert’s calculation:

Semi-Starvation Period (24 weeks): during the 6-month semi-starvation period, each subject’s dietary intake was cut to approximately 1,560 kilocalories per day. Their meals were composed of foods that were expected to typify the diets of people in Europe during the latter stages of the war: potatoes, rutabagas, turnips, bread and macaroni._

I’d be very curious to see a similar calculation based on fat-adapted fasters, but I’m not holding my breath on that study :slight_smile:

(Raj Seth) #16

Do not use the caloric deficit model. Use the maintain model. Then, eat when hungry, eat till full. Don’t eat when not hungry…
The lower insulin level will allow your body to reset its set point and the body will down regulate the fat stores to where it wants. A few IF, ADF etc is what you need. But eat what your body wants (minus carbs)

(Katie the Quiche Scoffing Stick Ninja ) #17

I was under the impression that once adapted to switch to a deficit?
I cant even meet either calories on Omad whether its 1200 or 1500.
I want to start working out again, I am just trying to work out how to maximize the last of my weightloss so I can start getting ripped :joy:

(Katie the Quiche Scoffing Stick Ninja ) #18

Thanks for explaining. I’ve never heard of this study so its interesting.

#19

There is a fair bit on youtube about whether you should cut or bulk depending on where you are in terms of bodyfat% & how long you’ve been training. You’ll have to trawl through some dudebros but you might find a trainer you like. Are you basing your 30% bodyfat on a Dexa or is it more of a guess - I ask because having seen your pictures (well done by the way :smile: ) I’d have pegged you a bit lower.

(Katie the Quiche Scoffing Stick Ninja ) #20

I have an excel document that I input my measurements of weight, chest, waist, thighs, calves, hips, wrist and forearm and it calculates my estimated lean body weight, body fat weight, percentage and BMI

So when I input my current weight at 70.5 and I get ;

55.68 lean body weight
14.82 estimated body fat
21% estimated body fat percentage and
24.98 estimated BMI