Correct Protein intake and Fasting question

fasting
protein
#1

Hi.

I’m new to the forum so ‘hello’ everyone.

I’m just starting my Keto journey but have been IF 18:6 on and off for a year or so.

I was watching a video by Pradip Jamnadas last night and he suggests protein should be at 0.35g per lb (0.78g per kg). At 45kg (yes, I’m super petite at 5ft) this would put my daily protein intake at 35g as opposed to the 84g which Carb Manager has set me at. This is a huge difference so which is right?

Another question I have relates to fasting. My body fat sits at 21% - what are the chances of me being able to do a three day fast? I can do 24 hours no problem but I did a 36 hour fast a month ago and woke up feeling pretty rubbish with low blood sugar at 3.4 mmol/L. Felt a bit dizzy and spaced out and ended up breaking my fast. It may have been down to improper sodium intake or a poor meal prior. Obviously I don’t want to fast for weight loss but the the many other benefits. My morning blood sugars often sit at 4.0 mmol/L and rise to around 4.7 mmol/L by midday.

Any insights on either of these?

(KM) #2

Welcome! I’m about the same height you are, I understand the frustration of dealing with markers designed for people of a very different size.

Technically 21% shouldn’t make 3 day fasting impossible. You’ve probably got 10 lbs to play with safely. I’d say anything over a week might become borderline dangerous. However, are you sure about that percentage? I know everyone is different, but when I was in college and weight training, at 110 I was only about 8% body fat.

I am nowhere near 100 lb at this point, but when I dieted 10 years ago I got close. I don’t know my fat percentage then, but I started to feel… fragile? Like for the first time in my life I really felt petite and delicate and not exactly solid. For me, that weight was really too low for fasting - or much of anything else, I overdid it. How did you feel, starting this fast?

#3

Thanks for your reply. Well, I’ve used our home scales which always give me this reading (or very very close to it) and a couple of years ago I was getting a similar reading on scales at the gym. I hold my fat around my middle. I have a 28" waist and I’d like to see that reduced if I can, ideally without losing any weight. Being tiny adds a whole other dimension to diet and fasting which is rarely addressed online where most information is about weight loss. I don’t feel fragile but I guess it’s because I’ve always hovered around the 45kg mark apart from when I was pregnant. When I weight train I feel strong but I never seem to gain significant muscle. I’m 51 so I guess there’s increasing age to blame for that.

Starting the 36 hour fast I felt fine. I was hoping to get to 48 hours but woke up at 3.00am feeling rubbish, panicked and stopped.

8% is very athletic. How did you get this low? Are you female?

(KM) #4

Yes, I’m female, 60. I was very athletic as a young person and tended to put on muscle versus fat, sadly no longer the case. Interesting, maybe it’s this season? I also started a supposed 3-day fast last Monday, and felt rubbish, stopped early. For me, it was probably caffeine. Usually in preparation for a longer fast I taper off my caffeine. This time I didn’t, and also started with a 24-hour dry fast experiment which meant I couldn’t even take the caffeine pill. Won’t be doing that again!

Interested to see what other people have to say, but it sounds like this is just a one-off for you, If this is your natural weight and you felt fine going in. Did you keep your sodium, potassium, magnesium up? Again due to the dry fasting experiment I couldn’t at first, that might have been the problem for me.

#5

Fasting: there are formulas about ability to fast and available excess fat but it’s just not that simple. Someone with 21% fat, even a female who has less extra fat may be able to fast for 3 days, surely many such people exist - but many others can’t do that without feeling bad. Do it if you feel okay, don’t if it feels a torture.
I am fat (barely, in my own opinion) and still don’t seem to be able to fast a single day. Something I easily did on higher-carb, oh well. Theoretically I can do it. I wouldn’t suffer horribly but it would have been so uncomfortable I just can’t do it by my own will without a really good reason. But I am a hedonist who loves eating a lot so there is that. But with the same fat reserves fasting was easier before.

For protein, I am among the very many people who consider 1-2g/kg for LBM the right range. I try and fail to stay there, I typically have 2.2-3g/kg days while I really try to minimize it. I personally need 130g protein a day to avoid being hungry at night (still before bed, I sleep through the night). I track a lot and this number is very noticeable. My body surely knows what it does and want and anyway, I am a hedonist so I give it this amount and try not to give it way more but sometimes I eat 220g, it’s unavoidable… But I feel good and it’s not so very excessive for an occasional day so it’s okay-ish. I do try to do it better. Eating higher fat AND focusing on lower protein helps a tad but just because I eat 250g fat, I easily can do that 220g protein too and I very rarely can go below my 130.

Maybe too much information about me but maybe it reassures people that some people need to go way higher and it’s still okay…? :wink:

Extremely low protein (like that 35g…) seems insane even if one can do it, to me, from various angles. At that point I would need to avoid not only basically all animal food but most of the plants too as they are too protein rich. It can’t be right. And it would be eating basically just fat. With a tiny little protein in the sea of fat. Sounds very, very wrong to me, again and this type of eating would make me nauseous and not only me I suppose. Yeah, on normal keto a huge volume of very low-carb vegetable could help… Or not… On carnivore, 35g protein would be something torturous… And my body favors being super close to carnivore. And my protein need isn’t any higher on that woe.

#6

As far as I know, a woman never should go even near 8%. This percentage is rarely sustainable even for males.
Surely there are some individual differences but 8% is super low for a woman. I think 14% is the lowest that is still okay…? Maybe going lower for certain reasons, competition or something…?

#7

One still can gain muscle then as long as one isn’t already muscular at that point. You probably do something wrong. I did the same, I lift since years, half-assed, with breaks, not always using the right exercises… Now I take things more seriously, watched a lot of videos and my weights started to get bigger at a way higher speed than usual. Of course, to gain muscle you need lots of protein and enough calories as well, at least I did that right but as my workouts weren’t good enough, my performance barely improved despite being still a begginer. A young man with good genetics may pull it off even when they do it not so right but I needed to do things right.

(You've tried everything else; why not try bacon?) #8

Our recommendation here is based on that of Dr. Stephen Phinney, the researcher who coined the phrase “nutritional ketosis,” and it is 1.0-1.5 g/kg of lean mass/day. In U.S. measures, that would be 2.2-3.3 g/lb. Some experts even recommend going as high as 2.0 g/kg, or 4.4 g/lb.

And remember that beef is 1/4 protein, so to get 100 g of protein, you would eat 400 g/14 oz. of meat.

I’m sorry you’re having trouble fasting. At this stage in your keto journey, however, we don’t recommend it. Your body is still re-adapting to using fatty-acid metabolism instead of glucose metabolism, so give it a rest for six to eight weeks before attempting to fast. The easiest way to get into fasting is once you start skipping meals by accident because you’re simply not hungry. At that point it might be much easier.

And yes, there is a limit to how much we can get daily out of our fat tissue, so fasting might still be a problem, since you are nicely lean. Or it might not. If you are interested in the actual numbers, Richard Morris did them and posted the result in the Show Me the Science forum. But thin people who want to fast can take a certain amount of fat during their fast and still gain the benefits. Do a forum search on “fat fast.”

(KM) #9

I was in training, yes, but this also just seems to be the way I was made. Back then it felt fabulous to be so strong and have no extra fat on my body. Over the years I have gotten to that 8-10% point variously with weight training, bicycling, running, aerobics, and Pilates. I wouldn’t recommend it as a set point for anyone else, I know it’s low. My thought in asking Vicky about it was that if she had just dieted her way down to her current weight, it was quite possible her fat percentage was significantly less. That doesn’t seem to be the case, so my thoughts still stand, at 21% I think she should be fine.

(Robin) #10

Welcome Vicky! Glad you found us! I have never attempted a fast, other than my one meal a day. But you will soon hear from lots of folks who are pros at fasting and it’s part of their routine.
I am adding the word FASTING to your title, to catch attention.

(KM) #11

How do you calculate what your lean mass is?

#12

the bodyfat % may also have inaccuracies depending on the type of measurement used as well. the only times i ever hit single-digit bf % was twice in my life – once when i was a professional athlete competing on the Olympic level, and that was measured with DEXA. and the other time was when i started carnivore and obsessed with losing the fat i put on over the years, but that was measured by my physician with a caliper. even though i was very lean during the latter situation, it is visibly obvious from photo comparison that my bf % was nowhere near what it was during the former period. so probably because the calipers just measure the skin to estimate the fat, and not really the fat itself.

(KM) #13

I was once measured at 5% with calipers, I don’t trust them. All depends on where on your body you store your fat, I think.

(You've tried everything else; why not try bacon?) #14

That’s an excellent question, with no good answer.

The most accurate measure of lean versus fat mass is done with calipers. It’s tricky and requires a highly-trained medical technician to get it right. A high-tech method is a DEXA (dual X-ray absorptiometry) scan, which is fairly accurate but can be thrown off if you are over- or under-hydrated. A lower-tech method would be a bio-impedance scale, and these are notoriously inaccurate. Personally, I just assume that my body fat is 30% of my total weight. That’s close enough for jazz.

As far as calculating your protein intake is concerned, however, it may not be all that helpful to know one’s lean mass to a high degree of precision. People’s need for protein is highly individual, and the protein recommendation is based on an average. So even if you get an idea of what your lean mass is and calculate how much protein to eat, you’ll still need to adjust to suit your body. If you find that no amount of fat assuages your hunger, then you probably need more protein, in order to be satisfied.

All mammals, including us, supposedly have an instinct for how much protein to eat (this is the basis of Raubenheimer and Simpson’s “protein-leverage” hypothesis), so go with what feels right.

(KM) #15

So the general definition of lean mass is total body weight - bone skin hair water toenails organs muscle and so on - minus fat?

(You've tried everything else; why not try bacon?) #16

That’s it. Lean mass is everything that is not fat mass.

(KM) #17

So if Vicky is a constipated Rastafarian, she probably needs an extra pound of protein a day. Lol. My basic thought process here was simply that the smaller you are, the more fiddly this gets. I much prefer the hypothesis that our bodies tell us what we need.

#18

I don’t think I went into it particularly well armed on the electrolyte front. I take 400mg magnesium daily but my salt intake definitely wouldn’t have been as high as suggested here.

(You've tried everything else; why not try bacon?) #19

Constipation can be caused by too little sodium in the diet. Remember that the normal rate of sodium excretion is higher, when insulin is low. We are so used to high-carb diets that we forget that elevated insulin causes sodium (and consequently water) to be retained. Getting enough fat also helps with constipation. But a caution here: on a ketogenic diet, bowel movements may be less frequent. That is not constipation, that is just the digestive system working as designed. Constipation means having to strain to move one’s bowel. The idea of “regularity” (i.e., moving one’s bowel daily) was created by laxative manufacturers sixty years ago, to sell product.

#21

Ha ha. This is properly made me giggle.