Will eating 1/3 of normal calories throw me out of ketosis?

(Alex) #1

Instead of the usual fast, I’ve decided to do a daily 18/6 but reducing my caloric intake to 1/3 or less of my recommended intake. I am keeping 75% fat, 20% protein, 5% carbs. Lot’s of boiled eggs basically with butter and olive oil eaten and drank straight up, and a tomato or cucumber here and there. Will that throw me out of ketosis?

(Joey) #2

Frankly, it wouldn’t matter much whether you’re in ketosis (i.e., burning fat rather than carbs), as your metabolism will eventually unwind on this sustained regimen … and you’ll have a hard time burning anything.

Starvation remains perhaps the bleakest way of becoming unhealthy.

Just my $0.02.

(Alex) #3

I see your point. I thought I read somewhere that decreasing caloric intake, living a bit hungry actually helps with longevity. In any case, If I do this, I would do it for a month to see the result, but I want to stay in ketosis.


Even eating nothing is keto, it’s more like about carbs but why those percentages? I would avoid eating low-protein… Proper fast is different a bit but if you eat, get your protein.
When I eat a lot, I can pull off 30% protein but eating a third, I would need… 80% protein? (Just theoretically as I can’t starve myself.) Keeping the percentages seem pretty crazy to me.

But if it’s a short interesting experiment and you know what you are doing, I have nothing against it. I had some crazy but not dangerous experiments myself. Very short ones. 1 day long ones, usually.


A third isn’t a bit. It’s severe starvation and I doubt it could be healthy.

(Joey) #6

I guess it matters what “a bit hungry” means. Cutting out 2/3rd of your “recommended” caloric intake sounds like a lot more than a bit :wink:

We fast everytime we go to sleep. And many of us routinely skip a morning meal, going for TMAD (two-meals-a-day), myself included. I’m a fan of thoughtful eating. But frankly, I can’t remember the last time in 3-4 years that I felt what I would describe as hunger once I became fat-adapted.

What you described above - seemingly on an open-ended basis - sounds like a sure way to wind your metabolism down. You haven’t stated what your goals are, but it is highly unlikely that this is what you are trying to accomplish.

Perhaps clarification might help invite a range of views from others. :vulcan_salute:


A month? Ouch. It may be short enough not to damage your metabolism permanently (I know nothing about that but it seems that can happen to people undereating for a very long time) but doping it temporarily isn’t good either. How could it be healthy to have a not properly functioning body? And it can’t function properly with very little. Okay, this is for people without huge fat reserves where it’s impossible to get the rest of the needed calories from body fat. But it’s the case for most of us. Even with lots of fat, it sounds probably dangerous and unpleasant (the latter is very individual though)… Maybe not in every case but in many…?

Did you try anything like this? Why do you think you are able to do such a thing? I am pretty sure many of us couldn’t do it, thankfully.
And I wouldn’t think anyone not SUPER sure having an immunity to eating disorders should try this. But even so, why? Why this super extreme thing? It won’t help with longevity, this is just way too hardcore.

And calories are one thing. But how do you get your nutrients? You will lose muscle due to little protein but there are lots of micronutrients hard to get from a lot of fat and a tiny bit of protein source.

(Doug) #8

You’ll be burning more of your own stored fat - ketosis undiminished, perhaps even boosted some.

(Alex) #9

Main reason for doing it, If I do it, is to lose some extra weight. I no longer feel hunger. Since been on keto, hunger has disappeared, I have to remember to eat. But many of you have valid points, especially about my metabolism. Maybe cutting the calric intake in half and trying it for a week is the wiser approach.

(Joey) #10

I’ll respectfully disagree with those who think this is a good idea - especially to lose weight. When your metabolism shuts down out of self-preservation, you will not burn more body fat. You will burn less.

Many have reported “stalling” in weight loss on calorie restriction, only to continue losing when they increase their dietary intake to a healthier level (still restricting carbs, of course).

It’s not uncommon to lose hunger sensations after a while on carb-restriction. This is especially in stark comparison to the compelling urge to eat every 2-3 hours when eating high carb. The contrast is striking to most of us at first.

And don’t force feed yourself when you’re truly not hungry. Perhaps consider trying one meal a day - well rounded and sufficient in quantity - if that’s comfortable. Or simply further narrow your feeding window.

But if you starve your body it will kick into survival mode (i.e., low gear) by turning down the furnace until you will feel lethargic, fatigued, headachy, etc.

(Chuck) #11

I have learned the hard way that calorie restriction will destroy my metabolism. I lived over 10 years with restricted calorie intake and it literally destroyed my metabolism and it wasn’t until I read about keto, low carb and fasting and started intermittent fasting with low carb and slowly increasing my calorie intake that my body started healing itself. I now fast between 18 and 23 hours each day and feast for a narrow window of eating time that I am losing fat, slimming down, and losing only a minimum amount of weight. I have so much more energy, my skin has greatly improved. My skin rashes and arthritis has disappeared, my digestive issues have gone my brain fog has gone and even my attitude has greatly improved. And to be honest I even enjoy what I eat so much more.
I don’t restrict myself in what I eat but I also don’t stuff myself, I fully understand what it means to be satisfied with the amount I eat without ever feeling hungry, or discomfort because I ate too much.



It’s literally just a sped up path to the calorie trap, when somebody says at 110yo that the reason they made it up there is that they starved themselves for the past couple decades then that can be almost credible, and I still wouldn’t do it.

(Bacon is a many-splendoured thing) #13

It’s not likely to throw you out of ketosis, since your carbohydrate intake will remain low, right? But restricting calories is the signal to the body that there is a famine going on. It will respond by slowing down the metabolic rate and putting non-essential processes, such as hair and nail growth, and the reproductive system, basically on hold.

If your goal is fat loss, this is not a good strategy, since the body will attempt to hold onto your fat store for as long as possible, in an attempt to get you safely through the famine. If you want to rev up your metabolism, eat more, not less.

(Bacon is a many-splendoured thing) #14

This appears to work on rats and Planaria spp., but human beings are neither rats nor flatworms. Rats also do just as well on a true low-carb diet (most of the so-called low-carb rat chow formulas are loaded with dextrose, so I don’t know how they can be called low-carb). But it is extremely difficult to get mammals into ketosis, except during the late stages of starvation. Human beings are the only exception to that, of which I am aware.

(Bacon is a many-splendoured thing) #15

Ron Rosedale gave a lecture several years ago, in which he advocated a protein-deficient diet in order to avoid activating mTOR and enhance longevity. However, as Benjamin Bikman points out, activating mTOR is a necessary part of tissue repair, so how are you going to live longer with decrepit tissues?

All things in balance: we don’t want autophagy to cannibalise our muscles any more than we want mTOR to hasten cell apoptosis. But a controlled amount of both is required.

(Alex) #16

Overall, I think it was a dumb idea, I’m not going to go through it. I guess after being on a ketogenic diet for this long, I wanted to shake things up a little. Not worth the risk to damaging my metabolism.

(Joey) #17

I’m relieved to hear you’ve ruled it out, for your sake. An excellent question though and, notwithstanding the barrage of replies received (:wink: ) the exchange may prove helpful to others coming along to this site in the future. :+1:

As is often said around here, it’s food for thought.

(Bacon is a many-splendoured thing) #18

It gives us food for thought, even as we give thought to food. :rofl::rofl::grin::grin::grin::grin::rofl::rofl:


It’s important to allow stalls in my opinion. Especially after a long loss period. If your loss stalls, it means your body is adjusting to it’s new weight and mopping up, re-distributing fat, firming skin and on and on. Watch your body instead of the scales. If you must, measure yourself. Notice how things shift. Your metabolism is recovering. The last thing you want is your body to think it’s in starvation times - it will store everything and use little to nothing. Bad news.

When I do want to get out of a lengthy stall, I tend to go OMAD and carnivore for that one daily meal. I eat as much at that meal as I want, and it can be quite a lot. It throws me right back into a loss pattern. But, that’s me. We are all different…

(KM) #20

Are you familiar with Dr Jason Fung? He does some extended fasting. His motto is basically feast, or fast. Pure fasting will definitely take your weight down, if you’re comfortable with that. Then you can eat normally on the days you do not fast. You might want to check out our member Gaff, who is doing longer fasts every week and then refeeding on weekends.

Apparently this does not slow your metabolism in the same way as continual calorie restriction, but should have the same result in terms of burning fat.