HI all. New here and I’ve been studying hard! I’m one week in and LOVING this “diet”. I am still unclear however on how the conventional wisdom of a lowered metabolic rate corrispondant with extreme caloric deficit is differ in ketosis. Why does the body not go into starvation when in ketosis? Or does it and I’m doing it wrong!!! My husband is taking note of the low calorie total of my fod intake (while eating intuitively) and very worried I’m harming myself. I want to explain this science to him, but I guess I’m still not clear on this exact point. Can anyone recommend any studis? Or have a clear answer on thus topic. I’m well versed on the how and what, but this issue of total calories is escaping my knowledge base. Cheers! (From calgary Canada btw)
Metabolism and calories in ketosis vs not. Help
The big difference between a calorie deficit as a sugar burner vs a fat burner is that when you are a fat burner, your body can tap the calorie reservoir that is your body fat.
Every pound of fat is about 3500 calories. You’re still getting the calories you require, but some of them are coming from your body fat instead of from food.
Nothing to worry about.
Really that simple hey? That’s the answer I gave my husband but he made me second guess myself. I love that he cares 
thanks for the validation.
Well, nothing is really THAT simple. But that is the gist of it.
There are signs that your body is ramping down your metabolism. You feel tired, you get cold when everyone around you is fine.
As long as you feel full of energy, you’re probably fine.
BUT…keep in mind that you don’t have access to 3500 calories per pound of body fat per day…max is about 31.5 calories per pound of body fat per day
it’s also unlikely after a week that you’re fat adapted and accessing body fat
don’t restrict food (or calories)
carb 20g (or whatever limit you set…20g or under is the standard recommendation)
protein 1-1.5g per kg of lean body mass
fat “the rest” which there is no magic number or formula…it’s just to keep you satisfied and keep your metabolism happy
it is really important to not eat too little…especially when starting out
(i’m assuming you’re eating very little if your husband is alarmed but that could be a bad assumption)
welcome 
tons of info and science here that you can show him to set his mind at ease
@Heidi_Barrett
I’ve read The Obesity Code and The Complete Guide to Fasting, and listened to all the 2KetoDudes podcasts. Yet I STILL struggled with a lifetime of being brainwashed with conventional wisdom regarding metabolism, calorie deficit, ketosis, why IF and fasting aren’t the same in the final outcome as a calorie deficit, etc etc.
It finally clicked for me when I read a simple statement from Dr Fung that cut thru my “programming”. It was this:
“The secret of success is NOT to limit some of the calories all the time (deficit dieting), which lowers metabolism. Rather, to limit ALL the calories SOME of the time… which is called Fasting.”
I finally saw the light, ha ha.
Also, I thought you’d enjoy Episode 19 of FastingTalk. During this one, starting about minute 13 thru 19, Megan Ramos talks about why OMAD (one meal a day) is not advantageous as a LONG term approach for weight loss; has other benefits after reaching wt loss goals. If done as a wt loss tool, without changing things up, can actually slow down metabolism.
I realize you didn’t mention OMAD, but I thought of it since you mentioned not eating that much. I also don’t feel that hungry now, and was tending to get into the habit of creating a daily calorie deficit. As Megan says in the podcast, doing that habitually will eventually slow down your BMR.
The idea is to lower insulin levels with the fasting, so the body CAN access the stored fat.
Hope the link helps. My best to you!
Absolutely. The goal is a caloric deficit over an extended period of time, not a caloric deficit every day.
I’ve been doing a feast/fast/feast cycle and it’s been working quite well for me.
Yes! That’s exactly what I’m learning to do now. I hope it works well for me, too.
This early in I don’t think you need to worry about fasting. This can lead to confusion when you are still trying to get used to keto. Like @mikki said above, it’s a little soon to know if you are fat adapted. When you are, your body will easily burn your fat stores for energy and you will spontaneously fast without thinking about it. Until you get to this point don’t try to restrict anything other than carbs. Keep an eye on your protein, but if it gets a little high from time to time that’s ok. As long as you can keep it in your range. Eat as much fat as it takes to get full and stay full. Now is the time to nourish your body with all the fat you used to restrict. BTW, I was keto for almost 2 years before I tried an extended fast. Let your body heal a little first.
Just to add to what’s also been said: is important that you not restrict calories at the beginning. This will actually stall your weight loss. If your body is not fat adapted and you restrict calories it will go into starvation mode. Eat fat to satiety and watch the magic happen. When you really got your first plateau, then you can evaluate and change things up. Welcome to keto!
3 of my favorite youtube videos explaining Keto.
Top 5 Keto Mistakes - Really goes into why it works. https://www.youtube.com/watch?v=mHu6bgx4JyM
10 reasons why you shouldn’t go Keto - Busts a lot of the myths about Keto. https://www.youtube.com/watch?v=9n01Q3Ije2w
Stop overcomplicating Keto - https://www.youtube.com/watch?v=jDcLkGYjgZs
Hopefully you get some value.
One of my favorite graphs that explains how our hormones affect what we do with fat is this one …
The X axis along the bottom is the amount of insulin we are making at any specific time of the day. When we eat carbs it goes to the right, when we fast or eat fat it goes to the left.
The Y axis is how much energy your body fat is releasing as a percentage. At the top your body fat is releasing energy as fast as it can (there is a maximum rate that that can happen, but let’s just think of it as 100%). Down the bottom your body fat is vacuuming up energy in your blood and storing it.
The blue bar is the normal range that healthy people eating a mixed diet swing through every day as we cycle from feast to fast, and that drives our insulin levels, and that determines when we release body fat or store it.
When we eat carbs, that raises glucose, which raises insulin which tells our body fat to store energy. When blood glucose goes low, so does insulin, and body fat kicks into gear giving us energy from storage.
When your insulin goes low (which is the primary mechanism of a ketogenic diet) you are running on body fat. You will have plenty of energy. It’ll be coming from a Krispy Kreme doughnut you ate a decade ago.
You are eating less because you have plenty of energy (because body fat is feeding you more of your daily requirements) so you are less hungry.
You are doing excellently - keep calm and keto on 
I’ve been keto and I’ve just started a feast/fast cycle, I recommend just becoming fat adapted, being keto for a while to get an idea of the things your body will tell you… My body tells me when to eat and when to fast… I listen and eat or don’t… It’s pretty simple… But it takes time, I’m about 8 months in full keto
Thank you so much everyone!
Thanks Rettakat for the links and recommendations.
Jimbo - that’s a great point about listening to how I feel. HOT is the answer!!! lol really hot. So that must be a good thing.
Richard - many thanks for answering so directly and the graph is very helpful.
Lucky for me, I think my body has adapted quite willingly. Although it’s only been a week, I feel that energy. I eat the right balance of macros when I get hungry and I’m down 8 lbs! Though if feels like more than that from the fit of my cloths.
This is some seriously cool S%^T.
Thanks again.
@mikki - Thanks. I’m not sure when I’ll be fully adapted, but I can say that so far I feel great and I’m eating naturally till i’m satisfied. Each meal is just going a long way! … You’re assumption is correct. I’m not eating a lot in one day. However, today I felt like I needed more and didn’t hold back. Just ate what my body wanted. I’ve also had to supplement electrolytes. My muscles really shouted at me when I needed magnesium! Also taking a B-complex.
sounds like you’re doing awesome! 
seriously there is soooo much proven info here i’m sure you’ll have no problems finding stuff to alleviate hubby’s concerns
One of the things I’ve noticed is the disconnect that some folk seem to have with their own body fat.
There’s an understanding that fat is a side effect of eating too much…and even that the body does use fat…but the idea that fat is food, that’s been set aside for use later is almost alien…because it conflicts with the common knowledge that we need to be eating all of the time.
I don’t direct this at anyone here…more just, processing…mainly because I did the unthinkable and tried to explain it to some family members just the other day ha…
It sounds like you are already burning body fat. It can take some people days or weeks, especially if they have severe metabolic issues such as diabetes, but a healthy person should be able to access body fat without major effort. A typical person might burn a little overnight and into the morning until they eat breakfast. It would be nearly impossible to maintain a steady weight if one couldn’t burn any body fat.
Myself, I was pre-diabetic with all 5 symptoms of metabolic syndrome in a bad way. I was a carb junky and couldn’t function without a steady infusion of fast carbs like orange juice all day long. I went cold turkey on all high glycemic carbs and processed foods more than halving my caloric intake. I felt awful for 2 days. On the 3rd day I felt better than I had for years and it was nearly effortless to maintain that intial pseudo fast for 3 more weeks. I suspect my fat cells were seriously overburdened by a lifetime of elevated insulin like over inflated tires about to pop and once that insulin was down the fat whooshed out. I miss those days of easy weight loss. I’ve got a few more excess pounds to lose but they are much more stubborn now despite being quite “fat adapted”.
Wow Todd! Good job. I’ve only been trying to loose the 20lb I put on in the last couple of years. Then of course preventing future issues and maintaining good health😊 I do feel adapted dispit my short time so maybe I’m lucky having been “normal and healthy” before.
Still struggling with my husband who is worried I have an eating disorder…
I’ve gotten him to see the light a bit on the science of the whole thing, but I don’t know how to argue with him when he thinks overall nutrition can’t be achieved with such restrictions…
Any sources to show on the nutritional stand point?
Cheers
The disconnect that people have is establish medical doctine is calorie in calories out (CICO).
Reality is the body is way more complicated by that and hunger and Basel metbolic rate are heavily driven by hormones (insuline, leptin etc…) Those hormones are driven largely by what we eat and our individualized responses.
Biology is widely diverse. Some people can look at weights and bulk up. Others lift and lift without nearly the same results. Some people can never crack a book and get straight A’s. Others study like hell to get a passing grade. I think our hormonal response to what we eat is the same. Some people have a highly adaptable metabolism and others ( myself) not so much. So some people get away with a carb rich diet are are ok. Others can not. So by being extremely careful to manage insulin blood levels by avoiding carbs (which stimulate insulin production) one can gain control over their body weight and hunger responses again.