I have heard many people ask if people who’s weight loss stalls are eating enough calories? How does this work for someone who decides to have an 8 or 4 hour eating window?
If they purely water fast would there base metabolic rate slow?
If the fasted but still had coffee with cream would it slow?
Confused
A ketogenic diet is primarily a low-insulin diet. The idea is to eat in such a way as to keep insulin as low as possible for as much of the day as possible. The primary means of doing this is by lowering carbohydrate intake as much as possible, because the glucose that the carbohydrate is made of is what stimulates insulin secretion the most.
Insulin is necessary for the proper functioning of the body, the problem comes only when we have too much of it. So lowering carb intake is primary, but how frequently we eat also has an effect on our insulin level. Eating too frequently will also keep our insulin up, so the strategy is to eat only when hungry, stop eating when we stop being hungry, and not eat until we get hungry again. On a high-carb diet, the insulin that gets produced interferes with the other hormones that regulate our appetite, which makes us hungry all the time. By contrast, on a well-formulated ketogenic diet, people usually find themselves going hours between meals, because their appetite hormones have been restored to proper functioning.
The best way to get into fasting is to let it happen naturally. Most people eating a ketogenic diet to satiety find themselves so satisfied that they soon start to skip meals—because they simply aren’t hungry. From this, an intermittent eating/fasting pattern begins to emerge, almost without our having to think about it. The key is to be sure that when we eat, we eat.
The difference between fasting and restricting calories is that when we eat less, the body slows down to match the amount of food we give it (a famine response), but when we fast, the body simply switches from food to stored reserves, and the metabolism is not affected. This is so that when all the mastodon meat has been eaten, the hunters still have the energy to go out and take down a fresh one for the tribe. The famine response is needed to deal with a whole other set of conditions.
I have been doing OMAD fairly frequently during the week. I eat a (keto, high-protein) meal of 2500+ calories during a 30-40 minute period. So I’m fasting most of the day and also getting enough calories when I do eat.
It depends on how long the fast is, and how frequently it’s done. We do know from several studies of ADF (alternate day fasting), that the metabolism does slow over the course of many weeks. Notably, the metabolisms of the ADF group slow by less than that of the group using calorie restriction alone (but it still drops). Care has to be taken when evaluating the RMR drops in these studies; the majority of them allow 500kcals on “fasting” days and those results shouldn’t really be considered meaningful.
When we’re talking about fasts that are longer than one day, the true answer is that nobody knows the answer to that question. All published extended fasting research (mulit-day) has been done on subjects fasting for the first time. Frequent extended fasting is basically a black box.
A few folks do multi-day fasts frequently (several times per month), and we also own indirect calorimeters that allows us to measure our RMR’s daily during fasting. Our metabolisms do not behave anything like those of people fasting for the first time. Our metabolisms drop precipitously (250kcl-500kcal) after the first day of fasting, but pop back up when we start eating again. It’s not a bad thing necessarily and our RMR’s are higher than average people on feasting days. It appears to be a metabolic adaptation to frequent extended fasting, but since nobody has ever actually studied it, literally nobody has a clue how it happens or what it means (including me).
Dr. Fung talks an awful lot about resting metabolic rate remaining stable during extended fasting in his books. All of the research he cited was of people fasting for the first time. He has literally hundreds of clients doing frequent extended fasts, so he ostensibly has the best data. Ever seen Fung’s data on what happens to the RMRs of his clients after repeated bouts of extended fasting? Me neither.
In his IDM clinic (of which I am a former client), Dr. Fung’s advice is not to fast more 3 days in duration more than 4 times per month, with 4 days of refeeds between them. That’s probably not arbitrary, and it’s probably good advice to listen too. I’m a big fan of Dr Fung.
That’s my 2 cents.
What is the response when during the fast we drink black coffee with cream and butter. It really helps me to get through 
I have just watched Dr Fung’s video The Power of a 7-day Fast in which he says a 7 day fast is much more powerful for weight loss (I think he means compared to a 24hr fast). BUT he doesn’t say how often to do a 7-day fast. Fortnightly? Monthly?
Do you have any insight in to this, @Don_Q ??
In that situation you would likely halt autophagy but elicit little or no insulin response.
I tend to think of drinking bulletproof coffee or other fat-only ingestion as fasting with respect to carbs and protein - I.e. 2 of 3 macros. I don’t know if anybody has given it a name, but it could be “2/3 fasting” or “partial fasting” or something like that.
Dr Berry says the cream stalled his weight loss. He prefers butter in his coffee and a little bit of salt.
I’m hopefull I an still do this as it appears to help me get through. Weight loss is slowing at around a pound per week at the moment.
I think a seven day fast is a bit like pressing the “reset” button metabollically. You don’t need or want to do it very often. Fung says that when he has a patient at imminent risk of amputation due diabetes, he’ll have them do a fast a week or longer under medical supervision to make a big impact quickly. Once that intervention has been done though, it isn’t repeated.
When I was a member at IDM last spring, there were two recommended fasting regimens for reversing metabolic syndrome: one 72hr per week, or ADF. I watched an interview of him by Dr. Mercola recently where he said that he’s moved away from the longer fasts for weight loss in most cases because in his view, frequent short fasts are effective, and lower risk.
If someone wanted to do one 7 day fast annually I don’t think he’d argue against it. A current client of IDM might have more up to date info though.
Not to quibble over semantics, but it might be more accurate to say that autophagy would be downregulated when we consume cream. We still have autophagy going on even when we’re munching on a ribeye and eating french fries. I don’t think I’ve ever seen anybody quantify how much it’s downregulated when eating pure fat though (10% vs 50% vs 75%). I’m not sure anyone even knows. If anyone did, I’d guess it would be Prof Vlongo, but I haven’t read a lot of his stuff.
Alternate day fasting is the one I prefer. I used to OMAD at least five days a week, but have gotten better results with a couple of alternate day water/salt fasts followed by 16/8 windows and three meal weekends (breakfast just doesn’t work in my schedule during the work week). If I was trying to heal liver, kidneys, reverse type 2, I might would try and go longer at times. I might do a 3-5 in the next month or so if I feel up to it, just for the autophagy benefits.
I’d like to add that fat does raise insulin. It doesn’t raise it as much as protein or carbohydrates but it’s not nothing either. Jason Fung has said that although it would be hard to eat this much fat for anyone it’d be technically possible to develop insulin resistance just from overconsuming fat. The people at Paleo-Medicina say that they see reduced ketones in people who are overeating fat.
If you’re trying to fast you shouldn’t assume that butter had no detrimental effect on your efforts.
Yeah, I don’t personally call it fasting if I am eating fat.
Maybe it’s still beneficial, but I consider it to be something other than fasting.
Coffee, water, tea are fine, but anything with non-zero calories breaks the fast, in my interpretation.