- No exploration in this study of the effects and/or benefits from the gene expression.
N=1 but I've been doing ~16:8-ish along with strict keto for the past five years and the net benefits for me have been transformative in fitness (Weight: -100+ lbs, BMI: Obese->Fit), long-term health (A1C, LDL/HDL, Trigs, BP, resting heart rate all from bad to great), cognitive acuity and emotional stability. First 12 weeks required serious effort/focus to transition habits, palette and metabolism (must RTFM and be rigorous) but after that it's been surprisingly easy to sustain long-term, requiring no will power or conscious effort.
Other surprising experiential learnings: Dietary intake impacts long-term mental/emotional states FAR more than I ever suspected. Food & taste prefs I had since childhood are not innate. Many things I loved no longer even taste good. Hunger pangs and cravings are driven by my blood sugar cycle. Once I stabilized that I no longer get hungry or feel food deprived/obsessed. (<--- all N=1 of course.)
To give another N=1, I don’t feel good on a 16:8 split. At least not when the eating window starts at noon. Long term (18 months) this zapped my energy and I lost a lot of muscle. Yes, weight loss was phenomenal, but I gained all of that back in the phase of exhaustion that followed.
What has worked better for me was longer fasts, eg 48h, max once per week. And lately I‘ve been experimenting with skipping late dinner (no food after 6PM) which is kinda hard but seems to work for improved sleep and digestive health. I usually have visible bags under my eyes, those tend to be greatly reduced when I eat an early or no dinner.
> Long term (18 months) this zapped my energy and I lost a lot of muscle. Yes, weight loss was phenomenal, but I gained all of that back in the phase of exhaustion that followed.
Muscle loss is an adaptation to loss of load on the muscle. Internet trope of "you lose muscle when you lose fat" is just that - a trope. If you were 100lb heavier, your muscles were loaded with extra 100lb. Should you lose the 100lbs, if you do not engage in the appropriate resistance exercises to provide equivalent of additional 100lb load, your muscle mass will decrease
I had similar improvements without fasting and without keto. I do 16:8 on some days but it's mostly to help me manage my weight. I strongly believe most of the fasting benefits come from the fact that it makes managing weight easier.
Calorie restriction and tracking my macros has helped me tremendously not only loosing weight but also understanding nutrition and what works for me and what doesn't. I am a 40 year old Software Engineer and fitter and stronger than I have ever been.
I do quite a bit of high intensity cardio (cycling) + weight training and my recovery and peak performance suffered a lot when I tried keto for a few weeks, it also tanked my hormone levels. I still focus my carb intake on times around training but generally don't restrict.
with blood work, I had some symptoms as increased fatigue, libido gone and similar which can also come from extended calorie restriction together with intense excercise anyway, so its not necessarly keto related.
For me the benefits seem to be a lack of carb cravings, and my fullness indicator turned on for the first time in my life. That was with 20:4 though, and no keto.
You need to stay on it for months to become keto adapted. I would say 6 months minimum, after that the energy swings go away and you generally have a lot more energy. You can also add MCT oil. The problem with keto is eating enough calories.
In my experience, it's exceptional in America. This may be due to constant indoctrination that "breakfast is the most important meal of the day". Also, modern food processing has put all sorts of late-night snacks at our fingertips.
Given the amount of disagreement, I'd expect it is common enough but with some multimodal distribution tied to culture, geography or job type, so that the two modes don't notice each other. Happens with lots of stuff. My N=1 is that I probably know fewer people who skip breakfast (to include calories in coffee) than I do people who do 20:4 fasting. I like how I felt on 20:4 but it is easy to fall off of for social reasons, and womce I do, the blood sugar related cravings come back so I need a 48H water fast to get back into effortless 20:4.
Hard to imagine skipping breakfast, lunch, coffee/tea w/milk & cream, and all snacking during the day, everyday is normal outside America. Isn't burned bread with beans or butter for breakfast a thing in the UK?
16:8 means if your last calories are before 10PM, you wouldn't eat anything at all until after 2 PM. And this would be every day, not every other day.
It’s more common in parts Europe than you’d think I guess, with the last calories around 8-9pm until 1pm (or 11pm until 3pm a bit southwest of here) there are variants around that of course and I’m less sure how common this is everywhere in Europe, but where I’ve lived a lot of us eat like that. It’s not some fad just a long held habit, not sure where it came from or why so many of us seem to do it here.
That said, it is changing by the day and I see more teenagers snacking at odd times.
> sounds like a very normal day for lots of people
That's the issue with your statement. I didn't survey "lots of people" and neither did you. I can't find any data to back it up, but I do see a plenty of surveys about breakfast consumption.
I find it very hard to believe people are restricting their calories within 8 hours everyday, naturally just based on the conversations I've had with people. Even in this thread people say they've tried it, and found it to be too difficult.
It's simple: People enjoy eating. People eat when they're bored, because of habit, or socially. No reason to believe they abstain from those things 16 hours a day.
It's not like all of that 16 hours is sleep. On average, more people are getting less than 7 hours of sleep.
Fasting is not an on/off switch, but too many calories (>10-20) in a short amount of time pushes you out of a fasted state. It's very likely people are snacking or drinking calories within those hours after waking, and before lunch.
Also, some people will often over eat one day, and then under eat the next. This could help get through a 16 hour fast a few days every week. I think those times are usually over represented when self-reporting these habits.
If you mean a full meal, sure. However, I suspect the majority of people enjoy some calories pretty early in the day. Sugary coffee/tea, cereal bar, bagels or other grab and go snacks.
That's the thing. Most people would greatly benefit from the unremarkable lifestyle change but a lot of people cannot do it due to reasons and a safety net.
N=1 and also probably too many variables to learn from this - keto itself is already a massive lifestyle intervention. Did you restrict calories as well? Exercise?
I started IF only after I had been doing keto for about six weeks. At that point it was frankly easy because I wasn't getting hungry or having cravings anymore. I can't tease out how much IF contributed but I'd already lost a remarkable amount of weight on just keto. In general, I'd recommend only making one significant change at a time.
Calorie tracking and restriction pretty much comes with strict keto. Transitioning to keto rigorously requires detailed tracking of every molecule that goes in your mouth (with a food scale and measuring cups), at least for the first 12 weeks. I tracked constantly for about 6 mos until it was automatic for me and I knew every food and portion I typically encounter at a glance. It's hard at first but only tracking part way is the #1 reason for failing to get results.
I didn't do any exercise at all while losing weight, in fact while changing diet I was more sedentary than my usual slug-like activity level due to work and life factors. For me, exercise has always been hard, unpleasant and inevitably makes me hungrier. N=1 but that's what worked best for me and my weight loss was dramatic and super fast (>100 lbs in 8 mos).
black coffee and plain tea are acceptable according to everything I’ve read, probably because they are close to 0 calories and certainly not nutritional calories if >0. So I drink them. Unfortunately there’s no way to know if you’re still in a fasted state after that coffee. You can test blood sugar with a pinprick and that is a marker, but not a guarantee.
What's interesting to me is that there is strong support from data that skipping breakfast causes many people to eat more later, in particular eating more carbs/sugar/snack foods. I have to wonder to what extent a planned 16:8 window where you're conscious about having a good "break-fast" meal is different than simply running out of the house without a meal plan in place. It is very clear from the data that simply "not eating breakfast" does not lead to better outcomes.
I also find it interesting that the gender of the mice was not specified. If we're talking about hormonal profile changes, this will matter. When intermittent fasting was very popular, a number of women in "the scene" with a vested interest in making IF work noted that while initially it was great, they eventually started experiencing adverse effects, and often felt better on a 14:10 window instead.
Agree with you on the last paragraph re: your experiences. I've needed to substantially change what I eat due to some health challenges, and blood sugar is huge. Protein in the morning (rather than something like oatmeal) is key for me. A dozen eggs a week and my hereditarily-high cholesterol went down, too. Sorry oatmeal folks!
> there is strong support from data that skipping breakfast causes many people to eat more later, in particular eating more carbs/sugar/snack foods.
There's a big difference between skipping breakfast one time and habitually skipping breakfast. The body adapts. You no longer feel hungry in the mornings and you develop new eating patterns - since most people doing IF are focused on health, these are likely to be healthy eating patterns that don't include lots of sugary snacks. Apparently this adaptation takes the form of the liver learning not to expect breakfast after waking and producing glucose at that time, although I have not personally checked the research on this.
I've been doing IF 16:8 for about a year now. I rarely eat processed sugar (except a good croissant a few times a week). Even some fruits like ripe mango taste too sweet to me now.
From personal experience and discussing this with other people, if your fear is that you'll end up getting so hungry that you'll stuff your face with junk, it's not a valid fear beyond the first week. To avoid this I would suggest easing into it. Eat breakfast an hour later for a few days, then two hours later, and finally combine it with lunch.
I have been doing similar for about 3 years now, with similar results, but one thing that has been problematic with for me... is my bowel movements just don't seem to function well when I'm doing keto. The only thing that seems to fix them is milk+cereal... (fiber from veggies don't seem to quite cut it). So I kind of alternate between periods of keto, and a normal diet. How do you do strict keto?
Very low carb keto is known to stop you up, if that is what you are referring too. I didn't get any issues, but I kept my carbs a little higher than my wife who regularly did have issues. A small glass of salty water fixes it. Don't venture too far from a bathroom after ingesting.
N = 1. 18:6 for me. 2PM to 8PM, with occasional falling off the wagon due to social obligations or just simply forgetting to eat and then realizing I need to eat. I have noticed if I eat sugary snacks with my last meal that I get ravenously hungry much earlier the next day. There are some days where I unintentionally forget to eat until 4PM or so.
I tried 16:8 but it never seemed to have any effect on weight loss for the 2PM to 10PM range. And my weight would creep up with that regimen. I suspect that might be related to late night hormonal changes in the human body preventing the digestion of certain types of food. I should try a 16:8 with 12PM to 8PM at some point and track the results.
There are also studies showing both keto diets and fasting can alter the microbiome and attributed changes in gene expression to changes in the microbiome.
Agreed. Another additional benefit in my opinion is that when restricting your feeding window, it’s much easier to control cravings. When “free-eating”, it’s easy to just continue to snack.
- In mice.
- Tested 16:8 pattern.
- Sustained consistently for nine weeks.
- No exploration in this study of the effects and/or benefits from the gene expression.
N=1 but I've been doing ~16:8-ish along with strict keto for the past five years and the net benefits for me have been transformative in fitness (Weight: -100+ lbs, BMI: Obese->Fit), long-term health (A1C, LDL/HDL, Trigs, BP, resting heart rate all from bad to great), cognitive acuity and emotional stability. First 12 weeks required serious effort/focus to transition habits, palette and metabolism (must RTFM and be rigorous) but after that it's been surprisingly easy to sustain long-term, requiring no will power or conscious effort.
Other surprising experiential learnings: Dietary intake impacts long-term mental/emotional states FAR more than I ever suspected. Food & taste prefs I had since childhood are not innate. Many things I loved no longer even taste good. Hunger pangs and cravings are driven by my blood sugar cycle. Once I stabilized that I no longer get hungry or feel food deprived/obsessed. (<--- all N=1 of course.)