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Comment by moneywoes | Hacker News Reader

Seems like there’s numerous conflicting studies regarding intermittent fasting especially when different fasting periods are taken into account. Is there any conclusive research regarding just having 2 meals a day? That seems to be the easiest to integrate in day to day life.

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Is it even possible we ever end with conclusive research that could be applied at large scale ? I think you won't have much choice than try and see if it works for you specifically.

We could have more lab mice studies, but it wouldn't account for actual humans' different metabolism, include lifestyle (work, daily rhythm, mental state), actual food intake, genetics etc.

Looking at other human related health subject, for instance we haven't hit any conclusive point on any specific food that is widespread today. Everything regarding fat, proteins, sugar etc. is still small scale, extremely biased, often politicized and producing contradictory results. All we know for sure is that "too much" is not good, and that's after decades and decades of research.

I think it's hard but absolutely posssible, but the quality of statistics in nutrition research depresses me. Good work exists, but the publication incentives do not lead it to rise to the top, meaning the correlation between study quality and study size isn't good. AFAIK, and I am not up-to-date, there are no large studies that (i) are constructed to gather data on enough variables and (ii) do the data gathering well-enough that the data won't be too noisy.

I'd love to learn that I am wrong.

For me it involved skipping breakfast. It was an easy transition, because normally I'm not hungry in the morning anyways. I would eat breakfast mostly out of force of habit.

Same for me. In addition to that, having breakfast actually caused me to get hungry again pretty quickly and generally start feeling terrible if I then didn't eat again, whereas without it, I could pretty much go all day, no problem.

Exact same experience here.

I can easily go from 8 in the evening to 11-12 the next day without eating. Maybe a bit of water or some caffeinated sugar-free drink in the morning.

BUT, if I eat a bowl of oats (as recommended) at 8, I'm _hungry_ at 10, like starving-hungry.

I can also just eat a large-ish lunch and go until evening pretty easily.

This has been my experience over many years of restricting my consumption window. I also find I get mid-morning and after-lunch energy wells if I have an early breakfast, not so much if my first meal is after 10am.

Breakfast actually made me feel physically ill for a while when I was in my early 20s, so I skipped it out of necessity. I think it had something to do with insomnia. Keeping down half an apple was a struggle. So I basically starting skipping entirely.

These days a single coffee with some milk is enough until lunch, whenever that is. I can eat breakfast (or at least brunch) decently well now, but like you say I just get hungry again anyway. And if I'm going to the gym any time before 1pm I try to eat nothing beforehand or I just feel worse.

I wonder how much that splash of milk in my morning coffee breaks the magical fasting spell.

This opinion gets repeated a lot. I’m the complete opposite. I wake up wanting food and have made dinner my skip meal. Seems to work well for me.

Not an expert, but from reading studies I suspect that the specifics like which meal to skip can vary by person. Which makes sense since we all have unique physiology. Eg, some people are natural night owls vs morning people. There’s plenty about the body we don’t fully understand, but executing discipline to follow a generally-healthy eating regiment likely has both direct physical benefits and benefits from a sense of control and well-being.

Everyone is different, do what feels right for you

I did one meal a day for a few years and lost an OK amount of weight and felt pretty good. But then I fell off the wagon and it wasn’t easy to start up again.

So now I’m trying a 48 hour fast once a week, and not changing much else. Starting week 5 tomorrow, and it’s looking promising so far.

> But then I fell off the wagon and it wasn’t easy to start up again.

Just wanted to say, based on my extensive experience with fasting, this is normal. There seems to be a psychological barrier about how easy it 'should' be or 'used to' be, and you beat yourself up about it which makes things even worse.

Every time I've made a habit of extended fasting, or prolonged intermittent fasting, and taken a break longer than 6 to 9 weeks, restarting is very... very hard.

I'm curious if you considered a 4 day fast every other week instead. The first two days are the hardest days of an extended fast (hungry, lethargic), so you might find this approach easier and more beneficial.

I’ve found coffee and the occasional 200mg caffeine pill with 400mg of L-Theanine helpful to push through the first day of a multi day fast, when your body is complaining about burning up its glucose reserves.

I’d love to give this a try, do you not workout during these or?

Yes, I work out daily, 30 minutes on a row machine, 30 minutes strength training. Strength training has been found to protect muscle tissue from wasting during fasts, and the cardio is because I enjoy it.

I did the same thing but I just went to 80~85% of my usual lifting weights and a 3km walk in my lunch breaks.

That's an interesting idea. The only thing that would give me pause is I know I'd get a lot of "Oh, look, dad is being weird and not eating dinner with the family all week again". The 48 hours is basically "hey I'm skipping dinner tonight".

How’s your energy level throughout the 48h fast?

I feel pretty good, the only issue is just a sort of stomach discomfort that isn't quite hunger and not painful. More of an "empty" feeling. But mentally I am focused.

I don't have any hunger the whole time as long as I don't drink any coffee. For some reason it makes me ridiculously hungry and I just give the whole thing up.

Coffee is high acidity and I remember reading (can’t source) that it should not replace breakfast for that reason.

Wondering if replacing it with green tea could provide some of the caffeine in less acidic form.

I’ve had one meal a day for years. We just eat around 7p and I have a milky, unsweetened coffee in the mornings. After a while you don’t even feel the urge to eat lunch anymore so there’s no chance of “falling of the wagon” as another GP has mentioned.

The autophagy research that won the 2017 Nobel Peace prize lead to the explosive interest in fasting for cellular health/longevity.

There are now thousands of studies published per year related to fasting and autophagy. IF is a byproduct of this interest.

Autophagy isn’t generally reached with most IF schedules (generally around the 24 hour mark and peaking around the 36 hour mark), but a lot of these studies are measuring other possible benefits and bio markers of IF.

The answer to your question depends on your goals, but if you are fasting because of the hype around longevity I would suggest focusing on 2-3 day fasting periods rather than IF.

Could you share some supporting articles regarding 2-3 day fasting?

this cites some research for what happens during the stages of fasting.

https://usetemper.com/learn/metabolic-step-by-step/

Studies also seem to show that the trigger mechanism for many of the benefits is caloric restriction and not the fast.

As when fasting we do need to eat at some point.

Please define conflicting (largely positive but under different conditions, or something else?), and list the studies in question.

> having 2 meals a day

Intermittent fasting isn't about reducing the number of meals, or in theory the total calorific intake, but rather the window in which food is consumed. That said, it's entirely possible that one influences the pother.

You have to have enough of a food shortage to get your body to shift into more autophagy/catabolism. It doesn't really matter how often you eat as long as you can generate that shortage. The initial studies had long/significant calorie restriction, and all the fasting schedules are ways to make them more tolerable.

I came to a conclusion two meals a day after finding out where the three meals a day concept originated.

The intermittent fasting in this study was every other day feeding by the way.

I find that to be one of the hardest regimens.

Agree. I'd rather do One Meal A Day, or 5 days Fasting 2 days fed, or basically anything but every other day.

Of course, I'm not locked in a cage in a lab with no choice.

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