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Intermittent fasting for the prevention of cardiovascular disease (nih.gov)
55 points by JPLeRouzic 12 days ago | hide | past | favorite | 40 comments

Negative results are still results and are useful.

Nobody disproved anything. They have no clinical confidence to say anything, just an observance that IF people lost weight better.

Yes but not significantly better. And there were quite a few studies to choose from and still quite a few left after filtering for the best.

It's a fairly strong statement that despite a lot of studying, no evidence of any meaningful benefit for weight loss, and no benefit at all for CVD is found.

There could be other benefits, of course.

In fact, personally, I tried IF and what I found to be the greatest benefit was sleeping better. All I really have to do to maintain that same benefit is stop eating a couple hours earlier than I did before IF, and that's ... if we're being honest here ... that's long and well known good advice: don't eat near bedtime. For me it just didn't click that it meant don't eat several hours before bedtime as opposed to say, 30-40 minutes before bedtime.

Anyway, it's not surprising to me that little benefit is discovered so far from IF. It is an interesting idea, but, not much of a mechanic associated with it to explain any benefits. Most aspects of our metabolic processes do not work timeframes below a few days.

Actually, the parts that DO work on short time frames related most strongly to the health outcomes they stated could not be judged by the studies, including glucose impact. So I guess cross your fingers that in the future it can be shown that IF helps glucose management and reduces diabetes risk/impact.

I'll try saying it a little more verbosely, perhaps.

There is no evidence from this trial to refute the null hypothesis, which is to say there is no evidence from this trial that IF provides any protection from CVD.

As someone who’s lost 15 pounds since Christmas doing nothing but eating in a restricted 2 hour window rigidly most days. This doesn’t surprise me. Long low blood sugar periods and it’s much easier to get a single window of eating under control.

I think is genetic because I have noticed that for me best way to lose weight is to pretty big calorie restriction(about 1600kcal daily) with lots of protein (120g<). I have tried intermittent fasting and personally I don't like it I am always very hungry or it does not affect my weight.

In studies, caloric restrictions had shown to slow metabolism, which leads to reduced weight loss over time. Then when a person rebounds or quits, then all of that weight comes back even quicker.

I encourage you to try IF for a longer period. A week or two. There’s an adjustment period after which it becomes easier and then becomes the norm.

Also I find low carb, but not necessarily keto works better with IF. Essentially the goal is not to spike insulin too often.

Different stratgeies will work for different people. Is it genetic, phsycological, emotional, a combination of each, I don't know?

The reason IF works for me is that I know I can eat pretty much what I want so long as it's reasonably healthy (lots of veg, fruit) and I only do that once a day.

A traditional calorie controlled diet works also in the short term but it's miserable and, eventually, I break just as, anecedotally, most other people do too

But.. but... they didn’t report significant effects

The problem I have with diet research is that the studies (and the internet commenters) are always looking for one thing that everyone can do and get good results.

The body is a complex system, and different people's bodies work differently. Really, what I want to know from a diet study is were their negative effects, and did it work for a significant amount of the people. Ideally, for those who it seems to work, do a longer term study to look for negative effects and long term results for people who stick to to it. If you get enough of these studies, and I'd like to change my diet to control my weight, I can try things until I find one that seems to work for me, and have some confidence that it works long term for people who it works for.

One diet to rule them all is the same thing as everyone should run the same HTTP server. I love apache, but different systems work better with different servers.

Our heuristics tends to find a pattern in things. The problem with this behavior is that there is no "silver bullet" solution or pattern ...

What I am trying to say is, you are totally right here. I suffer from IBS, and if I just try IF for one day my entire guts go really nuts (I have mixed type of IBS).

There seems to be an inherent assumption built into all of these kinds of studies that all humans are identical interchangeable units. You don't see a lot of "this intervention is wildly successful in 20% of subjects and useless in the rest" type results advertised.

Yeah, I get the impulse, and there are studies which try to partition subjects into “responders” and “non-responders”. The problem is if you don’t set out the partitions before you start the study then any ex post facto partitioning is fertile ground for p-hacking.

The correct thing is to do the exploratory study, notice that some group seem to respond well, then run a new study “IF for the prevention of CVD in <specific subgroup>”. That’s a lot to ask, of course.

That makes sense. I guess the real trick is to figure out what the key distinguishing factor for that particular subgroup is...

So it doesn't prevent it? It should say on the subject! Wasted time reading..

It said it was better than random eating.

> However, this was not clinically significant

It did not say that.

“Intermittent fasting was seen to be superior to ad libitum feeding in reducing weight.”

Insignificantly better.

"Intermittent fasting was seen to be superior to ad libitum feeding in reducing weight. However, this was not clinically significant. There was no significant clinical difference between IF and CER in improving cardiometabolic risk factors to reduce the risk of CVD."

Edit: Removed own interpretation to let the authors speak for themselves

That doesn’t say it doesn’t.

It doesn't say it doesn't not do it not somewhat

This is just a jumbled survey of existing papers that doesn't even distinguish between IF and TRF!

How does long fasting affect brain function?

Somebody needs to come up with a less pretentious way to say “skipping breakfast”.

Personally I just say “I don’t eat breakfast.”

If that’s all you think IF is you are way off the Mark.

No, it's correct.

Most people define IF as eating within a 12 to 6 hour period each day. For most people this is literally just skipping breakfast and eating lunch & dinner.

That's only if you already don't snack as after dinner. I already skipped breakfast, so in my case, intermittent fasting was really just about not eating anything after dinner.


Actually doing IF is more like, you have a 6 hour window a day in which you eat, and you eat nothing outside it. For most people that's much more restrictive than "skipping breakfast."

That said, not everyone agrees on the method. Some will skip entire days intermittently, so, this whole discussion is shaky overall, but, definitely agree that "skipping breakfast" is not IF.

“Skip breakfast and eat an early dinner. Don’t snack.”

Eating only 12:00 to 20:00 can be achieved for a lot of people by only skipping breakfast and not snacking in the evenings and still falls under the (broad) banner of IF. It's quite a popular variant.

Intermittent Fasting (at least as I've seen it practiced) generally lasts more than one meal. Sometimes more than one day. It really flushes out your body, which can sometimes make you feel a whole lot better.

Can you explain what you mean by “flushes out your body”?

There’s a huge variety of variants of intermittent fasting.

Which one is the orthodox or most effective one for a given general population ?

16/8 and alternate day are the most studied and popular to the best of my knowledge and seem to have pretty similar results. As said, there are countless variants out there.

For me personally, „skipping breakfast“ comes close enough as an oversimplification in practice.

The one I've heard most about is 16:8, which would mean e.g. first meal being lunch at 12 and last one dinner before 20, resulting in a 8-hour eating window, and a 16 hour fasting one.

That can be the same, but for most people would probably not be. IF means having a fast of about ~16 hours, giving you an eating window of 8 hours a day. So if you skip breakfast and eat lunch at 11, your last piece of food should be around 19. Most people when they don't eat breakfast, though, will probably have a small snack with their morning coffee, or even just some sugar in it (thus starting the window). And might also have some more food late in the evening a few hours after dinner.

Most people will also never be on board when one touts it as "skipping breakfast", as for them that's a negative experience. For me, never eating breakfast is ok, as my body is used to it. But for those used to eating it, the days they don't get their breakfast equals a bad morning. Either because of the circumstances leading to them not getting to eat (overslept, stressful morning), or in combination with an unusual feeling of hungriness and tiredness.

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