[alecst]

For those who are curious, there's some anecdata online that extended fasting (days or weeks) can reverse this disease.

I can't find much published research on it to be fair, but I think the science in this field is lagging behind people's personal experiences.

If there's evidence to the contrary let me know, I'm not trying to spread misinformation. It's just one of the things I consistently recall reading over the years.

Edit since I'm being downvoted:

https://pmc.ncbi.nlm.nih.gov/articles/PMC6893587/ (prolonged fasting, ~8 days)

> The improvement of FLI correlated with the number of fasting days (r = −0.20, p < 0.0001)

https://eglj.springeropen.com/articles/10.1186/s43066-021-00... (ADF rat model)

> MSRDF rats showed cure of grade-1 NAFLD and significantly decreased LW than other groups and normalized HOMA-IR, HbA1C TC, LDL-C, ALT, and CRP.

https://www.cell.com/cell-metabolism/fulltext/S1550-4131(22)... (exercise + ADF, humans)

[cmrx64]

https://www.nature.com/articles/s41467-024-45260-9

this is the main thing I could find.

https://prolonlife.com/ sells a prepackaged fasting-mimicking diet. plenty of reviews online about the subjective effects on energy levels and soforth during the fast.

I didn’t like it. day 2.5-3 will put me back into the headspace of food scarcity and even knowing that the next meal was sitting in the box and that this is temporary … it was a mental challenge for me. if you’ve never experienced food scarcity, it can be all-consuming and seriously warp your cognition and emotional baseline.

[SlowTao]

Personally it is a strange thing. Diffcult to do over 24 hours but easy over a few days. Once you get over the head space of "im hungry must eat!" It turns into "im hungry, oh well".

But this is a sample size of 1 and results definetly vary wildly between folks.

[tshanmu]

I can concur - that shift in mindset to "i'm hungry, oh well" is crucial for your body I feel.

[cmrx64]

this is easier to do when you aren’t on the programmed diet that has you tantalizing your equanimity constantly.

[watwut]

> "im hungry, oh well"

The real danger is if you dont swap back and just created yourself an eating disorder.

[nradov]

That's not an eating disorder. Just because you're cold doesn't mean you need to put on a sweater. Learning not to let minor discomforts bother you builds discipline and character.

[watwut]

Anorectic are very dosciplined and proud of their ability to not eat. Hunger not being "well so what" is normal healthy biology. It is not just discomfort. It is biologcal mechanism to prevent very real harm.

Yhe issue with anorexia is that it works as cycle - if ypu have genetic predisposition, starwing affects metabolism, your discomfort about food gets worst and you are in it.

[GoToRO]

Fasting is great because you live off of your muscles. Keep at it and you will loose so much muscle, you will develop an eating disorder. The stomach and intestines are muscles too.

My understanding is that if you are healthy and you fast, it's great. If you are actually ill and fast it's still great but it only hides your illness and you are on a very bad path (eating disorder)

[ty6853]

Even cutting back a couple hundred calories a day can leave you absolutely exhausted, in my experience. Even just increasing exercise by a couple hundred calories a day without eating more is also incredibly exhausting, after a few weeks it becomes thought dominating second-by-second.

Hunger is truly a powerful driver.

[al_borland]

If you're going to fast, especially extended fasting, it would serve a person well to drop carbs and sugar and get into ketosis, at least for a while, so your body can start burning fat more effectively. If you've never done this before, it can be an uncomfortable process, with a lot of headaches, mood swings, etc. Making sure you take in enough electrolytes (sodium, magnesium, and potassium) will help a lot during all this, and during longer fasts.

I cleaned up my diet about a month ago, and have accidentally done some 24 hour fasts when I was busy and it's been fine. By the time I do eat, I'm really not even hungry, though my stomach may be growling a bit. The first time I ever did this, I had horrible headaches and felt miserable for a while, but subsequent times have been easier.

Good sleep maters too. Bad sleep will throw your hormones out of whack. I'm extremely hungry when this happens, and crave all the wrong things. Knowing what's going on helps a little.... just a little.

I find all this much easier than just trying to cut back by 200 calories with what I normally eat. It's all about hormones.

[GoToRO]

This sounds like a diet problem. You eat till your stomach is full. That because your food is not actually feeding you.

Long story short: meat and vegs + fruits. It takes a while.

[cmrx64]

and that’s when you’re doing it willingly :)

[SketchySeaBeast]

That feels like the incorrect framing, the burden of proof is on the initial claim. That'd be like saying "I've heard online that leprechauns live on the moon. I haven't found published research on it, but I think science in this field is lagging behind personal telescopic experience. If there's evidence to the contrary let me know, but I've read it online a lot." and treating that like it's proof of moon leprechauns.

[al_borland]

It's not exactly the same, as there are studies, there just haven't been a lot yet, since a lot of the study around it is new, although fasting has been practiced for thousands of years. There is no money in fasting, so the number of organizations willing to fund the studies goes way down.

To put some numbers to it:

https://pmc.ncbi.nlm.nih.gov/articles/PMC10564080/

> Only five out of the 1304 studies on NAFLD involved IF.

Here is one that mentions there may be some efficacy to the idea and no harm.

https://pmc.ncbi.nlm.nih.gov/articles/PMC8958240/

> In conclusion, current evidence suggests that intermittent fasting in patients with NAFLD is a feasible, safe, and effective means for weight loss, with significant trends towards improvements in dyslipidemia and NAFLD as illustrated through non‐invasive testing (NIT).

If someone has NAFLD, they can either sit around and eat cake for 20 years waiting for the science, or they can try doing some fasting, which is very low risk (assuming they don't have other issues going on), and find out very quickly if it works for them. Sure, it's an n of 1 in that case, but who cares, if they are the test subject it only matters if it works on them.

I'd add to this that the carbs should be kept low and the diet having quality foods outside of the fasts. Eating aforementioned cake during a feeding window every day is going to leave a person miserable, burning muscle, and still leave the hormones all screwed up. Insulin needs to be controlled and lowered. Fasting does that quickly, but don't abuse it during your meals on a regular basis.

From what I've read elsewhere, fasting can help in the early stages to reverse it, but once real damage occurs that sticks around.

[nradov]

There may be some medical benefits to periodic fasting, especially for people with excess adipose tissue. But in terms of "no harm" the Memel et al paper you linked doesn't seem to mention anything about loss of lean muscle tissue. This can cause serious harm for some patients — especially older patients with the "skinny fat" body type — by leading to sarcopenia (higher musculoskeletal injury risk) and endocrine dysfunction (muscle is a glucose sink). Loss of muscle can be limited to an extent by doing resistance training and maintaining high protein intake during non-fasting periods. But overall there are still a lot of unknowns in this field.

[al_borland]

A lot of that would be covered under the “other issues” I mentioned. Obviously, consult with your doctor first.

In terms of muscle loss, from what I’ve read, muscle loss is more of an issue for low calorie carbohydrate based programs. When fasting there might be some muscle loss when at the very start, but then it tends to preserve muscle, and like you said, adequate protein intake and resistance training can mitigate that.

Those, like Peter Attia, who saw muscle loss from long term keto and fasting over several years, weren’t using fasting as a medical intervention. He was already metabolically healthy, but maintained a pretty extreme fasting protocol in an effort to gain longevity benefits, effectively experimenting on himself based on some results of early studies around the benefits of fasting for longevity.

The general theory now seems to be making the fasts much less frequent once healthy. Maybe only a couple times per year.

I’m sure this area of study will continue to evolve slowly.

[watwut]

Add also refeeding syndrome to the list of risks. It can also serve as trigger for eating disorder.

Long calories deficit can lead to permanent brain damage too. And heart damage.

[SketchySeaBeast]

From your chosen quote, it doesn't seem to indicate that fasting specifically changed things, but fasting being an "effective means for weight loss" was the bit that really mattered. I don't see anything to divorce the two - general weight loss and improvement to the FLI.

> Available evidence suggests that any form of caloric restriction may be beneficial and specific forms of IF should be tailored to the individual.

Also important to notice that once the liver is damaged it's not recommended to fast:

> Additionally, it is important we investigate the possible risks of fasting in patients with cirrhosis, which is currently not recommended.

[apwell23]

so live a life of gluttony and "reverse" it in few days of fasting. seems like a good deal.