I’m sure this has been covered elsewhere but if you could point me to some papers I’d love to read them

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This is a landmark paper from the famous Nurses’ Health Study:

and a (slightly) more recent Meta-Analysis to round it out:

To be clear it is perfectly possible that a well constructed low carbohydrate diet using unsaturated fats, more plant protein, plenty of fibre etc could be a very healthy diet but the population data shows people performing worse on low carb diets.

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Exactly, see these 2:

https://www.thelancet.com/journals/lanpub/article/PIIS2468-2667(22)00118-9/fulltext

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6959586/

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I have been retired for many years. Before I retired my eating patterns and time of eating were dictated by conventional social norms i.e. breakfast when I woke up, lunch at noon, and supper sometime after 6 PM.

When I was a child I never wanted to eat breakfast because I was not hungry and couldn’t understand why my mother insisted on eating breakfast.

After I retired I went on an intermittent fasting keto diet to lose the weight I had gained in the last few years of my job.

Because I am retired there is no social pressure to eat at certain times. I have evolved naturally into eating two meals a day. I eat breakfast when I first feel hungry, which is usually around noon, sometimes as late as 1 PM. I eat a light supper at 5 PM. Any later than that affects my sleep. This is a natural rhythm for me and not a forced pattern.

I think most people have some natural eating rhythm but are forced by social, work, or family traditions. I think it is hard to find your natural rhythm unless you are not bound by work schedules etc.

Bottom line: After being on natural (for me) time-restricted feeding for seventeen years my BMI is currently 20.1 and my blood markers, many of which I have posted on other threads, are excellent even though I take relatively high doses of rapamycin.

Eating three meals a day emerged during the Industrial Revolution and became standard by the late 19th and early 20th centuries. It was driven by changes to working patterns and lifestyles.
Before this, most people ate two meals per day.

In the 1920s-1930s, breakfast was promoted as the most important meal.

“Emerging findings from studies of animal models and human subjects suggest that intermittent energy restriction periods of as little as 16 h can improve health indicators and counteract disease processes. The mechanisms involve a metabolic shift to fat metabolism and ketone production, and stimulation of adaptive cellular stress responses that prevent and repair molecular damage”

“It may be reasoned from an evolutionary point of view, that the human body is physiologically habituated to less frequent meals”

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Can’t help but get a chuckle out of that statement (even tho I know exactly what you mean). But it makes me think of…“I’m still fully functional and sharp even though I’m on heroin.”

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My point was that this study (91% more likely etc) is drawing its data from the same population that the studies that show higher all-cause mortality drew from. Out in the wild low carb diets perform worse and my theory was that this data was just reflecting that.

Regarding the links you posted one is just correspondence from a low carb and keto diet advocate Richard Feinman so I’ll leave that aside for the moment.

The other paper is interesting but doesn’t seem to contradict my earlier points. With the 12 studies they chose people lost weight and had reductions to triglycerides and blood pressure which is exactly what you would expect for people losing weight. LDL also went up slightly at 6 months. It isn’t a large meta analysis with fewer than 2000 people overall with fewer than 1000 following the low carb diet (for context the meta-analysis I posted had 270,000+ people overall). Furthermore it isn’t looking at outcome data (deaths, cardiovascular events etc) but just biomarkers so not particularly strong evidence for positive health effects of low carb diets.

I don’t want to drag this thread off topic as it is an intermittent fasting thread but to summarize my general position again low carb diets can be healthy but the way they are practiced by the general population usually isn’t.

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I agree but relevant to the thread, you need to look at why people are eating a low carb diet or practicing time restricted eating. If they are doing it deliberately, to improve their health, that is generally a good thing.

Maybe a bit too much analysis here. This is a retrospective association study which makes it almost worthless. Treat it as such.

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I don’t believe that retrospective studies are necessarily without value, because they ultimately observe a hard outcome: whether the person lived or died, whether they got sick or not, rather than the intermediate changes in a metabolic indicator. It’s not about observing the short-term biochemical changes in a person. A 90% increased risk is very high. We still need to look at this issue dialectically. I think it has some reference value.

I understand your point. I would add this as a retrospective study - if humans needed to eat over 12-16 hrs a day to do well, we probably would have died off millions of years ago.

And, I would add that it’s the association part that’s really puts it in doubt.

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Matt Kaeberlein’s take:
All the influencers are losing it over the new report that intermittent fasting is associated with a 91% increase in heart disease death. Obviously many caveats, and not published yet so don’t know what other flaws exist, but this seems like a pretty big effect and probably worth not ignoring completely, just because you don’t want to believe it’s true https://washingtonpost.com/wellness/2024/03/18/intermittent-fasting-time-restricted-eating/… I’ve said all along that fasting/intermittent fasting/time restricted eating have little to no benefits if not also paired with a reduction in overall caloric intake. The animal data seem clear on this, at least from a longevity and healthspan perspective. We published a comprehensive review on this a couple of years ago. https://ncbi.nlm.nih.gov/pmc/articles/PMC8841109/… Intermittent fasting or time-restricted eating in people can lead to reduced muscle mass - seen previously and also in the recent reports. That can likley be overcome by diet quality and resistance training, but requires some thought and effort. Loss of muscle mass is a problem and may be contributing to increased mortality here and in general. My advice: (1) If you want to do IF/TRF to control weight, you really need to focus on a high quality diet and do some resistance exercise to maintain muscle mass (2) If your doc or favorite internet personality isn’t telling you this, you may want to seek information elsewhere (3) Don’t do IF/TRF because you think it promotes longevity. It doesn’t, even in mice, unless it’s in the context of caloric restriction

https://twitter.com/mkaeberlein/status/1770440009574752761

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Medscape posted the study and the response so far has been 100% negative, calling attention to various sources of invalidity.

“Someone has slipped a cog. Two self-reported dietary recall responses in 2003, assumed to have validity over a 20 year span. Really!”

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If you know the causes of heart disease, you know it is impossible for IF to increase RR by 1.91 as there is no possibility for that within the rules set by the simulation :wink:.

There are only a few dials on heart disease risk. Once AI becomes better more people will understand this.

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Interesting article:

Insulin Resistance Is A Stronger Risk Factor Of Cardiovascular Disease Than LDL-ApoB

Awww, they chopped the best part off the headline. This chart sums it up pretty well:

LPIR stands for lipoprotein insulin resistance, which is measured by NMR technology. Don’t ask what it costs.

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Surprising similarity to what @John_Hemming just posted in an article about “Strengths And Weaknesses Of Longevity Biomarkers”.
https://spotify.localizer.co/t/strengths-and-weaknesses-of-longevity-biomarkers-vitadao/12857?u=ng0rge

There it’s a blood measure called 2-hour post-challenge blood glucose (2h-BG) test. Here’s a comparison:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3136064/

Your article says “Meanwhile, the LPIR Score can be obtained with a single fasting blood sample and it is relatively affordable.”
While the other article says " a number of techniques such as euglycemic clamp technique, insulin tolerance test, insulin sensitizing test, i.v./oral glucose tolerance test, fasting insulin levels, and fasting glucose to insulin ratio have been devised by several investigators. However, all these techniques are time consuming, expensive, stressful to the patients. Besides, the high cost and nonavailability of newer technologies is also a hindrance. Recently, “2-hour post-glucose insulin levels” has been recognized as a possible indicator of IR. Therefore, a single “2-hour post-glucose insulin level” appears to be a reliable indicator of IR in PCOS patients. "

Just pulled this up: $33

https://www.walkinlab.com/products/view/glucose-two-hour-post-prandial-blood-test

And for LP-IR there’s this:

https://www.findlabtest.com/lab-test/general-wellness/lp-ir-score-labcorp-result-code-884314

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Yeah, that was kind of click bait. I had to look up what NMR even is (nuclear magnetic resonance) and on wikipedia it showed a pic of a huge machine and talked about the physics of the thing. I couldn’t find the actual blood test.

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This is the best explanation out there about the Kraft curves and that would be the $33 one.

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Life extension offers the LP-IR test economically as part of a detailed cholesterol panel. I added it once to their Elite Comprehensive panel. I need to do it again. The price has been dropping steadily over the past few years.

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最新

You may have seen the headlines: “Intermittent fasting linked to 91 percent increase in risk of death from heart disease”; “The intermittent fasting trend may pose risks to your heart.”

The news came from an abstract presented Monday at an American Heart Association conference in Chicago. The study has not yet been published in a peer-reviewed journal, and experts cautioned that it had many limitations. Here’s what we know.

The Limitations

Since the study has not been published or peer-reviewed, it’s challenging to fully evaluate it, Dr. Varady said.

A “major limitation” is that they used just two diet questionnaires to accurately represent people’s typical eating pattern, Dr. Varady said; and the study did not seem to evaluate what kinds of foods people ate.

Dr. Dariush Mozaffarian, a cardiologist and professor of medicine at Tufts University, called the study “very problematic.” The eight-hour eating group may have included many people who were very busy, or faced other challenges that forced them to miss meals or eat erratically, he said.

The group also could have included people who were already in poor health — those with eating disorders or illness that reduced their appetite, for instance, which may have resulted in them eating during a shorter window, said Satchidananda Panda, a professor at the Salk Institute for Biological Studies in San Diego.

And if intermittent fasting is really harmful, it’s not clear why that might be. Dr. Zhong said that his study was not designed to answer that question.

What to Know About Intermittent Fasting (New York Times)

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There is only one correct response to the dozens of recent news reports and articles written in the past few days claiming that time-restricted dieting (compressing eating into eight or so hours each day) leads to a 91% increase in fatal heart attacks: ignore it.

These articles are based on a recently released American Heart Association report. The research behind the claim is a 2003-2018 self-report dietary recall survey project. The comparison groups this report was based on were created by dividing those who responded to at least two surveys in the first year of the study. The assumption was made that the recall information was accurate and remained valid for years.

There are several methodological and statistical reasons why the claims in this report are exceptionally weak. I won’t go into them here but I believe reporting and titling the article and press releases as they did is an irresponsible act because the AHA knew full well how the press would respond to it. (These days, many research report titles are written to attract attention; major universities have a research clearinghouse dedicated to that process.)

There is no way to be certain about what, if anything, this report means. One possibility is that the groups created for the analysis reflect the longer term outcomes of people who, in 2003, were concerned enough about their glucose metabolism and cardiovascular health to adopt what was at that time a fringe diet plan.

I wish it were not true but in today’s reporting environment, it is likely that reportage on health, exercise, and nutritional “research” will be misleading or outright incorrect.

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