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Dietary Carbohydrates Impair Healthspan and Promote Mortality

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Re: Dietary Carbohydrates Impair Healthspan and Promote Mortality

#101

Post by guelo »

cup-of-tea wrote: post #35

I've read a lot of, often conflicting, dietry guidance. I have realised one very important thing: humans will very easily accept that something they enjoy is bad for them (see fat, sex etc.) So listening to what people say is bad for them is stupid. Instead I have taken a simpler approach: I observe the lifestyles of people who are healthy and live a long time. I have observed that eating simply "good, old-fashioned"…

That's survivor bias. You're missing all the people that died eating fat and carbs at a statistically higher rate than those who did not.

Re: Dietary Carbohydrates Impair Healthspan and Promote Mortality

#102

Post by fasteo »

X86BSD wrote: post #53
philfrasty wrote: post #31

Earlier quoted context omitted.

„no carbohydrate intake at all for half a day before“ no way your body was in ketosis.

It takes about a week of < 20g/carbs a day for the body to go into ketosis. This is born out by buying keto strips and testing your urine.

A little known fact is that you can induce ketosis while eating carbs. The biochemistry here is clear: You get into ketosis when you oversupply acetyl groups to the TCA cycle. Adding MCT (Medium Chain triglycerides) to your diet will do this.

Re: Dietary Carbohydrates Impair Healthspan and Promote Mortality

#103

Post by shepardrtc »

>>> (1)The conversion of D-glucose into metabolic intermediates, namely glycolysis, can be inhibited by compounds like (the highly efficient but rather toxic) 2-deoxy-D-glucose or (the less efficient but completely harmless) D-glucosamine (GlcN). The latter is widely used to treat arthrosis with the questionable claim of inducing cartilage regeneration. Both compounds have been shown to extend C. elegans lifespan (Schulz et al., 2007, Weimer et al., 2014), while only GlcN extends lifespan in rodents (Weimer et al., 2014). Notably, GlcN uptake has been also associated with reduced mortality in a large human cohort (Bell et al., 2012).

So does this mean the glucosamine chondroitin pills I take for my joints will help reduce glucose conversion and extend my lifespan?

Re: Dietary Carbohydrates Impair Healthspan and Promote Mortality

#104

Post by benballjr »

have_faith wrote: post #97
GreaterFool wrote: post #85

Earlier quoted context omitted.

I started a keto diet 2 weeks ago. As far as my research into keto goes eating too much carbs kicks you out of ketosis (duh!) and eating too much protein triggers gluconeogenesis which also kicks you out of ketosis. Which is a shame because I'd be happy to eat fatty steak and fatty pork all the time! Keto guidelines generally say 30g carbs per day and that's what I'm going to stick to (net carbs; I want to eat avocad…

What was your motivation for starting the keto diet?

Not sure what this other guy will say, but for the vast majority of people it is for major weight loss, not necessarily lifestyle or belief that it is a "superior" health approach. This is my experience from Reddit's keto and loseit communities anyway.

Re: Dietary Carbohydrates Impair Healthspan and Promote Mortality

#105

Post by cup-of-tea »

roystonvassey wrote: post #91
cup-of-tea wrote: post #35

I've read a lot of, often conflicting, dietry guidance. I have realised one very important thing: humans will very easily accept that something they enjoy is bad for them (see fat, sex etc.) So listening to what people say is bad for them is stupid. Instead I have taken a simpler approach: I observe the lifestyles of people who are healthy and live a long time. I have observed that eating simply "good, old-fashioned"…

I'm sorry - this is naive advice. Generalized, this would mean that we shouldn't innovate or develop anything new at all (if what's worked previously is the ONLY way it should work). Especially, with something related to diet and nutrition, there is an ever evolving need to alter our habits with the way our lifestyles changed. The kind of life your grandmother led is vastly different than the way you do now. Similarl…

What do you suggest that I do then? Read each contradicting study and alter my habits? Or just do whatever I want and wait until there is some real, true, conclusive evidence that something other than what your grandma ate is better for you? I'll be dead by then. I eat every day. I need to choose what to eat now.

Re: Dietary Carbohydrates Impair Healthspan and Promote Mortality

#106

Post by cup-of-tea »

iridium wrote: post #52
cup-of-tea wrote: post #35

I've read a lot of, often conflicting, dietry guidance. I have realised one very important thing: humans will very easily accept that something they enjoy is bad for them (see fat, sex etc.) So listening to what people say is bad for them is stupid. Instead I have taken a simpler approach: I observe the lifestyles of people who are healthy and live a long time. I have observed that eating simply "good, old-fashioned"…

Selection bias is something worth avoiding in understanding health studies. It’s quite likely that you know about these folks because they had the right genetics to be healthy outliers, and by extension, famous. It’s no different than saying I know x people who didn’t die of lung cancer due to smoking, which doesn’t change the implication that y% of smokers will always get lung cancer, we just haven’t figured out wha…

Well my grandmother wasn't famous. I'm not limiting my experience to famous people, I'm just including them.

Re: Dietary Carbohydrates Impair Healthspan and Promote Mortality

#107

Post by bitexploder »

Dove wrote: post #94
bitexploder wrote: post #60

Earlier quoted context omitted.

Satiation from fat varies per individual. Typically it does not satiate any more than carbs (calorie for calorie) and lead to easy over consumption.

> easy over consumption I heard this for years and years, but it doesn't pass the sniff test for me. Go try to eat a stick of butter. Drink some straight cream. Chew on the fat that comes with your beef roast. Sip sausage grease. Drink straight olive oil. All of these things are hard to do. If I get past two or three hundred calories with any of them, I am workin for it. I have this drink in the morning, 240 calories…

Studies are better than biased self tests. Even self study where you try to apply perceived ratings and controlled calorie measuring is better than a sniff test. Try following the setup for some studies on fat vs. carb satiation and see what you come up with. In my experience on a sustained calorie deficit total calories matters most as long as it isn't a refined sugar causing glycemic spikes. I think fibrous carbs vs refined carbs does have an impact. Otherwise, probably much less.

Re: Dietary Carbohydrates Impair Healthspan and Promote Mortality

#108

Post by bitexploder »

lazerpants wrote: post #93
bitexploder wrote: post #51

Earlier quoted context omitted.

The book The Lore of Running covers this as well. For normal day to day things this is fine. However, it is extremely understudied with minimal evidence it works for everyone. https://www.google.com/amp/s/www.runnersworld.com/newswire/d... It is still unclear, and dubious to claim, that you can operate at 80+ percent VO2 max on hard work outs. Maybe for short workouts or workouts with bursts of activity e.g. basketba…

I wonder if many people have tested VO2 max like this. Anecdotally, I know that I have a very difficult time getting my heart rate over 150 if I don't consume carbs, while I can easily get it 160+ if I've consumed carbs. I don't notice a qualitative difference, except during HIIT exercise, but I believe there is a subtle one based on my heart rate.

I have. I found a cool place that did lactate threshold (via constant blood sampling) Dexa fat scans and VO2 max).

The thing is you can use RPE. We basically mean sustained 4/5 effort (rating of perceived on a scale of 1-5). It's a good enough proxy. VO2 max is also tricky because some people have higher or lower VO2 max but go faster or slower. Higher max != Faster times.

I think the sweet spot for very low carb diets is ultra marathon where you keep your HR around 130-140 anyway, wherein you would use fat anyway. Simple fact is you can't max your power output in an aerobic capacity without carbs. This is not disputed. What we want to know is where the cut off point is in terms of percentage of VO2 max.

Edit: just adding, Noakes talks about ultra performance in his book. It covers everything I saw in that book. He dives deep into the body systems and energy production of the body to suss out the science involved.

Re: Dietary Carbohydrates Impair Healthspan and Promote Mortality

#109

Post by XFrequentist »

fasteo wrote: post #48
XFrequentist wrote: post #37

Earlier quoted context omitted.

Anecdatum, but I play competitive basketball on a very low carbohydrate diet ( necessary seems necessarily false. The missing concept (in the brief quote in your comment) might be "fat adaptation", which takes (in my experience) 2-4 weeks (details: http://www.artandscienceoflowcarb.com/the-art-and-science-of... ) One certainly can fuel activity with carbohydrates, but a fat-adapted person should have no trouble with…

OP here. Fully agree. I do 2-3 keto cycles (5 weeks) per year. Not against keto diet. But note that the context of this study is healthspan and mortality, not athletic performance, weight loss, etc. It was just warning that this study does not warrant that keto diet is good for your health in the long term. The title is a bit misleading.

Fair to say the study results themselves (as opposed to the authors' assertion quoted in the gp) don't really pertain to the health effect of low carb/keto, at all (ie null rather than evidence for or against)?

Re: Dietary Carbohydrates Impair Healthspan and Promote Mortality

#110

Post by XFrequentist »

bitexploder wrote: post #51
XFrequentist wrote: post #37

Earlier quoted context omitted.

Anecdatum, but I play competitive basketball on a very low carbohydrate diet ( necessary seems necessarily false. The missing concept (in the brief quote in your comment) might be "fat adaptation", which takes (in my experience) 2-4 weeks (details: http://www.artandscienceoflowcarb.com/the-art-and-science-of... ) One certainly can fuel activity with carbohydrates, but a fat-adapted person should have no trouble with…

The book The Lore of Running covers this as well. For normal day to day things this is fine. However, it is extremely understudied with minimal evidence it works for everyone. https://www.google.com/amp/s/www.runnersworld.com/newswire/d... It is still unclear, and dubious to claim, that you can operate at 80+ percent VO2 max on hard work outs. Maybe for short workouts or workouts with bursts of activity e.g. basketba…

Great comment, I'm curious about all this too. I'd be interested in more precise data than my own vague n = 1 impressions!

I actually spent a fair bit of time delivering VO2 max tests to athletes (in a previous life as an exercise physiology lab volunteer).

This comment has me wondering if I still know any active researchers in this area, looking for ideas...

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