Comment by outworlder | Hacker News Reader

Comment by outworlder | Hacker News Reader

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> Fructose can cause fatty liver

It is also a large contributor to rising triglycerides levels and uric acid due to the way it is metabolized. Which in turn contributes to high blood pressure. It also makes Acetyl-CoA, which stimulates lipogenesis.

It is not even true that it is 'blood sugar invisible'. 30-50% of the fructose is converted in glucose and that's visible. The rest won't be available until you start burning fat.

> Yeah, a lot of people have bad diets, but infinitely more pressing is sedentary lifestyles.

No, that's only part of it. And a small part at that. The world didn't suddenly decide to get less active all of a sudden. You can blame some of the sedentary behaviors on societal changes (like suburbs and car dependency in the US), but other countries are getting just as unhealthy, metabolically speaking, and fat.

> The biological reality is that eating a big bowl of frosted flakes is perfectly fine if you follow it up with high amounts of activity.

It has to be really high. We are talking about hours to burn up that bowl of frosted flakes. Spend an hour at a treadmill, calculate the calories you spent. Now check the nearest cereal bar nutritional information. You'll be in for a surprise. You cannot outrun a bad diet.

Diet is most of what needs to be controlled for metabolic health. Resistance training will build muscles, and they are a good buffer since they will eat simple carbs even when you are inactive. Add cardio for cardiovascular health. But, unless you are an athlete or you are active the whole day, you should go easy on the frosted flakes.

>The world didn't suddenly decide to get less active all of a sudden

In many ways, yes it did. There is a shocking decline in active calories in every developed country, and it has been exported to the developing world as well. People are astonishingly lazy, on the average.

Like, Christ, it's so bad that the recommendation to take a brief, slow walk after meals is revolutionary now. Because the average person just waddles to their chair and then "digests". It is astonishing how lazy the average person is in many countries.

>It has to be really high. We are talking about hours to burn up that bowl of frosted flakes.

I love that you declare that I'll be "in for a surprise", as if you're educating me. Hilarious stuff.

In any case, really high is...a bit of an exaggeration. I cycled 30km this morning, at the crack of dawn. A fairly casual, 20km/h or so ride down to the lake and back. That's an estimated 900 calories, or about three bowls of frosted flakes with milk. And the fun thing is that I didn't even eat this morning and did it purely on glucose reserves. This wasn't some athletic thing and was very much a casual "catch the end of summer" thing. Actual athletes absolutely destroy those numbers. People engaged in basic recreational sports destroy those numbers.

And that bike ride is something people would do just getting to and from places in the not to distant past. Where people were constantly moving and doing. Now most of the readers of this comment will have done nothing today beyond moving from seat to seat in various transporters and digestion chambers.

We've all been around someone who is spectacularly lazy who'll tell you about their "metabolism", and who'll jealously jeer when a peer eats without concern and somehow stays healthy. In the vast majority of cases, the latter person is active in their life, and the former person is one of those seat-to-seat people. Being active impacts every facet of your life, and endless choices throughout the day, and it yields an enormous impact on your health.

edit: meant to address the fructose. The fructose converted to glucose does so slowly enough that there is a marginal impact on blood sugar. And the average person consumes multiples more glucose than fructose. Should people consume less fructose (ergo sugar, even if the current admin is trying to healthwash sucrose)? Absolutely. But glucose and simple carbs are the biggest vehicle towards blood sugar and overwhelming glucose reserves.

But there's the exercise paradox, which is that it doesn't work.

https://en.wikipedia.org/wiki/Exercise_paradox

Possibly it works in the extremes, but if so, it's modern and unnatural.

Exercise and basic activity absolutely, unequivocally "works" for removing glucose from blood, which was the foundation of this argument. I'm not giving people diet advice. Indeed, we were talking about frosted flakes, and there are cyclists that have glucose energy drinks -- massive dumps of glucose -- that they consume while riding, and the impact on their blood sugar is utterly negligible. Because activity is an incredible modulator, given that your muscles literally run on glucose, and of course your leg muscles are your largest consumers.

Further, the Hadza study in no universe declared that it requires activity "in the extremes"[1] to alter energy consumption. Not only was their activity not particularly large, they were 112lb men consuming 2,650 calories a day (which is huge for that small of a man. The caloric recommendation for a 112lb active man is 2,000 calories...). The human body is not a magic energy machine that harvest energy from the air, and while it can modulate some things such as "fidgeting" and some other basic processes, the idea that the activity you do doesn't reflect your energy consumption has zero scientific backing.

The exercise paradox is that someone consuming enormous amounts of food but then adding a little exercise routine probably isn't going to achieve much. Which...of course. Control the calories going in is infinitely more effective. But anyone trying to assuage themselves by declaring the exercise paradox for why they're sedentary is cosmically misinformed. The fact that active Hadza men stayed lean on what would normally be considered a massive caloric excess is not the evidence for this belief.

[1] - Paradoxically the study actually entirely contradicts the way you are using it, and I think you might have heard a poor summary of it. The study wasn't that activity doesn't use more calories -- of course it does as the human body isn't a perpetual motion machine -- but rather that going from a lot of activity to an extreme amount of activity starts to plateau and doesn't just linearly move up forever, as the body will start conserving elsewhere. So no, it doesn't require "extreme" exercise, and that is not at all what the study says. And if a 112lb American sedentary man was consuming 2,650 calories a day, they quickly would be significantly more than 112lbs.

You say they did little exercise ("their activity not particularly large", "little exercise routine") and yet they stayed lean, QED. But also you say they didn't achieve much. I don't know what you're saying. I suppose this flailing around is a kind of exercise, and you like exercise.

I know the study said nothing about "extreme exercise", I put that part in to appease you by providing a way in which you might be right.

OK, reading again, you mention "basic activity" at the start, which is reasonable, in contrast with your massively strenuous starvation bike rides. If the thesis is "move around a little in order to accomplish the basic energy expenditure which is as good as it gets," then fair enough.

>You say they did little exercise

LOL, no, I didn't. You seem to have read my comment like your understanding of that study.

Moderately active hunter/gatherers consuming a massive number of calories a day for their size saw plateauing energy consumption, where increasing the activity saw a reduced climb. Again, humans are not perpetual motion machines, and anyone seriously arguing that doing more activity is magically free suffers from self-delusion.

I referred to "little exercise" relative to gluttonous people with a gross calorie excess who then add a little exercise routine and thinks they'll lose weight. They'd be massively more successful cutting calories.

This really isn't difficult to understand.

I edited a conclusion in, maybe we can agree on it.

Incidentally, because I'm puzzled by the "perpetual motion" aspect too, another lever the body can pull is to reduce or increase energy that goes to the immune system and the brain. (But in searching for the Hadza I found https://news.ycombinator.com/item?id=47042766 "Thinking hard burns almost no calories but destroys your next workout", so it's debatable.)

Wear a blood glucose monitor for a month or two. Don't make any changes whatsoever to diet or activity levels for the first 2 weeks.

Then change it up so you are taking a mile or two walk after every meal. Don't change your diet.

Note the difference in blood sugar levels. It won't happen for everyone but the difference just an extremely moderate level of activity makes - especially directly after meals - was actually one of my larger surprises doing exactly the above.

If I am diligent about my 10k steps/day, I find it difficult to put on weight unless I'm eating like total crap. Combine an effort to try to never eat simple carbs with the above walking regimine and most folks are going to drop weight faster than they would ever expect. Quadruple (or more!) true if you also add a GLP-1 to the mix.

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