Fructose in diet expands the surface of the gut and promotes nutrient absorption | Hacker News Reader

Fructose in diet expands the surface of the gut and promotes nutrient absorption

nature.com

239 pointsgmays141 comments

To clarify: The increased nutrient absorption they observed wasn’t actually a good thing. Our stomachs evolved to very efficiently extract as many nutrients as possible from the food we eat, so these nutrients weren’t being wasted. Rather, the excess fructose overwhelmed the normal nutrient breakdown process and resulted in an abnormal nutrient absorption pattern:

> Moderate amounts of fructose — for example, those ingested when consuming fruits — are taken up and broken down by intestinal cells. Excess amounts, such as those that might be ingested after drinking a sugary beverage, overwhelm the intestine’s absorptive capacity and the fructose either ‘leaks’ into the bloodstream to reach the liver intact, or it spills over from the small intestine and reaches the colon

Basically: Too much fructose at once, especially without all of the fiber and structure of fruit to slow it down, ends up in places it shouldn’t because the normal digestive processes can’t keep up. Spilling bursts of fructose into your bloodstream and your liver isn’t great for your body.

Excess Fructose spilling into the colon creates another set of problems as this can do weird things to the microbiome. Ideally the small intestine would be able to handle the fructose and leave the colonic bacteria to feed on the leftover complex carbohydrates, but if you eat too much fructose some of it spills into the colon.

What I don’t understand about these articles is the focus on HFCS: as I understand it, honey contains the same or more fructose per unit as HFCS, but these articles never seem to address whether we observe the same effects with it.

HFCS is common in the American diet; honey much less so.

The reason I find this sort of study annoying is that it can make it seem that sourcing food that replaces HFCS with honey or table sugar (e.g. Mexican Coke instead of American Coke) will make us healthier. But, in fact, it would be better to just reduce the amount of HFCS in the recipes and get used to food not being as sweet.

I just settle on Cola being a dessert and should be consumed as infrequently as ice cream, and not as a daily vice.

Per capita consumption of HFCS = 38lbs.

..... of honey = ~1lb (and that seems high to me, personally)

My point is this: if our takeaway from this is “replace the HFCS in our food with honey/agave nectar/table sugar”, we won’t actually solve the problem of reducing fructose consumption. What has to happen is a general reduction of the total amount of added sugars. Whether this means just using less HFCS or using less of an alternate sugar source is relatively unimportant.

Unrefined foods have qualities that make you slow down on eating. Fiber is one of these, which honey doesn't have, but I'd imagine there might be something else in there... all I know is that moderately-active people can eat as much fruit as they want alongside whatever their protein source is.

Market forces would solve that problem very quickly, considering that HFCS costs $0.26 per pound, versus cheap clover honey at ~$5.00 per pound.

A corn syrup free world would drive the price of nearly every fructose-laden food at least 5x higher, if not much more.

Cane sugar is similar in price to HFCS.

I would say honey vs HFCS is similar. A big reason why HFCS is no good is the raw fructose is easily absorbed (as mentioned) whereas sucrose is a dissacharide that must be broken down (which does not happen as quickly).

The big difference in HFCS vs honey is the quantity that we are exposed to in processed foods. If they replaced all HFCS with honey, I can't imagine it would be very different.

HFCS: 55% fructose, 45% glucose

Sucrose: 50% fructose, 50% glucose

Honey: 50% fructose, 40% glucose, 10% maltose (dissacharide of two glucose molecules).

There are hunter gatherers (hadza, ache, pygmies) that eat substantial amounts of honey without becoming overweight.

If you don't get it, it's in their names – they spend their time hunting and gathering, not sitting around watching TV or on a computer. The extra nutrient absorption may benefit them in that case, as opposed to in a more sedentary/modern lifestyle.

That's not even remotely proven, so please don't present it as fact when it's not.

And your snark of "if you don't get it" is absolutely uncalled for here on HN. It's not appropriate.

> That's not even remotely proven

What is not proven? That people gain weight when they consume more calories than they burn? That hunter/gatherers burn more calories than people sitting at a desk most of the day? That extra nutrient absorption might help active people?

> burn more calories than

https://journals.plos.org/plosone/article?id=10.1371/journal...

“average daily energy expenditure of traditional Hadza foragers was no different than that of Westerners after controlling for body size”

That's an interesting study, thanks!

The health threat is not from being overweight. Obese people can be healthy.

The health threat from fructose is liver damage, and all the knock-on results of a sick liver, what they call Fatty Liver Disease, Metabolic Disorder, or lately Processed Food Disease. It differs little from the cirrhosis alcoholics get.

> Obese people can be healthy.

No, they truly cannot be, at least relative to the equivalent non-obese state. (I assume, of course, a sane definition for the term "obese").

I realize this has somehow (bizarrely) become a controversial issue in the US of late but the mountain of scientific evidence is incredibly clear on this point.

The majority of obese people have other health problems. But, not all. For many, another health problem caused the obesity; they would happily give up both, but do not get the choice. For some, eating little enough to actually lose weight would make them sick.

It is overwhelmingly worse to have metabolic disorder without obesity than to have obesity without metabolic disorder. Many, many non-obese Americans have metabolic disorder. A smaller number are obese without metabolic disorder.

The fact that different, sometimes worse, alternatives exist has no bearing on the factual accuracy of what I said. Obesity is without a doubt unhealthy relative to the equivalent non-obese state. It is a significant risk factor for, and in many cases a direct cause of, an astounding number of other disorders.

While there are plenty of illnesses that obesity can help bring on or worsen, not everybody who is obese suffers from any of them. In the absence of such an illness, an obese person may be as healthy and live as long as, any in their cohort.

As a matter of public health, attention is much better directed to metabolic syndrome and circulatory disease, which are more responsive to interventions. Obesity draws attention because it is easily visible, and because people have attached a moral stigma to it. Blinkered public policy has led to there being overwhelmingly more obese people than the natural rate; fix policy, and the rate would return to its normal level.

I'm skeptical that honey consumption among hunter gatherers would come close to matching a diet with processed foods and hidden sugar, let alone the non-so-hidden sugar. Do you have a source?

(1) https://blogs.scientificamerican.com/food-matters/honey-make...

(2) https://www.angelesinstitute.edu/thenightingale/daily-sugar-...

By (1), 20% of a 2000 cal diet (assumption) would be 400 cal, or 100g sugar. By (2), average US sugar intake is 71.14g/day

Sucrose is rapidly converted into glucose+fructose also.

The general health limit for sugar for a person is approximately one small can of Coke per day or less, with no other added sugar anywhere your diet at all. That’s two or three tablespoons of honey or HFCS.

Replacing HFCS with honey is probably technically better for you, but chances are, if you’re an American, your consumption is probably way beyond that limit, and changing out HFCS for honey or sugar won’t make anywhere near enough of a difference to matter.

Avoiding HFCS is good practice for avoiding sugar, but ultimately you should just focus on limiting added sugar at this point and not worry so much about what kind it is. (Especially if you live in America, where the bread on a Subway footlong sandwich has a third of your daily sugar limit in it.)

ps. Fruit juice should be considered water with added sugar, for the purposes of avoiding sugar. Whole fruit is fine enough, since your body knows how to handle overeating fruit.

> The general health limit for sugar for a person is approximately one small can of Coke per day or less

What about if you are, like most people are, also eating carbohydrates? How does the quantity of carbs being consumed affect this limit of sugar?

If you’re asking “can I have more sugar if I eat less bread?”, no, that’s not really how this works. Eat more whole fruit instead.

ed:

If you're asking "do I have to stop eating carbs", they're releasing these guidelines for normal people on a normal diet that includes carbs. If, instead, you eat an American diet, solve the sugar problem first and worry about the rest once you're past the withdrawal symptoms. You'll have to change your diet enough to avoid the sugar anyways and no point in making that extra-difficult.

What are the withdrawal symptoms?

An insane craving for sugary things. It happened to me with "sodas" which was the only high-sugar thing I was taking.

Irritability, headaches (if you were heavily dosing caffeine through soda and don’t replace it somehow), broken hunger sense and unconscious foraging (“wait, why am I looking in the fridge, I just ate an entire meal”).

If you mean sucrose, say that instead of “sugar”.

The article is about the increased absorption of fructose, not glucose.

Sucrose is 50% fructose and 50% glucose.

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

Exactly.

I.e., the glucose is negligible from a public health standpoint, relatively: what matters is the fructose.

Honey is no different from HFCS or sucrose, from that same place: it, also, has no fiber.

Is there any reason to think absorbing lots of simple glucose or sucrose through your stomach lining is much better than than absorbing lots of fructose? A quick google suggests fructose tends to end up as visceral fat while glucose does the normal glucose thing and causes an insulin spike then ends up as glycogen, but it's not clear to me that either of them are very good compared to getting your glucose slowly from complex carbohydrates.

Well, the study suggests that fructose screws with your intestines in a way that promotes obesity, that glucose does not. Slow glucose is fine except when it isn’t fast enough, so there are definitely circumstances to consider like hard mental or physical labor. I wouldn’t recommend zeroing out all sugars and switching purely to bread. Fruit has been cultivated for thousand of years. It’s generally good for us; yes, it has some fructose; eat whole fruit anyways.

> Is there any reason to think absorbing lots of simple glucose or sucrose through your stomach lining is much better than than absorbing lots of fructose?

A better question is if there's any reason not to. You should never blindly assume that biological research on one chemical translates to another. Seemingly small structural differences often (but don't always!) result in wildly different chemical properties. Additionally, biological pathways are incredibly (almost unimaginably) complex.

Well, yes - we already have good alternatives to eating pure simple sugars, whether they're fructose or glucose. One good one is absorbing glucose slowly by breaking down complex carbohydrates, by eating low-GI foods.

In this case, there's not a binary choice between fructose or glucose. You don't have to eat either as 100% of a diet, you can mix and match. Whether there's a reason not to eat pure glucose is not a better question health-wise, it's a much worse question than "should I intentionally eat either fructose or glucose as a large part of my energy intake?"

Absorbing a large amount of glucose at once may be quite bad, but does not cause liver disease.

In particular, large excursions of blood sugar and insulin can cause down-regulation of insulin receptors resulting in insulin resistance, called type-2 diabetes. (BTW, some people can treat this with cinnamon. For others, enough cinnamon would cause even worse problems.)

You can recover from type-2 diabetes in reasonable time by cutting sugar and refined starch (e.g. white flour, white rice) from the diet. It is actually quite easy to do this if you cook for yourself, and surprisingly easy to learn to cook for yourself. It is most fun purely from-scratch, and no more work, and tastier. Start to think of fast-food as not really any sort of food at all.

Many people nowadays seem to find their way to cooking for themselves with an electric pressure cooker, because it is so fast.

It’s common in America to care about whether it’s HFCS or not, but that’s ultimately irrelevant at the quantities of sugar we consume here. Someone else will surely tackle the science-literal answer, so I’m tackling pragmatic-blunt instead.

EDIT: Apparently lots of someone else. I am content with my choice :)

I’m not sure what the correct term is, or what parent should write instead of sugar.

But I feel like parent made a convincing argument that you as a consumer should consider fructose and other sugars as the same thing.

At least until you’ve gotten down to the daily limit, yes.

People in the US might have 50-100g of ‘sugar’ in their non-fat coffee, 50-100g of ‘sugar’ in their smoothie at lunch, and then a ‘sugar’ dessert at night. Whether that’s fructose, glucose, sucrose, honey, HFCS is not important relative to consuming 500% of the daily limit. No food marketing actually says that, so I thought I’d better do so.

This is why juicing is bad, specially if you consume it too quickly. Smoothies are better but eating whole fruit and vegetables is the best.

Is there a difference if you're blending whole pieces of fruit and veg, so you get pulp and all?

That’s probably what he means by smoothie. Though I’m sure some “smoothies” are fruit juice with blended ice.

Yes, somewhat counter-intuitively, because chewing essentially turns fruit into a smoothie!

The difference is the chewing effort and the time taken.

Eating more than two apples makes me tired even thinking about it. I never eat more than one at a time in practice. Similarly with carrots, I'll happily crunch through maybe half of a large carrot, but never a whole one.

Meanwhile, most people can just gulp down four to six apples or carrots worth of juice -- pulp and all -- without feeling immediately satiated.

That's the difference: in juice form we can happily ingest far more food than we would prefer to eat via normal chewing.

Note that it's entirely possible to eat the same amount of apples! It's just exhausting and even unpleasant.

> Meanwhile, most people can just gulp down four to six apples or carrots worth of juice -- pulp and all -- without feeling immediately satiated. > That's the difference: in juice form we can happily ingest far more food than we would prefer to eat via normal chewing.

I wish people would apply this logic to things like olive oil where a tablespoon contains about 20 pressed olives and about 120 calories. It's one of the easiest way to eat hundreds of extra calories more than you should and lots of recipes suggest using a lot of it for frying and dressings.

I think the common encouragement of "but you need fat, it's healthy fat and it's part of the Mediterranean Diet!" is a weird dietary blindspot when the goal is calorie reduction and fat deficiencies aren't the problem. It feel like it's only quite recently that fruit juices are being discouraged and that was a blindspot too.

I don't advocate that there's some magic to a "whole food" diet except that not eating pressed, blended etc. stuff is a decent rule of thumb to slowing down much you can eat in one sitting.

Olives are delicious, and I can eat twenty in seconds…

Would you eat sixty olives plus a meal though? I see celebrity chefs free pouring way more than a tablespoon per serving in recipes all the time.

Aside from pesto I don’t use more than a Tbsp per serving- I suppose I am out of touch with celebrity chef cooking.

Most of it ends up in the pan and plate, though

There was an experiment conducted with three groups of rats. The first got only fed carbohydrates and gained weight. The second ate only protein and lost weight. The third ate fat exclusively, their weight stayed the same.

[citation needed]

Sorry, I don't mean to be snarky, but you can't just make baseless claims and expect others to believe them. It's far easier to make claims than to verify them so there's a significant asymmetry at play here.

Yeah, you are absolutely correct. Sadly i don't have a link at hand :(

Beware of translating rat results to humans, though.

We can eat very high carb or very high fat diet for quite some time, but we very definitely cannot eat very high protein diet without getting seriously, potentially fatally sick within weeks.

Protein poisoning is a thing in humans!

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

As that wikipedia page lays out, this is really a fat deficiency issue. Protein poisoning isn't really an accurate term for the condition.

I would highly advise against that! Protein metabolism creates acidic byproducts. Your bloods ph must stay the same no matter what. If you don't counter those, your body will take calcium from your bones to level it. A diet high in protein needs to be balanced with vegetables and fruit. [edit]Counterintuitively even sour fruit is metabolized basically. The most alkaline food spinach is not without pitfalls though. High consumption over time will net you kidney stones.[/edit]

Thank you, for bringing that to my attention, just read it.

And for some personal anecdata (ie worthless): i eat a handfull of walnuts, one brazil nut and a handfull of almonds each morning. Additionally i down my bulky vitamin D supplement with olive oil which i directly pour in my mouth. May be one tablespoon, may be three. Gained two kilos of muscle in the last 6 months.

Good fat is good for you is what I always say (:

The science backs that up[0].

[0]https://www.youtube.com/watch?v=uSrsk6tbnkE&t=90s

> Gained two kilos of muscle in the last 6 months.

But presumably this was coupled with a fairly taxing exercise routine? (Lifting, calisthenics, climbing, or whatever?)

It was coupled with a exercise regimen with less intensity but more volume. Thats why i managed to keep going for 6 months counting. 100/50/75%. 100% means 5x your 10RM (RepMax) for five sets. If you do deadlifts and benches you vary the weight. Since i did calisthenics mostly i did half the reps @ 50% ... It is a powerlifting cycle compressed to one week. Kettlebells are very well suited for this. 32/16/24, 16/8/12 or 8/4/6 for scrawny geeks like me, who learned their lesson and want to train to stay healthy and not destroy their joints.

Anywhere online where I can read about this?

After 100%, do you wait some days and then do... 50%? 100%, 50%, 75% is during a week?

Or one week in between each?

Or is 100%, 50% and 75% on the same day? -- but that'd mean 75 reps, sounds like far too much

It is from a book by Pavel Tsatsouline, Beyond Bodybuilding IIRC i'll check. You do 100% on your first day, 50% on the third and 75% on the fifth, followed by two days of rest. Muscle grows while resting/regenerating.

Ok, 3 times per week, for the same muscle group, and a bit lower weights -- I haven't tried that before, sounds interesting

My memory still works. Ignore the 90s look of the site. The Chapter is called "DeLorme inspired six week hypertrophy cycle". I do seven and then one deload week at 30% of the current load, i think i should reschedule and decrease the load. DuckDuckGo gives plenty of results on forums too.

https://www.dragondoor.com/b31/

https://smile.amazon.com/Beyond-Bodybuilding-Strength-Traini...

Thanks! It didn't occur to me that there're books about strength training, just like there is about software

I'll check out this six/seven weeks DeLorme cycle thing ... Update: now done, seems it's lower weights and many more repetitions, to build more muscle mass (hypertrophy program), rather than strength, and seems it's not that compatible with lots of running and cardio .. maybe not for me then, thanks anyway :-)

I'm wondering if you're very strong then (and maybe don't run that much?), since these specialized programs seems to be for people who lift a lot already

"Calorie reduction" is in general a rather poor goal when the result is overall health, and is overall not very well supported as a method of weight loss (which is only one axis of overall health).

This is a larger blindspot than the calories in oil. It's actually pretty hard to eat 2000 calories a day with olive oil as the main source. Pasta and meat on the other hand are pretty easy.

There's an increasingly large body of evidence that there is 'magic' to 'whole foods,' mainly through the avenue of microbiome health. The human body evolved to handle eating fruit, not diet soda.

Also calories are so dumb. In its most primitive form, we burn food as a proxy for metabolism. Slightly more sophisticated techniques first breakdown the food by its components (sugars/fats)

Calories are not just calories. That level of reduction is pseudoscience to the point where it's not really science.

It's better than nothing, sure, but hair's breadth.

Food is insanely complex and messy. The body's digestive chemistry is messy - a process of soups of enzymes, acids and bases. Metabolism is messy.

Imagine the difference between chewing a stick of celery, a nut, drinking honey and drinking soda.

Mechanically, the breakdown process of these differ wildly. Celery and nuts will be broken down very roughly. Honey is nice and viscous. Soda is lovely and runny.

Now take those mechanically broken down food items and then pass them through a base bath and an acid bath and you'll unlock x% of compounds ready for metabolysis where x will differ wildly thanks also to the weird and wonderful world of solvation chemistry.

THEN those compounds of varying energy richness will get broken down.

The "calories" of an energy dense nut really aren't the same as a fructose-laden drink

What's a better measurement than calories then?

Unfortunately, for energy state of the art is calorimetry for now. But relying on just "energy" or calorimetry is a terrible heuristic for energy uptake or nutrition/dieting.

I am not a nutritionist but I'd probably choose something akin to blood glucose over calories for food consumption.

If I had to go so simple I'd probably optimise for sugar reduction. And after that carbohydrate reduction.

You'll find you can eat a lot of food and food will be filling if you have a pseudo keto diet. You have to work so much harder to get your calories and fats (when not mixed with sugar) is much more satiating.

Do you agree that eating less than 2000 calories a day when your body only needs 2000 calories a day will result in weight loss?

What subgoal would you recommend for overall health when you're very overweight if not calorie reduction? Obviously I'm not saying don't exercise and eating junk is okay as long as it's within 2000 calories.

I personally don't find e.g. 200 calories of olive oil (which could be 10% of your calories for the day) filling at all in say a salad dressing (vs more salad) so skipping it is a simple way to eliminate excessive calories per day if required. Eating fat is fine though as long as you're watching the calories.

> Do you agree that eating less than 2000 calories a day when your body only needs 2000 calories a day will result in weight loss?

The human body's caloric needs are not fixed at some number of calories per day; the human body's caloric needs adapt to inputs. You can lose weight by starving in the short term, but over the long term it is an ~extremely~ ineffective method of weight loss. There's been a lot of research looking at this over the past 10 years, and it is basically unanimous that the calorie defecit model of weight loss doesn't a really work. The number of very overweight people who have returned to and maintained a healthy weight through counting calories is vanishingly small. A good introductory source on this effect is Why Diet's Make us Fat by Susan Aamodt, but a google search will lead you to many studies.

My personal recommendation for improving overall health for very overweight people would be, first off, to focus on a goal of physical capability rather than weight loss. Excessive fat is a hinderance to most physical acitivty, so you will lose weight naturally as you progress. This has the benefit of being a positive goal rather than a negative/mixed one. Many people lose large amounts of weight after getting cancer; few become better boxers.

As for diet, here are some simple rules than I find improve physical capability and promote healthy weight: 1) drink water 2) quit sugar/sweeteners 3) eat when hungry, not for emotional reasons 4) more cooked green vegetables and fish. In my personal experience, rebalancing psychological relationships with sugar/sweetness and chewing/swallowing is much more effective than counting calories.

> As for diet, here are some simple rules than I find improve physical capability and promote healthy weight: 1) drink water 2) quit sugar/sweeteners 3) eat when hungry, not for emotional reasons 4) more cooked green vegetables and fish. In my personal experience, rebalancing psychological relationships with sugar/sweetness and chewing/swallowing is much more effective than counting calories.

I agree with you. All I'm saying is if you're going to follow simple rules like e.g. eat more cooked vegetables, I think skipping or really limiting oils is a good rule too as it's about the most calorific food stuff you can eat and easy to overdo. You could easily eat 200 calories of oil in a salad without really thinking, but not 200 calories of carrot.

I do think most people would benefit from counting calories for at least some part of their life though. I've known friends and family that have been trying to lose weight for years where they couldn't even guess how many calories they eat or roughly what has more calories than what e.g. they'll say a big sandwich is 200 calories, a whole pizza is 400 calories and a bar of chocolate is 100 calories. You don't need to count everything but I don't see how you can ignore calorie counts completely or at least be aware where the big wins are.

Your simple rules have some of this knowledge encoded inside them even if you're not technically counting calories e.g. water has less calories than soft drinks and fruit juice. Same with "eat whole foods". I assume your "green vegetables" rule is encoding something about avoiding potatoes too, not that non-green is somehow bad by itself?

More anecdotes but I've never seen the problem with sweeteners. I wish they weren't demonised by some people who then use sugar with x10 the calories instead.

Calories are only a single axis within the extremely complicated question that is food quality. It is quite difficult to keep all the variables in one's conscious mind when deciding what to eat. Humans luckily have a very useful set of biofeedback mechanisms that effortless tell you if food is healthy or not, but most people ignore these systems by eating mindlessly and have damaged these systems through poor diet.

The goals of my simple rules have nothing to do with calories; that calorie reduction might pop out if you are overeating is simply a happy side effect of mindful eating (rule 3) and avoiding foods that disrupt the body's feedback systens (rules 1 and 2). Artifical sweeteners are especially dangerous because by weakening the connection between 'sweetness' and 'energy density' they tend to induce people to eat more calories than they otherwise would [1]. If you are trying to count calories while feeding your sweet tooth with splenda you are probably doing yourself a disservice by fighting against human biology. It is better to simply not feed the sweet tooth at all and allow biology to work for you.

I'm really not sure what a 'big win' in calorie counting even is. One of my friends used to eat glorified carboard mixed with artifical sweeteners so she could 'enjoy' the experience of eating while not conusming calories. I think this was a 'big win' for her, but she didn't lose weight. It was an unhealthy behavior.

The green vegetables rule is about eating more green vegetables. They're good for you. High quality vegetables contain important micronutrients. You should cook them because fire is what allowed early apes to stop spending their entire day chewing and develop civilization. One of the problems with the oil prohibition is that it discourages people from eating sauteed vegetables, which are probably one of the best things you can eat. If you are ditching sauteed vegetables for 100 calorie bags of Doritos because you are afraid of olive oil you are probably not living the healthiest possible lifestyle.

[1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3198517/

> Humans luckily have a very useful set of biofeedback mechanisms that effortless tell you if food is healthy or not, but most people ignore these systems by eating mindlessly and have damaged these systems through poor diet.

Why do unhealthy things taste great then? Why would our natural biofeedback be well tuned to modern lifestyles where an abundance of food is the new norm?

> I'm really not sure what a 'big win' in calorie counting even is.

I mean getting people to realise what surprise foods they're eating that are wiping out their calorie target for the day so they can replace these foods with something more healthy e.g. people drinking 1000 calories of coffee drinks or 2000 calorie pizzas and not realising how many calories they're consuming are never going to lose weight.

> The green vegetables rule is about eating more green vegetables.

Why? So no sweet or white potato, eggplant, carrot, red peppers, cauliflower, tomato, beetroot, red cabbage?

> One of the problems with the oil prohibition is that it discourages people from eating sauteed vegetables, which are probably one of the best things you can eat.

I'm not saying never use oil but you can fry without oil, bake, boil, steam, slow cook, pressure cook and microwave. You don't need oil to cook lots of things. Why not deep fry if you shouldn't be concerned with oil and rely on biofeedback?

> Why do unhealthy things taste great

Taste is only one component of the feedback system. The other ones are more important honestly. The toungue is easily tricked by sweetness, which pervades almost all easily obtainable foods in this country.

If you quit sugar and sweeteners for a few months, you will be amazed how sweet everything tastes, and you probably won't want to eat much of it.

> people ... not realising how many calories they're consuming are never going to lose weight.

This is not true. You can lose weight without thinking about calories at all. There are other methods. Of course gorging yourself on pizza and sweet drinks is never going to help you, but people doing that are generally not serious about losing weight.

> Why? So no sweet or white potato, eggplant, carrot, red peppers, cauliflower, tomato, beetroot, red cabbage?

I have literally no idea how you are arriving at this interpretation of the rule. "More green vegetables" does not mean "no beets". It's a simple rule of thumb to get people to eat more vegetables with high mineral and low carbohydrate content. It's far from an exclusive list of all good vegetables, but that list is too high word count for simple rules. Potato probably shouldn't be included in this category as it is a culinary starch and you shouldn't trick yourself into thinking french fries with ketchup are vegetables. But that doesn't mean potato is banned.

> Why not deep fry

There is nothing intrinsically wrong with deep frying. If you listen to your body, you probably will realize you don't actually want that much deep fried food, but in moderation it is fine. The key is to have a properly tuned feedback system and to actually listen to it. Eating slowly with attention while avoiding sugar and sweeteners will probably get it fixed up in a few months unless you have a genetic condition.

Also, chewing and saliva (specifically the enzyme, amylase) combine to start breaking down more complex fibers and sugars before they reach the absorptive parts of the tract.

should people start spitting into their smoothies before drinking them?

Thought-provoking, but maybe yes. Put about half a dozen spoons of spit into the smoothie, then stir and leave for ten minutes.

You end up comparing whole fruits to “juice form”.

I’m not sure if that’s a typo, as the question is related to the difference between whole fruits and smoothies, and that’s also how your argument starts out.

Chewing also elicits the release of enzymes in the mouth and gut and also starts a hormonal cascade that prepares the digestive track to process the food. https://www.yourhormones.info/hormones/gastrin/ https://www.gastrojournal.org/article/S0016-5085(04)01993-6/...

>Our stomachs evolved to very efficiently extract as many nutrients as possible from the food we eat,

I'm pretty sure the stomach just breaks down food with acid it's then passed along to the intestines which absorb the nutrients.

It's even more complicated than that. Some nutrients are absorbed in the stomach. Most are absorbed in the small intestine. Some are absorbed in the large intestine.

Heck, some are even absorbed through the mouth and gums!

This is pretty important information for those finding themselves in the FODMAP division of intestinal issues.

Foods with highest levels of fructose are mostly ready-to-eat cereals.. Always promoted as healthy, is probably one of the worst things you can do in the morning... It will set a roller coaster for the rest of the day

The summary was irritating because it mentioned HFCS over and over as if it is the cause of excessive fructose consumption. But most HFCS is either 42% or 55% fructose, while ordinary table sugar (sucrose) is 50% fructose.

It seems to me that overconsumption of sucrose is just as bad for you as HFCS, in which case focusing attention on HFCS is harmful. People will drink Mexican Coca-Cola made from sucrose and think it is better for them because of this article.

They ran the experiment with HFCS, so that's what they used in the conclusion.

In practice I wouldn't expect different results with a bolus of table sugar. However, they didn't test that so they didn't make any claims about it. Mostly just being scientifically accurate.

Yeah I think so too. But it’s unfortunate because people demonize HFCS for cultural reasons and this article just makes it worse. Like I said, drinking a Mexican coke isn’t going to result in significantly less fructose in your intestine. Even if I do agree that it tastes better. :)

HFCS gets demonized because it's very cheap due to government subsidy. The obesity epidemic was already underway when (for example) Coke switched, but the switch helped keep prices of sweets low and fueled it further than it otherwise may have gone.

Maybe it's demonized because in the US it's added to almost every possible food? Bread, milk, cereal, you name it.

It's remarkable how different pure dextrose/glucose/grape sugar lozenges make you feel than fructose candies.

I wonder why l-glucose has never been used as an artificial zero calorie sweetener.

Edit: expensive is a lame reason. Sugar isn’t the dominant factor in pricing and hasn’t been for quite a while. There’s a huge population of affluent consumers who would gladly pay a large premium for an authentic zero calorie sugar taste.

Because it’s expensive to make since it’s incompatible with normal biological production.

Tagatose can be produced relatively easily and has 38% of the caloric content.

https://en.m.wikipedia.org/wiki/Tagatose

Not only table sugar: as I understand it, these results should be replicable with honey (and maybe agave syrup?) too. It really seems to me that a lot of health articles are systematically deceptive about the relative issues with HFCS vs. other sweeteners.

Honey does have slightly less fructose in it (IIRC ~40%). And it does contain beneficial micronutrients. But mostly it's just as "bad" for you as cane sugar or HFCS.

Table sugar does not "contain" fructose, just like consuming table salt isn't like throwing a chunk of sodium down your throat.

More directly, sucrose consumption isn't likely to result in a buffer overflow of fructose because your body regulates the breakdown of sucrose via sucrase production.

If sucrase production was limited people would be able to easily poison themselves by eating too much sucrose. Sucrose intolerance from sucrase deficiency seems pretty rare though and I’ve never heard that your body regulates the breakdown of sucrose. Seems rather that the body makes how ever much sucrase is necessary to make sure the enzyme is not the limiting factor.

I think to a first order, sucrose really is 50% fructose to the human body.

It's hard to parse out what you're trying to say here. Are you really equating anything less than infinite sucrase to a sucrase deficiency? Not-unlimited does not equal deficient.

>6. Could the real culprit in fatty liver disease be high-fructose corn syrup, not regular table sugar? After all, it says "high-fructose" right on the label.

>Regular table sugar is made up of about 50% fructose, and a common formulation of high-fructose corn syrup (called "HFCS-55") contains 55% fructose. These products are similar enough that there is no evidence of differences in their impact on metabolic health. However, some commercially available formulations of high-fructose corn syrup contain higher proportions of fructose, such as 65% or even higher.21 We do not know whether the health consequences of these products differ from products containing lower concentrations of fructose.

UCSF researchers seem to suggest that this isn't actually relevant

https://sugarscience.ucsf.edu/alternate-views-toxic-truth.ht...

Since both sucrose and HFCS are quickly degraded to fructose and glucose, I think the result would be the same as eating a mixture of straight fructose and glucose. TFA speaks to eating straight fructose.

Undigested sucrose in the large intestine causes bloating, flatulence, diarrhea etc. Doesn't happen in normal circumstances. It's all rapidly broken down into glucose/fructose.

In addition to overall fructose levels, its suggested that the ratio between glucose and fructose levels may be important for determining the changes to the nutrient absorption pattern.

Figure 1 of the linked article illustrates a model by the study authors concerning the effects of glucose vs fructose on gut morphology and nutrient absorption pattern. As described in the caption, fructose up-regulates (ie stimulates) a biochemical pathway that leads to changes in the gut which cause increased nutrient absorption and lipid (ie fat) synthesis, but glucose down-regulates that same pathway.

Put simply, fructose and glucose compete antagonistically to either promote higher nutrient absorption or lower it, respectively. One pushes the lever, the other pulls it, and the ratio will determine who wins. The linked summary article does not, however, state what the relationship between ratio and degree of effect is.

Yea but sucrose is different molecularly; the Glucose and Fructose are bonded whereas HFCS it’s a mixture of the two… so the former the body has to metabolize it while the latter it does not. So calorie intake is higher and fructose and glucose are absorbed faster and at higher amounts.

A. Needs the usual disclaimer "in mice" added to the title.

B. It's not as simple as the title seems to suggest and I like this section for summing up a nutshell "good news, bad news" take on this:

Evidence has emerged5–8 that the small intestine acts as the gatekeeper for the mammalian body against the harmful effects of fructose, the main one being the aberrant accumulation of fat (termed steatosis) in the liver. Moderate amounts of fructose — for example, those ingested when consuming fruits — are taken up and broken down by intestinal cells. Excess amounts, such as those that might be ingested after drinking a sugary beverage, overwhelm the intestine’s absorptive capacity and the fructose either ‘leaks’ into the bloodstream to reach the liver intact, or it spills over from the small intestine and reaches the colon5.

> It's not as simple as the title seems to suggest and I like this section for summing up a nutshell "good news, bad news" take on this:

The paper isn’t suggesting this is good news at all. The observed modifications to nutrient absorption were largely negative.

The intestines don’t actually have a problem absorbing nutrients. The problem is that excess fructose can disrupt how quickly those nutrients are absorbed, which causes problems.

In this case, the increased nutrient absorption isn’t a good thing.

I have a condition that actively interferes with nutrient absorption. It's why I bothered to read this at all.

I’m so tired of this “in mice” meme, it tells us nothing about how accurate the predictions can be made from these experiments. Can everyone just assume “in mice” is the default and in humans the exception? We do experiments in mice because so much is the same between mammals.

We do experiments in mice because they are cheap, most people don't care too much if you kill them and dissect them, it's actually quite hard to get meaningful data from humans and a violation of a bunch of medical ethics stuff to do similar experiments in humans.

I happen to think "in mice" matters. We don't really know how well that translates and I read medical research pieces because I have a serious condition. For me, the stakes are fairly serious. Killing or not killing me is not hypothetical. It's very real.

The title doesn't specify it.

Also a lot of human to mice analog studies have been performed in the past. If you insist all studies be only performed on humans, the progress of science will slow dramatically.

The killing you or not killing you is a bit of a red herring argument. If you're that close to death you should find the best doctors and rely on them than whatever you read on some orange colored website.

No one is demanding they stop doing studies on mice, rather many people want these articles to make very clear if the results of studies are from humans or mice, because the results often don't translate across species.

Maybe bring that up with the authors then? I would assume they would have felt the need to place that in their title if they believed it would be needed.

It's a long standing complaint about mouse studies - but when people add 'in mice' to titles readers care less, so they don't do that. Even nature has clickbait now.

I’m saying it’s pointless information because 99% of studies are done in mice, we should label the studies that are in humans (i.e. the exception). It’s almost certainly safe unless it says otherwise for people to stop writing this pointless meme after every study that ever appears anywhere. If it is really in humans that will be in the title in most cases because it’s surprising information.

Mice/rats are a decent model, you just have to know how to extrapolate:

- toxicity - rats are actually pretty good once you correct for metabolism (divide LD50 by 6). Humans and rats consume lots of xenobiotics due to our versatile diets

- neuroscience, anything below the prefrontal cortex is pretty well conserved between rats and primates

- cancer - kinda garbage. Mice and rats get cancer at the drop of a hat. But if it doesn't give rats cancer, that's a really good indicator of safety

- exercise - generally extrapolates pretty well

The worst is probably things like higher neuroscience, Alzheimers, and diet. Mice in particular are more vulnerable to high fat and high sugar diets than humans. It's fairly easy to induce diabetes in mice, but again, useful in that it increases sensitivity. But also means anti-diabetes drugs may have exaggerated effects.

The food pyramid used in the western world misled people to believe fruit is a necessary component of a diet. It absolutely isn't. Vegetables give you all the dietary components without the high amounts of sugar. And if you eliminate all simple sugars / obvious bad carbs from your diet, then eventually stuff like sauteed carrots / corn, beets, etc. starts to taste 'sweet' to your reset tastebuds.

Produce literally tastes different in the US when compared to other countries. My guess is that these shelf stable varieties which are more bland aren’t used elsewhere.

To say nothing of the fact that modern "fruits" bear little resemblance to the fruit available to us through much of our evolutionary history.

We've bred, selected, and engineered "fruit" for sweetness, size, yield, and color to an enormous extent over the past 500 years or so, with the majority of that acceleration occurring in the last 100.

AND bred the fiber entirely out of, specifically, grapes.

Remarkably, no other fruit lacks fiber.

To be clear, carrots, corn and beets taste sweet because of not-insignificant amounts of simple sugars. Especially cooked.

While that may be true, I don't think most American sugar consumption comes from fruits. I guess if Americans switched to snacking on fruit rather than processed foods, even if we ate the same mass of snack food, it would be good for the average person's diet. There's no need to demonize fruit at this juncture -- maybe later when that is the most unhealthy thing people are eating.

(Personally I'm on a kick-the-dad-bod diet right now -- all I've done is try to eat 2x as much veg each meal, stop drinking, switch most snacking to apples, and put a little quarter cup measure in any bags of snack food I happen to have in the house. Down 13lb since early July on a not terribly fat baseline. For me, fruits have been very helpful as they seem to give a good contribution to satiety, while being less calorically intense than what I was snacking on before.)

This study is about consuming HFCS by itself. My understanding, at least based on the studies referenced in “How Not to Die”, is that the fiber in fruit more than makes up for the high sugar content.

I agree in general, though, that much of the processed food we get in the US is oversweetened or oversalted, and it totally distorts the palate.

Maybe not necessary, but one type of fruit you should probably still consider are berries. Most are pretty low carb but pack a lot of nutrients in them. I'm on a pretty big blackberry kick myself right now (having at least one serving a day).

Even keto diets allow for eating berries in moderation. That's actually how I started getting into eating berries again, when I was doing keto (I'm not currently).

https://www.dietdoctor.com/low-carb/keto/fruits

This is the worst diet advice I've ever read. The problem is not corn, carrots, or beets in any person's diet.

I eat fruit all the time, 2-3 types a day, and I am very strong and physically fit.

Why isn't the increased nutrient absorption offset by decreased appetite and intake? Is there something special about fructose on the demand side as well as the supply side, somehow suppressing normal energy homeostasis?

Your body is going to absorb the nutrients one way or another. High fructose doses are changing how those nutrients are absorbed in ways that aren’t beneficial. You don’t want a rapid spike of fructose absorption pumping unprocessed fructose into your bloodstream, as they observed.

If you don't absorb things too fast, they reach and feed your gut microbes -- which need it. And, you need them.

Appetite is only loosely related to caloric intake.

To give an example, our bodies seem to almost completely ignore liquid calories from sugar.

That is why it is possible to consume a literal 1000 calorie frappuccino and not feel the slightest bit full.

Or compare eating your sugar via gummy bears and via sweet fruit. It's not the calories so much as the amount of roughly solid stuff.

I'm gonna guess because for most of history few people were able to get a massive amount of fructose at once and so there wasn't much evolutionary pressure to select for that.

A bit like an exception nobody thought about while designing the code and so never wrote a handler for.

Because evolution doesn't work to produce good solutions, just good enough ones. For example, your body works out it is in a low oxygen environment by sensing an elevated amount of carbon dioxide, not measuring oxygen levels. As such, it feels painful when you hold your breath, but going into a room with only nitrogen won't make you feel anything, except maybe breathe faster.

Keep this fact in mind as well: "Regular" cane sugar (sucrose) is made of 50% fructose and 50% glucose. Your cells only use the glucose and the fructose has to get metabolized.

Today I learned that, “Sucrose is made up of one molecule of glucose and one molecule of fructose joined together.(Wikipedia)”. A basic fact, but I didn’t know that.

Someone update the Twitter list.

https://www.twitter.com/justsaysinmice

Given that we know the sugar industry paid scientists to blur sugar's role in heart disease [1], and that the whole "eating pyramid" was essentially bought and paid for by industries that just wanted to sell more of their product, how can we ever trust stories like this again?

How can a regular person actually know if articles are "truth" or "paid for truth"

[1] https://www.theguardian.com/society/2016/sep/12/sugar-indust...

why would the sugar industry fund a study that says that HFCS is bad?

I wasn't suggesting the sugar industry is behind this one, but asking the general question of how do we know there isn't someone funding the results they want.

> How can a regular person actually know if articles are "truth" or "paid for truth"

Reading the article might help.

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