Researchers: Artificial Sweeteners Prevent Weight Loss | Hacker News Reader

Researchers: Artificial Sweeteners Prevent Weight Loss

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186 pointsrhapsodic92 comments

Phenylalanine is one of the 20 amino acids required for life as we know it. You are exposed to many times more phenylalanine when you eat high-protein foods compared to an entire 12 pack of diet soda.

Phenylketonurics have to track their phenylalanine consumption, so there are several easy-to-use look-up tables for the amount of phenylalanine in various foods (1).

Diet soda (2) is a rounding error compared to soy, legumes, and meats. Show me a healthy diet without soy, cheese, whole grains, eggs, or legumes and I'll show you someone who's trying too hard to show me something.

(1) https://www.healthaliciousness.com/articles/high-phenylalani...

(2) http://static.diabetesselfmanagement.com/pdfs/DSM0310_012.pd...

Arent amino acids metabolised very differently when taken in isolation from other amino acids? I recall reading that Arginine and Lysine compete for metabolic resources in some way- which is why Lysine capsules are often prescribed for cold sores- for example.

The article just states that the researchers suspected a mechanism of action that involves phenylalanine, but the experiment doesn't actually say anything about what the actual mechanism is. Anyway, aspartame isn't even phenylalanine or anything else that can be found in nature.

Aspartame is composed of aspartate, phenylalanine (two amino acids) and a methyl group.

After you ingest it, it's easily broken down. What your body actually absorbs are the component parts, all of which are ubiquitous in nature.

Forgive my ignorance, but it's not like that methyl group just becomes a free radical, right? Does it stick to either the aspartate or the phenylalanine, and if so, wouldn't that potentially change the body's reaction?

From a quick google search, it appears the methyl group gets converted to methanol.

Which we all know has no ill effects whatsoever.

In very high quantities, yeah, it's bad. Just like everything, including water and oxygen.

In small amounts, your body can handle methanol just fine. Which is fortunate, because it's present in many foods at much higher levels than what you'd get from drinking a can of Diet Coke.

The methyl ester is converted to the free acid and methanol, which you further metabolize into formic acid.

Methyl esters can be readily hydrolyzed (split by water) in an acidic environment. The stomach would be ideal.

Related thought: Before I switched majors to CS, I was taking pre-med classes. I remember my anatomy and physiology professor telling us that the pancreas produces insulin the moment the tongue tastes something sweet. One of my fears is that these "diet" sodas are causing the drinkers' bodies to release insulin needlessly; in other words, lots of insulin in the bloodstream but no sugar to digest. I wonder if this could lead to insulin resistance and diabetes.

The article hints at this [1], but I haven't researched the issue very deeply. I'd be curious if other HNers know something about this.

[1] "We previously showed [this enzyme] can prevent obesity, diabetes and metabolic syndrome [a disease characterized by a combination of obesity, high blood pressure, a metabolic disorder and insulin resistence]. So, we think that aspartame might not work because, even as it is substituting for sugar, it blocks the beneficial aspects of IAP."

It might be interesting to get a blood glucose monitor and see if someone's blood sugar level changes after drinking a diet soda.

It's worth noting that diabetics often do this almost as a matter of course. If diet soda were spiking diabetic people's insulin, they would almost certainly know.

Some of the most avoid consumers of diet soda I've known are diabetics who checked their blood sugar multiple times a day at least.

Avid|Avoid makes for a pretty big difference here :-)

Avid is what I meant. My cell phone keyboard apparently disagreed. ;)

I browsed the research on this some time ago. From what I remember the sweet taste is not enough, as some sweeteners were tested and didn't produce the insulin spike. There was only weak evidence for one of the sweeteners causing a similar effect when tested.

If I remember correctly, Aspartame didn't cause the spike. The problem is that with most diet sodas they won't tell you which sweeteners they use exactly, and in which proportions.

Actually there's more evidence for that happening in the lower intestine which can "taste" sweet things.

Recent studies have shown that this receptor is also expressed in the extragustatory system, including the gastrointestinal tract, pancreatic β-cells, and glucose-responsive neurons in the brain. In the intestine, the sweet taste receptor regulates secretion of incretin hormones and glucose uptake from the lumen. In β-cells, activation of the sweet taste receptor leads to stimulation of insulin secretion. Collectively, the sweet taste receptor plays an important role in recognition and metabolism of energy sources in the body. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3221019/

Also check out https://www.scientificamerican.com/article/your-intestines-c...

Sidebar: I know calories in / calories out vs diets that restrict food groups (e.g. Carbs) is a holy war but there's a whole wealth of info now that supports avoiding foods that cause an insulin response (which starts up fat storage mode). That might not be healthy for everyone but I've experienced first hand how effective it can be.

Your body also releases insulin when you eat red meat. i.e., red meat is as insulinogenic as white sugar. It may not raise blood sugar levels as much, certainly, but it does raise insulin.

Nit: These two statements are inconsistent:

red meat is as insulinogenic as white sugar.

It may not raise blood sugar levels as much, certainly

It would be more appropriate to rewrite the first as "red meat is also insulinogenic"

They seem to work hard to hint that aspartame can prevent weight loss, but are there actually any studies that show that? There are plenty that show that it has the same effect as drinking water.

https://www.ncbi.nlm.nih.gov/pubmed/12324283

https://www.ncbi.nlm.nih.gov/pubmed/2349932

https://www.ncbi.nlm.nih.gov/pubmed/7146134

https://www.ncbi.nlm.nih.gov/pubmed/20303371

https://www.ncbi.nlm.nih.gov/pubmed/9022524

https://www.ncbi.nlm.nih.gov/pubmed/2178391

And the same for rats

https://www.ncbi.nlm.nih.gov/pubmed/11890951

https://www.ncbi.nlm.nih.gov/pubmed/3190217

https://www.ncbi.nlm.nih.gov/pubmed/15159141

edit Found an overview of the evidence for: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2892765/

In the paper they list two studies.

Stellman et al. 1988 : http://www.sciencedirect.com/science/article/pii/00917435869...

Fowler et al. 2008 : https://www.ncbi.nlm.nih.gov/pubmed/18535548

From the abstract [0]: "Conclusions: Endogenous IAP’s protective effects in regard to the metabolic syndrome may be inhibited by PHE, a metabolite of aspartame, perhaps explaining the lack of expected weight loss and metabolic improvements associated with diet drinks."

Can someone explain to me what I'm missing here? What is the "expected weight loss," and what are the expected "metabolic improvements associated with diet drinks"? As far as I'm concerned, one should expect neither metabolic improvements nor weight loss simply from consuming diet soda.

[0] http://www.nrcresearchpress.com/doi/abs/10.1139/apnm-2016-03...

edit: forgot footnote link

I would assume this means substituting artificially sweetened for sugar sweetened drinks.

the title we've been given and the abstract you just quoted fits with my prior that the sugar industry pays for such studies. after all it's obvious that someone who drinks diet sodas isn't getting more Calories than on the packaging, whereas if they drank sugared drinks it would be a huge source.

maybe water would be better as far as "expected weight loss" but it's obviously false that diet soda can prevent weight loss. (unless it takes away a person's will to exercise and takes away a person's ability to make correct calorie-related choices.) If someone is active and eating less than they're using, or exercising heavily and especially building muscle, it's obvious that drinking any amount of diet soda won't inhibit these processes, since people do it all the time.

since you've read and quoted the abstract, could you suggest a title for the mods that's even vaguely true?

" among the groups that received a high-fat diet, the mice that drank the sweetener solution became considerably heavier than those who drank plain water. However, the blood sugar level was higher than normal in all of the mice that received sweetener solution. "

In mice, at least, it seems that the artificial sweetener helped them accumulate more fat than mice who were given water and the same diet. So, aspartame may act like an obesogen[1] in mice.

If you think this is hard to believe and that calories in are calories in, consider diabetics. If untreated, they excrete sugars to the point where they have difficulty maintaining weight on a diet that would make somebody else quite fat. The body's chemistry is complex and, as far as I can tell, not well understood at all, especially when it comes to diet. There seems to be a lot more funding available to develop drugs and procedures to treat illness than there is to optimize (relatively) healthy peoples' diets.

[1]https://en.wikipedia.org/wiki/Obesogen

I still didn't click through but you do not suggest a title. Can you summarize in a neutral way? Maybe "on a high-fat diet, artificial sweeteners may exacerbate weight gain?" Is that fair?

While I was downvoted, 12 hours later Reddit managed to post a much more accurate title (which made its front page). This is Reddit's title:

>Low-calorie sweetener use is independently associated with heavier relative weight, larger waist, and higher prevalence and incidence of abdominal obesity, suggesting that low-calorie sweetener use may not be an effective means of weight control, based on a study of 1,454 participants over 10 years.

This makes total sense to me. It is not fair to summarize this as "prevents weight loss."

High-glycogen metabolism and glucose intolerance (insulin IgE failures really...) would be cut out if you'd had a 'diet' (without aspartame or other ridiculous dimers of phenylalanine.) Delicious irony (and poor showing as literary or legal SEO) ensues.

Most people are bewildered when I tell them I stopped eating sugar. I gave up sweets and sweeteners about two years ago. I cannot say that it has drastically changed my life.

I read one of the many articles on HN about the dangers of sugar and began to ask myself why I felt the need to "treat" myself with sweets? Ultimately I decided that I didn't need it and learning to exercise discipline would likely help me in other areas of my life. I believe it has.

Edit, related articles:

http://well.blogs.nytimes.com/2015/10/27/cutting-sugar-impro...

http://www.theatlantic.com/health/archive/2014/01/the-sugar-...

https://www.fastcompany.com/3050319/lessons-learned/how-givi...

https://www.theguardian.com/society/2016/apr/07/the-sugar-co...

https://www.wired.com/2014/08/what-makes-us-fat

Do you also skip fruits and some veggies or do you mean refined sugar specifically?

I avoid refined sugars and concentrated sweeteners. For me this excludes honey but not 100% unconcentrated fruit juice. I avoid consuming anything with, for example, concentrate grape juice. I still ingest some not insignificant quantity sugar because I don't avoid absolutely everything with sugar in it. I also try not to be a Nazi about it. If a friend really wants me to try something I'll take a bite but I don't make a habit of it. I eat way less sugar than I used to.

Got to love a world where the word fresh has a new meaning g to me; https://www.google.co.uk/amp/civileats.com/2009/05/06/freshl...

What about ketchup for example or BBQ sauce?

I don't eat them. I found that unfortunately I really don't enjoy onion rings any more. Never was a big BBQ sauce fan.

They sell some whole 30 compliant BBQ sauce with no sugar. Has more zing than sweet but tastes amazing.

Ketchup is just sugar. You learn to not miss it when you dump the rest of sugar.

More silly questions. What do you do on Halloween? What would you do if you went to the Cheesecake Factory? I really feel compelled to order cheesecake there :-(

Cheesecake has always been one of my favorites. I don't eat it anymore. I don't miss Halloween candy, the inevitable sugar binge and subsequent crash.

As part of my weight loss, I was already on a track to stop eating as much refined sugar. I found that when I cut down on carbs, I got fewer migraines. I now find that when I eat refined sugars, I'm pretty much guaranteed to get a migraine soon after. Naturally, I've stopped.

I still eat carbs. Probably more than is wise, even. But I absolutely avoid cake, ice cream, candy, and anything else with refined sugar. Yes, it was hard even after I realized the migraine thing, but I've been off it long enough (6 months?) that I no longer crave it like I use to. I put Stevia on my cereal (instead of the sugar I used to put on it) and it's good enough. Other than that, I basically avoid sweets. (Oh, I do drink Diet Mt Dew. So there's that.)

And I'm happier for it, in the end. I don't gain weight from it, I don't feel compelled to eat crappy cheap-ass cake from grocery stores at birthday parties, and (of course) I get fewer and less-severe migraines.

I heartily recommend getting off sugar long-term.

Sound like my diet.

You don't really miss it.

Only annoyance is how many foods sneak in sugar. But I guess that is the whole point of this, to limit what we eat.

Current ban in my diet is sugar and fried stuff, dairy is in the emergency only line..

Link to the paper's publication : http://www.nrcresearchpress.com/doi/abs/10.1139/apnm-2016-03...

Haven't picked up the actual paper yet.

A few problems with the rather sensationalist headline:

1.) As others have said, mice are not people. Mouse metabolism is quite a bit faster than humans, so let's not get too hasty about conclusions. It might be real, but this is suggestive of further research, no more.

2.) The concentration of aspartame in soda is quite low (aspartame is many fold sweeter than sugar). From the article:

"However, aspartame does not block the enzyme directly. It does so through one of its intestinal breakdown products called phenylalanine."

Phenylalanine is a regular old amino acid. I'd have loved to see whether the same effects are recapitulated when you feed high-phenylalanine foods, an alternative test of the hypothesis.

3.) From the article:

"The amount of sweetener solution given to the normal diet group was equivalent to a human drinking three-and-a-half cans of soda a day. For the high-fat group it amounted to the equivalent of two cans."

"In the end, there were hardly any noticeable differences between the two groups of mice that were fed a normal diet."

They go on to mention that there were some possible glucose sensitivity and inflammation differences, but these are hardly conclusive findings. Again, more research, particularly in humans, is warranted.

They also talk about effects on the high-fat mice, which is fine as far as it goes, but again, see number 1.)

All in all, I think deep breath, some caution, and looking at studies that actually involve humans might be warranted before such strong claims are believed.

Here's a few (some open, some closed) that look at aspartame and human diet:

http://www.sciencedirect.com/science/article/pii/00319384909...

https://www.ncbi.nlm.nih.gov/pubmed/24595225

And here's a fascinating article on a new human hormone that has been found the old fashioned way (genetic anomaly) in regulating appetite and metabolism:

http://www.nytimes.com/2016/11/25/opinion/sunday/the-thin-ge...

Neurosurgeon Dr. Russell Blaylock's talk discusses the aspartame / weight-loss issue in detail, and as I recall, he says humans are more sensitive to this effect of aspartame than are mice:

Excitotoxins - The Taste That Kills" https://www.youtube.com/watch?v=tTSvlGniHok

Small edit: I should have made clearer what I meant by metabolic rate. Metabolic rate in terms of heat produced per day increases as a function of mass, so humans have a higher metabolic rate by a good bit than mice. See Kleiber's law:

https://en.wikipedia.org/wiki/Kleiber's_law

However, this relationship scales sub linearly (exponent is ~3/4), so a human is actually more efficient (in terms of converting food to energy for living whose waste then gets radiated as heat). Essentially the concept stands, a mouse's metabolism works differently (apparently generating more heat) than a human's, and we should be careful about how we compare the two.

Minimizing (going from 3-4 cans of diet soda a day to 1-2 a week, on average) my artificial sweetener consumption has made it considerably easier for me to control my appetite.

I've finally been able to lose weight after years of being pretty much stuck. I'm following pretty much the same dietary guidelines (eat lots of fruits and veggies, minimize starches, make sure to get enough fat), but it's working this time because I have so much more control of my appetite. I just don't crave food, especially sweets, the way I used to. And when I do eat poorly, I feel much worse afterwords.

Cutting out diet soda was very hard though, I didn't realize how reliant on the 'sweet' I was until I tried to quit.

I am sure your personal journey has a great deal of value to you, but why do you share this with us? It should be clear that there are thousands of variables at play in your story, and the suggestion that artificial sweetener is responsible for your inability to lose weight seems like a completely unsupported leap.

Websites like this should be forced to actually link to the original study. No credits given that day (and still making money with other peoples content...).

And who would do the forcing?

The audience. By not sharing the content, at least. (Though, that's just a fantasy, admittedly.)

This was a study in mice.

That doesn't mean it's not legit research, but one should put this in perspective. At best this can give hints for further research. It's very far fetched to make statements about effects in humans based on mice studies.

The title here on HN is misleading. The article is not talking about all sorts of sweeteners, it is talking about one specific sweetener — aspartame — in sugar-free products.

There's at least one study which said that artificial sweeteners led you to eat more because your body had the impression to get sugar while having none, leading to compensate by eating more. So there's that.

Sorry I don't have a link to the source but I saw this on HN at some point this year.

Anecdotal evidence here. Throughout my life I have been on diets various time, never because of extreme obesity but like a lot of people in IT, I do not get enough movement and over time gain weight. Thus every 2 years or so I end up going on a diet to lose the weight that I have gained, and in the past I used to mainly drink (sparkling) water when I did this, and always had positive results.

Now I have been trying to diet again but instead of replacing my sugary drinks with the "zero" version of them (coke zero to be specific) I _seem_ to lose weight slower.

Could be a lot more factors in play, but my wife has been suggestion that even those zero drinks have a negative effect on the diet, so she will enjoy this article :-)

Look into whether you might have anterior pelvic tilt (APT), what I call "sitting disease," which causes your hips to tilt forward, making you look like you have a big ol' gut. This is caused by the sitting position (simplified) stretching out your backside and not stretching your frontside. When you have a more neutral posture, your silhouette is much less "heavy" looking. That is, it may not be that you have weight to lose so much as you at a normal weight looks worse than it is.

At any rate, dieting will involve more than switching to coke zero. :)

Oh I was unaware of that, but the way I set when working is far from ergonomically good I fear.

My diet was never just switching my drinks luckily! :-)

As you get older, it is always more difficult to loose weight. Your last diet will (probably) be the most difficult.

No fucking kidding. I'm exhausted by people who say they heard a rumor that maybe aspartame has some secret hidden effect maybe- so it's better to suck down gallons of syrup water we KNOW kills more people than... anything.

Those people and their R tuples of personal biometric data you're asked to normalize! They should just mount scratch retinas and feet, and half of their measurements would be logged without so much as a cellphone lens and IR webcam to bother. If they came with instruments.

So true!

The study found that mice who had aspartame-laced water and ate a high-fat diet (HFD) gained more weight than mice who had pure water but also ate a HFD. All mice on HFD gained weight, though.

It also found that mice who eat a nutritionally balanced diet did not gain more weight whether or not they had aspartame.

We already know that people who are eating HFDs and hoping that diet soda will magically cause them to lose weight are wrong.

But, it is possibly useful to know that aspartame may have a confounding effect when combined with a high-fat diet.

Is it possible/likely that other sweeteners like sucralose and acesulfame potassium do the same thing?

My problem isn't that I choose diet coke for the 'health' benefits. I choose it because its delicious.

You called it right - problem. If you do fasting (no food, just water) for 72h and after fasting put on the table your "delicious" Diet Coke and, let's say V8 veggie juice and try both your body will tell you what's good. You won't be able to drink sweetened drink.

Does anyone know if this also applies to stevia and erythritol?

The effect seems to be caused by a metabolite of aspartame, called PHE. So you could check whether stevia or erythritol produces the same metabolite.

PHE? That was not mentioned in the article. What was mentioned was _phenylalanine_, which is one of the essential amino acids that the human body needs but cannot synthesize itself. We MUST get it from food. It is present in practically all the food (protein) we eat. Particularly good sources of phenylalanine include eggs, chicken, liver, beef, milk, and soybeans.

"Researchers..." "...expert says" "A growing body of evidence..." "How Russia hacked the election" and other ambiguities :

https://en.wikipedia.org/wiki/Weasel_word#Forms

Is this a nod in the direction that its not specifically sugar that is the problem, but the products that have either table sugar or artificial sweeteners in them?

Hopefully these results can be put to a good use in hospital, where extreme weight loss is a problem for many diseases

Any chance this applies to erythritol, xylitol, or Splenda?

https://www.sciencedaily.com/releases/2007/08/070820175426.h...

maybe?

Aspartame contains phenylalanine (the agent in this study that causes the weight loss problem). So every packet of Equal/aspartame displays a clear warning to phenylkenonurics (those who can't digest phenylalanine). No other sweeter bears this warning, and so, should contain no phenylalanine, and will not pose the same threat (to phenylketonurics or dieters).

I'd like to see them explain how this defies thermodynamics. If you aren't ingesting the food energy you simply can't get fat from it.

Specifically I'd like to see this reproduced in humans.

If I read the article right, it's not that you get fat from the aspartame (which the body can't extract any energy from), but that aspartame blocks IAP, which is thought to work against the detrimental health effects of a high-fat diet.

They also noted that blood-sugar levels for the aspartame-consuming mice where higher for both types of diets.

The body is not a steam machine. It doesn't burn energy at the same rate all the time, and what we input into our bodies can affect that rate.

The body is not a simple thermodynamic equation unfortunately :(

Of course it is. Energy input must balance energy output and net changes in storage. What isn't simple is that we don't have the ability to merely will ourselves to eat less. We are not as much in control over our bodies and our consciousnesses as we'd like to believe.

We also don't have the ability (or understanding) to control the conversion of energy-in-food into energy-our-body-can-use + energy-our-body-can-store + waste-products. Food is not gasoline, and our bodies are not combustion engines.

Even that's a bad analogy; gasoline's quality and impurities can vary quite a bit, which effects how much energy an engine can extract from it, and engine efficiency can also vary greatly. Still, our bodies are much more complex.

I'm more inclined to report reported differences to bad reporting of inputs. How many studies are conducted under controlled conditions? People lie about everything all the time, especially to themselves.

So?. It doesn't change the fact that the body literally cannot produce energy out of nothing. If you eat less you WILL lose weight.

Yeah but it's not clear where that weight will come from, or how much it will be.

There are a lot of mechanisms involved in the relationship between eating food and getting fat. One that I often think of as a fatal flaw in many weight-loss diets is that different foods have varying effects on satisfaction and hunger — some foods make you want to keep eating.

If that's were true, it would be impossible for humans and other organism to regulate how much fat and weight they have because it's nearly impossible to balance the energy budget.

So, there's more than just thermodynamic at play here.

You've always got blood sugars at some level.

If you put something sweet into your mouth (real sugar or fake) you're more likely to a) produce insulin and start metabolising those blood sugars, and b) have a 'low blood sugar' feeling and want to eat something :)

Edited for typo

I don't understand why so many people have difficulty accepting that the chemical environment can mediate appetite, and appetite is a key driver of food consumption. Thermodynamics holds. What doesn't hold is the idea that you exist as a consciousness independent of chemical inputs.

But what you're saying sounds to me very different from what most people in this thread are saying. You're saying, if I understand correctly, that eating stuff with aspartame will make you eat more (what happens if you have the self control to either not do that, or eat something like a carrot that has very little calories ?).

Most people in the thread here seem to be saying your body will find a way to use the same amount of energy, and store the same amount of energy, despite the energy intake being different.

Anecdotally, I've lost over 10 kg while not caring about aspartame intake (in fact I think it probably went up).

More that aspartame fooled no GI ever into thinking its job was done than that it makes you hungrier. The alkaline phosphatase blocking from it is also hampering phosphate metabolism you might've been using to switch gears, including regulating pH and coexistence with gut flora (detoxifying oligosaccharides etc.) Nice anecdotal going (if it was low density tissue; I should joke 'you uploaded your brain, what did you expect.')

What you missed out on is feedback loops that affect your basal metabolism. So: eat less, your body decides it is starving and reduces your basal metabolism, you continue to eat less (better-than average willpower!), and... you gain weight.

I'm a physicist, and I roll my eyes whenever anyone starts up with simplistic arguments about humans, food, and thermodynamics. Thermodynamics holds, but the system doesn't work the way you think it does.

Can your body just "reduce your basal metabolism"? Where are the energy savings? Is your body temperature lowered? I'm skeptical of the idea that differences in "metabolism" can account for different results arising from the same energy inputs.

Yes, your body temperature can be lowered, somewhat. Your temperature actually varies over a pretty wide range all of the time, with daily cycles and in response with your activities and things like fighting infections. But your average temperature can trend higher or lower, corresponding to a higher or lower basal metabolism.

Other things that can happen when your metabolism slows down are that you get tired more often and more easily, your thought processes slow down, you sleep more. This happens to everyone as they age, and it can also happen from chronic stress, calorie restriction sufficient to trigger 'starvation mode', and anything else that causes your body to try to conserve energy for survival.

What can be done to boost basal metabolism? A safer DNP? The current approach, diet and exercise, although it may work in individual cases, is not effective at the scale of public health.

Why, yes, it's a typical confounding situation with exercise and diets. As you probably know, it's difficult to do calorimetry on humans, but if I recall correctly it is partly lowered heat generation (which doesn't necessarily change the core temperature you measure with a thermometer) and moving around less.

There's nothing in the article that claims to defy thermodynamics. Consider this: anything you ingest can either be 1) absorbed by the body or 2) pass right through you. This is determined by the digestive processes occurring in your body.

If I feed you a bucket of pure sugar it will be metabolized differently than if I put the equivalent amount of sugar in non-digestible plastic pellets and had you swallow the pellets instead. Hence, it is obvious that weight gain and loss depends on more than just what you eat, it also depends on how your body digests what you eat.

I love how armchair physicists love to repeat this thermodynamics claim as if it's some kind of revelation or even remotely relevant to nutrition science, when a growing body of research is showing that the body's metabolic processes affect weight gain/loss in ways far more complex than originally thought.

For example, studies have shown that gut bacteria can have an effect on fat absorption and hence how many calories are extracted from the food you eat. This means that two people, eating the exact same thing, may absorb different amount of calories from it, and hence may gain/lose weight differently.

Thermodynamics is completely irrelevant here. It tells us nothing meaningful at all.

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