Very, very interesting, mainly because most of the time, the weight gain from carbonated drinks is said to be linked with the amount of sugar. This study, however, suggests that the mere fact that the beverage is carbonated has noticeable correlation with weight gain.
Would love to find a link to the paper itself, not just the abstract.
ditto x2. I think that might be a cause of concern that we are so dependent on it...
I hate being paranoid about everything, but if I ever find out my Perrier water has been betraying my trust, I'll have to throw it out like I did soda.
I used to drink sparkling water exclusively. When I stopped buying bottled water (to reduce unnecessary expenses), I do seem to recall a slightly easier time of avoiding weight gain. But this really means little, objectively speaking; it's just anecdata.
In addition to testing rats, the study[1] compared five categories of drinks in humans: water, regular carbonated beverage (think soda), diet carbonated beverage (think diet soda), carbonated water and degassed regular carbonated beverage. They measured the release of ghrelin[2], the hormone which essentially tells your body you're hungry.
According to their results, both regular carbonated beverages, diet carbonated beverages and carbonated water resulted in noticeably increased amount of gherlin released (see [1] for the specifics).
So shortly put, it seems sparkling water makes you hungrier. That doesn't necessarily mean it will make you fat, giving in to the feeling of hunger is always up to you, but feeling more hungry sure as hell will make it likely that you will put on more weight.
As far as I can tell, the paper does not include carbonated water as one of the options. It says:
"All rats were provided with standard diet Teklad Global
18% protein (2018SC from Harlan Laboratories). Rats of
each group were supplemented with different beverages:
(i) tap water, (ii) regular degassed CB (DgCB), (iii) regular CB (RCB) and (iv) diet CB (DCB)"
"To extrapolate the study on humans, ghrelin levels were
measured in male subjects after drinking any of the
aforementioned beverages, in addition to CW (no caloric
content, no sugar)."
OK, so they didn't do the rat study where they only changed the carbonation (still vs carbonated water), but later it appears they did this for the human subjects and measured the hormone level. It would be interesting to see a study with only that one variable changed to see actual weight gain in animal and human populations.
Anecdotal, but I changed from carbonated soft drinks to carbonated water and noted a marked difference.
For this model, this hormone is only an indirect effect on weight (through hunger); however, there is also a direct effect that is pretty strong: you are no longer drinking a ton of sugar, which has a noticeable number of calories in and of itself. They aren't saying the weight gain is equivalent, only the hormone release.
Random thought: I'd be curious if results hold up after drinking sparking water regularly and the novelty of it wears off. Like is any of the effect due to an associations in your brain triggered by the carbonation.
Based on the information in the link: "This is due to elevated levels of the hunger hormone ghrelin and thus greater food intake in rats drinking carbonated drinks compared to control rats." It looks like it's the increase in desire to consume as a result of ingesting carbonated beverages that increases the rate of weight gain.
It doesn't seem reasonable to me. Increased pressure would normally come from greater food intake, which should decrease the amount of the hunger hormone. Is this pure speculation, or is there something in the study to back it up?
As the (real) title says, they think it is linked to ghrelin, a neuropeptide associated with hunger. Drinking something carbonated causes more ghrelin release (or less suppression of ghrelin released, actually) than drinking a still beverage. More circulating ghrelin leads to more hunger, which leads to more eating, which leads to weight gain.
The mechanism that allows CO2 to act on ghrelin isn't really clear. They suggest that the bubbles push on the stomach wall, which in turn increases ghrelin release. The whole ghrelin pathway isn't known, but I thought pressure on the stomach walls would suppress, rather than induce ghrelin.
There are a few other odd things too. For the rat experiment, they show weight gain curves (weight vs. time) for four groups: rats drinking a) water b) sugar soda c) degassed sugar soda d) diet soda. As you might expect, rats drinking water end up weighing the least, rats drinking (sugar) soda weigh the most. However, the rats drinking the degassed (sugar) soda weigh significantly less than those receiving diet carbonated soda. They take this as support for their theory, but it seems odd that this effect would totally dominate the actual calories in the sugary soda. Similarly, the carbonated (sugar) soda vs. carbonated (diet) soda groups also aren't different.
This is pure conjecture, as I don't have the links on hand and quick searches don't turn them up, but I saw a study also on HN at one point theorizing that there are pathways for CO2 sequestration as fats/fatty acids in many animal species. (In the terms of the paper that I think I recall, an hypothesis was the increasing levels of atmospheric CO2 due to climate change/industrial outgassing/car exhaust were potentially implicated in the cross-species overweight/obesity epidemic of most species living in human cities.)
I wonder if a follow up study into this surprising ghrelin reaction that increased CO2 pressure in the stomach induces it rather than suppresses it may implicate just that sort of carbon sequestration process?
I'm wondering if there's an insulin response to a carbonated drink?
This sounds very plausible to me. The small intestine, in response to being stretched by food, releases hormones which trigger the production of insulin; this is effectively a preemptive strike against the blood glucose increase which usually occurs from a meal. (The pancreas also releases glucagon in order to ensure that the insulin release does not result in hypoglycaemia, resulting in something called the "Chinese Restaurant Effect" in type 1 diabetics: Eating a large meal can trigger a sharp increase in blood glucose even if the meal in question does not contain any carbohydrates.)
While this particular effect has only been measured with food, not gas, I'd assume the same physiological cause would trigger the same hormonal effect.
Is this true? I once heard that carbonated water is bad for liver, but never found facts to support this (until this paper). Can someone more knowledgeable please comment? People may be destroying their liver and thinking they are doing something good for their health by drinking mineral (carbonated) water...
This paper still doesn't support that conclusion. It's widely agreed (thus far) that carbonation is harmless. Whether or not this study legitimately challenges that is impossible to say without seeing the actual study.
1. dissolved CO2 is in drink. Is drunk.
2. When liquid containing CO2 is in stomach, H2CO3 drops out of solution to CO2 and H2O.
3. The pressure on the stomach cells with CO2 cause them to release Ghrelin
4. When Ghrelin reaches brain, causes hunger sensation
5. Person eats reacting to hunger sensation
Hunger? That's it? OK. Thanks. For me, CW mostly causes me to... drink more CW. Whereas if ghrelin were to do more than cause hunger, that would be rather interesting then.
Oh: "Besides regulating appetite, ghrelin also plays a significant role in regulating the distribution and rate of use of energy.[6]" -wikipedia
I found an IPFS link to the paper. I'm no biochemist, that's for sure.
But to answer your question, it seems that gheberlin is released when pressure is applied. When that hormone hits the brain, the brain interprets it to be "Hunger".
People have been drinking carbonated water for over a hundred years now (maybe even two hundred years actually). If there was a strong link between carbonation and damage to your body we would have seen it by now.
"People have been drinking carbonated water for over a hundred years now (maybe even two hundred years actually)."
There are naturally carbonated springs all over the world. I used to drink from one in Guffey, Colorado when I was a kid - it tasted like a glass of water with two alka-seltzer tablets in it. I think Soda Springs, Colorado is named for one.
Perrier comes from one[1].
People have been drinking carbonated water for more than 100-200 years.
People have been drinking alcohol for thousands of years, if there was a strong link between alcohol and damage to your body we would have seen it by now.
> The study involved groups of male rats who were all fed a standard diet, but given one of four different drinks:
> tap water
> regular degassed (flat) soda
> regular carbonated soda
> diet carbonated soda
EDIT: I found an offhand lower-quality reference [2] that suggests they did test carbonated water:
> Subsequent tests on human volunteers found that those who drank sparkling water at breakfast had ghrelin levels six times higher than those who had still water.
> Rats of each group were supplemented with different beverages: (i) tap water, (ii) regular degassed CB (DgCB), (iii) regular CB (RCB) and (iv) diet CB (DCB)
I think the assumption is that CB and Diet CB, would be something like coke or orange soda or whatever, and that degassed CB would be just coke that was left out so the bubbles dispersed. (Rather than 'soda water' as carbonated water might be called in some places).
The obvious experiment would have been to test tap water vs. carbonated water, which makes one wonder if this study is yet another example of p-hacking. (We were testing this other theory and look at what happened in the dataset, let's make a paper on that!)
That doesn't answer the question though. It's a reasonable inference that "CB" here means "carbonated beverage", and it's reasonable to further infer that these are sweetened carbonated drinks (otherwise why include diet CB?).
The paper is $35. In terms of advice to the public (which maybe it isn't!) it'd be nice if it unequivocally and explicitly covered carbonated water. I drink a lot of carbonated water. It's a recent habit. Thus I'm personally curious.
Reading over the methods the CB in this case is the 'regular' soda and is indeed sweetened. The main result for the rats is that the group given degassed CB gained less weight than the CB with CO2. There is another quote where they look at the reason for the weight gain and argue the following: "The cause of weight increase was probed. Rats, which were given access to RCB or DCB, significantly consumed more food daily, compared to rats which drank water or DgCB (Fig. 2A). This increased food consumption was due to a significant increase in ghrelin levels in the sera of rats on CBs (Fig. 2B). On the other hand, the levels of the satiety hormone, cholecystokinin (CCK), were assessed in these rats as well and the results showed no significant difference among different groups (data not shown)."
They tested carbonated water vs tap water for the human subjects, and Gherlin was about 0.32 for CW compared to 0.5 for tap water (fig 3 in the full paper).
Why can I never actually get sci hub to work? I've even downloaded the data dumps but never figured out how to use their search. Is there a keyword search? All of my searches return "no articles found".
those who drank sparkling water at breakfast had ghrelin levels six times higher than those who had still water
Interesting. Based on a quick wiki (and thus a poorly understood speed read) ghrelin triggers growth hormone release. So if I were to combine carbonated water (no sugar or sugar substitutes) with a healthy diet, would it enhance the positive effects, i.e. muscle growth or tissue repair?
Is growth hormone anabolic in physiological range ? I remember reading about the study suggesting it's not - like those "natural testosterone boosters" - you only get results in the supraphysiological values.
Since I'd have to pay $36 to access the article, I guess I'll just never know if the methods back up the headline. Oh well. A La Croix sounds good about now.
Whenever these `weight gain linked to soda` studies come up, I'm always confused.
I've been told I'm in fantastic shape (>90% in all http://strengthlevel.com/ measurements and under 10% body fat) at the moment, and I used to consume a lot of diet soda every day. At it's worst, I consumed >1 liter a day.
For me it was a caffeine source (since I dislike the taste of coffee and never saw the benefit in acquiring the taste) that helped me focus when I needed to get work done (I did a lot of tweaking around with amounts to make sure it was a marked difference and not just a placebo effect for me) and acted as an appetite suppressant so that I could manage my caloric intake without getting distracted by hunger frequently throughout the day.
I constantly looked at aspartame/stevia/etc research to see what damage I would be doing to myself. While I couldn't really find much in the way of negative health effects (excluding weight gain, which I never noticed a problem with), I ultimately cut off my consumption because of a semi-irrational fear that either information was hidden by soda-corp et al, or that just because of how these chemicals work that there might be bad effects that just haven't been put under rigorous study yet.
As a side note, my metabolism is actually slower than average and I need to eat on average ~10% calories less than any macronutrient calculator says to stay in the shape (low bf + strong) that I enjoy being in.
While I'm in nowhere near as good shape as you, I have similar 'anecdata' findings.
I spent the last few months this year testing this, partly because I was curious about the Tim Ferriss claim that Diet Coke causes you to gain weight. (I actually wanted to test if I could lose weight just from walking & no diet changes.) Even with my two cans of Coke Zero a day, plus sparkling water with ice and a frappuccino most days, I've been losing weight for 4 months. (20.5% bf down to 16.5%.) I did add exercise, but only walking - I increased my steps up to 16000 steps a day for a while, but I'm back to sub-10000/day now. (Pebble Health has been awesome on my Pebble Time Steel.)
Whatever effect carbonated beverages have, at least in my experience, it's easily countered by exercise. Maybe that's not true for everyone, but it seems it's something you can easily test on yourself for a month or two to make your own conclusions.
Yup, at that point I was doing 2 - 2.5 hrs walking a day, though some of it was adding extra steps during my usual day, eg walking a half-mile lap around the shopping mall before going to the cafe. I was able to do it because I'm freelance / flexible hours, and I was determined to complete my experiment.
The usual knock on diet sodas (actually artificial sweeteners in general) is that it wreaks havoc on the gut bacteria, which could have all sorts of adverse effects. Not sure how much evidence of this there is, but weight gain is not the only thing to be on the lookout for.
That makes more sense to me. I imagine one possible side-effect of gut bacteria imbalance could be weight loss for some people, that the side-effects differ for different people.
Right. Just wanted to provide an anecdotal perspective (for those that have similar goals as I) showing that it won't necessarily prevent them from reaching those goals.
I ultimately cut out caffeine completely and have been trying alternative methods of improving my concentration (meditation, etc).
I noticed that while using caffeine, my energy levels would go down pretty hard after the effects wore off, and my tolerance caused it's effect to diminish.
Since quitting cold-turkey, I've noticed more stable energy levels throughout the day (not a surprising conclusion).
I assume you mean "weight gain linked to diet soda" and I think the main thing is that it's still inconclusive. As much faith as we may have in science, I think in terms of dietary studies, most of them have not been able to control a bunch of outside variables. And the food industry also has a shitton of marketing noise to confuse the general populace.
It could actually be having an effect and I could just not be noticing it because there are many other variables in play.
I suppose my comment was inspired by seeing posts about soda and weight gain and seeing comments of anecdotal evidence for people who have cut out diet soda and notice their weight dropping significantly.
I merely wanted to provide an anecdotal data point (however useless scientifically it may be) to try and give a perspective from the other side of things.
ok, but nobody was arguing that they are data points?
The parent was literally saying that he wanted to convey a different story to the ones commonly heard, in order to give a more balanced picture. Nowhere does that suggest anything about data points, just people sharing stories with different view points.
It's good to have a reminder that "anecdata" != real data every now and then, but in cases where you have a poster clearly acknowledging all that, bringing this up seems like little more than an out of place trope.
It's also possible to run marathons, do spinning + yoga classes, eat only raw vegan foods, and die in a car crash. I personally aim for a balance which prioritizes personal enjoyment over absolute longevity-seeking. I don't want to live to be >120, but I also really don't want to spend the 2nd 50% of my life unable to participate in relatively demanding physical activities, like kiteboarding / surfing / mountain biking / >10 mile hikes. I like coffee and tea, and I stay away from soda (diet or otherwise), almost anything with artificial sweeteners, fast food, potato chips, burgers, most things sold at 7-11, more than 2 drinks in a night, etc.
Bodies are complicated I completely agree with you here. I have an extremely bad habit drinking about 2L of diet soda a day (on a good day). I also exercise 4-5 days a week (powerlifting and some light cardio) and am in great shape.
people who read these studies and change their habits to drinking less diet soda, hoping they lose weight, are missing the forest and seeing trees. It's a healthy improvement, but not going to impact their life significantly.
Rephrasing it as 3 cans of soda doesn't make it sound good. 3 cans a day is quite a bit. It might be healthy (or not), but I'm pretty sure 1000 cans/year is well above average for the typical western nation.
I wouldn't be so sure about that. Soda drinkers I've met who are really into it tend to go through a few 12-packs a week. As a kid, I'd play Quake with a 2L of Cherry Coke each night, and I've known others who did the same with Mountain Dew. Live and learn, I suppose.
Well, I specifically called out typical western nations and not just the US. I see a lot of soda drinking in the US and never saw very much in Europe. I don't think American soda consumption is actually typical (or healthy).
Whenever these `weight gain linked to soda` studies come up, I'm always confused.
That seems like the goal, doesn't it?
If sugar is singled as the cause of obesity, the next step will be taxing sugar and not diet sodas. So expect a thick smokescreen around soda. The fact that overhelming difference between beverages with a huge sugar dosage and without doesn't appear in a study is suspicious enough.
Do you mind uploading a shirtless pic (no need to include your face)? I ask not because I don't believe you, but because I do and want to see what that looks like in the wild, esp in a community like HN.
I would instead recommending figuring out the right terms to search for. There are lots of examples online of varying % body fat photos: http://bfy.tw/Bpny (somewhat snarky link provided for comedic effect)
> I've been told I'm in fantastic shape (>90% in all http://strengthlevel.com/ measurements and under 10% body fat) at the moment
Sweet humble brag but considering
> As a side note, my metabolism is actually slower than average and I need to eat on average ~10% calories less than any macronutrient calculator says to stay in the shape (low bf + strong) that I enjoy being in.
You're either a genetic freak or full of it. 90% on all major lifts puts you in the category of amateur competition champion. Go back and run your numbers again, and this time be honest. You're not "strong" at those numbers. You're elite. Which less than 5% of the population fits into. Those kind of people don't browse hacker news. They model for M&F and train for the olympics.
without implying I agree with the particular study, mice are being used to test a lot of chemicals that are then used on humans so I'd say there's a high probability that how mice are affected could be similar to humans.
I don't get it... first it was fats, burgers and pizzas. Then a study came out claiming it's sugar. Now carbonated beverages! What do they want me to do? Eat grass and drink water?
Sample size: 20 people. (Okay what? Are you even trying guys? Releasing something about the the human metabolism with a sample size of 20? Shame on you!)
Concluding a weight gain because Ghrelin levels are raised? What? Do you even science?
Ghrelin in the first place only tells your brain to look for more food because it signals an empty stomach.
Oh please. It's hard to attract funding for studies, it's perfectly reasonable tos tart with a small sample and tehn ask for funding to do a larger study once you have a working hypothesis.
Yes, basically. If you drank water and ate grass with some protein mixed in now and then you'd be much better off. The problem I find with that is it's just painfully boring to do so.
it's complicated, there are many variables involved and doing nutritional research is hard.
the fat study (seven countries) was largely debunked though that doesn't mean all fats in any combination with other macros are good. that sugar is detrimental to your health seems to be a consensus but that doesn't mean other substances can't be bad.
If you're overwhelmed, just remember that the default diet is to eat things that exist in nature at the levels that they exist in nature: Fish, Meat, Fruits, Nuts, Vegetables. This is the default.
Once you start there, you need to look for evidence to switch to eating pizza and burgers and sodas... which there isn't any convincing evidence, just a constant stream of studies about how bad junk food is. It's much less overwhelming to look at it this way I think.
I'm not buying it without a comparison of water to carbonated water.
Its long been understood that soda w/o carbonation isn't palatable because its too sweet and animals stop consuming it. However, when carbonation is present it masks the sweetness which result in increased consumption.
So I think they're probably measuring a secondary effect here.
One of the experiments measures serum ghrelin levels in humans after consuming a fixed volume of liquid; you can directly compare degassed carbonated beverage (DCB) and regular carbonated
beverages (RCB) in their tables.
This controls for the concern you raise above regarding palatability of the beverage, so I don't think that can be a factor there. Critically, there's a statistically significant difference between water and RCB, but not between water and DCB (though the ghrelin level was higher in DCB than water).
From my reading of the paper your concern could certainly be relevant in the rat experiment; I couldn't see any attempt to control for or measure the amount of liquid that the rats consumed, so they could have been drinking less decarbonated beverage.
Soda, is just short for soda pop, which is the sweetened, carbonated water beverage. So soda without the carbonation is just sweetened water. Flat soda is a fairly common term to describe soda that has lots its carbonation.
It's actually pretty interesting that at ~55 weeks, RCB, DCB and DgCB are in very close proximity to one another, then, suddenly, the non-carbonated beverages (DgCB, water) take a huge drop over the next month, with a bit of a stutter on the DCB and a continuous rise on the CB. I wonder if the significance they see in this study is due to an exogenous reaction with the extra CO2 (eg, an environmental factor).
It makes no difference if the water is naturally carbonated or not. Carbonation is caused by dissolved CO2 (in equilibrium with other carbonates) and there is no way for you body to distinguish between "natural" and "unnatural" CO2.
Oh crap. I drink a lot of CB flavored (diet) water, take a med which increases hunger and having weight mgmt issues (also taking metformin for dual-purposes of life extension and weight reduction).
Probably time to switch to diet flavor drops + plain water, and exercise more.
This comment is a reply to many of the commenters here on HN, rather than a direct response to the article.
How do you get to the point of debating the difference between soda vs. diet soda, as if it's a must-have treat and you are "simply" choosing the lesser of two evils? All soda is UNEQUIVOCALLY bad for one's health! You're drinking a cocktail of chemicals that has no nutritional value, and designed to be addictive. Artificial sweeteners are a gimmick to allow us to recuse ourselves from the innate knowledge of what it is healthy. Selecting a supposedly "healthier alternative" is nothing more than a way to grant ourselves asylum from being personally responsible for our choices. We pretend that our "science" is universally proven evidence backed by chemistry and physics, vs. the truth: it's a manmade lie which no enlightened species would tout as being scientifically valid.
The same mental masturbatuion occurs with vaping. "Vaping is better than smoking!" As if inhaling any mind-altering drug is necessary to "get by", and so it must surely be "better" to attach oneself to the "least worst option", rather than kicking the habit entirely. If vaping is "better" than smoking, what is better than vaping? Oh right, not inhaling anything other than the air we evolved to breathe. Your body wasn't made to inhale chemicals not produced in nature; it was also not made to drink soda. The fact that you don't die instantly from consuming such products does not mean they are not harmful.
The excuses many people make regarding their health is... I'm going to call it what it is: completely and utterly _PATHETIC_. As a species we pretend we are intelligent, but a vast percentage (90-95%?) of the population can't even overcome the most primal appetite for fats, sweets and drugs. Our species will never be capable of rightfully calling itself "enlightened" until we drop all desires for this kind of bullshit. If you're playing mind games with yourself to allow you to "cheat just a little" by consuming unhealthy products, while falsely duping yourself into believing your decisions somehow result in an overall net positive "compared to the (unnecessary) alternatives", you're deluding yourself.
Advice to all alien civilizations: avoid us at all costs. Making contact with us cannot possibly be beneficial to you. We'll either bomb you out of fear and ignorance, or bombard you with our capitalist bullshit in order to pull you into our way of living that will ultimately destroy you from the inside out.
What makes this truly disgusting is that people who choose to destroy their bodies - by drinking diet soda, vaping, or eating junk food - are in fact aware that they are lying to themselves. You know that you are making the wrong choices, but opt for the fallacy that somehow you are not in control. Nobody really believes the marketing companies are pushing out. People are just looking for someone else to give them permission to be unhealthy, desperately listening for someone to tell them what they want to hear. People know they are too weak to have self-control, and are looking for a voice to be their scapegoat.
tldr; Diet soda is not "better" than soda laden with unadulterated sugar. It is simply worse than water, and the fluids you would get from fruits, vegetables, and free-range animals and fish. Allow your brain's thought processes to align with your species' natural evolution. Stop using product manufacturers' claims as a scapegoat. Think for yourself, and don't make excuses.
Edit: To those downvoting: do you downvote because my post is too long and you declined to actually read it, or do you refute the facts? I am normally abrasive in general, but what I've said here really is true. Anyone who reads the whole thing, and still downvotes, is someone with their ...
I think people are downvoting it because you are ranting.
A general heuristic that is useful in life is that if someone is foaming at the mouth and shouting, the things they say probably aren't that useful. (And you definitely come across like that. EG someone scanning the text would see "_PATHETIC_", and would assume that the emotional part of your brain has been engaged rather than the rational part).
The use very early on of "All soda is UNEQUIVOCALLY bad for one's health!", probably put a lot of people off. It is trivially hard to refute (any example of any soda providing any health benefit (eg rehydration) proves you wrong), and again makes it seem like you are making illogical, emotional arguments.
The use of "Anyone who reads the whole thing, and still downvotes, is someone with their head in the sand" is a cheap nasty trick that will turn people against you even if they agree with you.
Try waiting until you have calmed down and rewriting it in a better way.
The edit, insulting even further, was useless on my part. If I think that up to 95% of people - and I sincerely believe the percentage to be that high - are incapable of realizing that substituting diet soda and vaping in lieu of sugar soda and smoking cigarettes equates to "healthier choices", I should have expected 95% downvotes.
My mistake, born from a delusion of my own making, is believing that the entirety of the HN crowd magically falls within the <= 5% of people I consider to be legitimately intelligent, capable of thought relying on science that is universally proven to be true rather than manmade speculation based on tomfoolery. Without seeing any replies countering my statements, I can only assume that these people are petty enough to vote with their trigger-happy index finger rather than taking the time to absorb - and perhaps reply to - the points of discussion I have raised.
Aside, meta: Please do not vote on this comment. By upvoting, you'd be granting my ego a reprieve. By downvoting, you'd be proving my point and also feed my ego. Best bet is to abstain, and let bygones be bygones. This could be -10 or +10 and I'd feel validated. Just don't vote; a 0-1 score says more than anything.
Apparently this misspelling gets by the filter that would otherwise have made this post dead-on-arrival...
To the bigger point, replacing something that is very harmful with something that is less harmful is about the best we can do. Baby steps. Puritanical absolutism is about the worst possible approach if you want to get other people to change their behavior.
Also, nicotine, divorced from all the nasty shit you get from inhaling burning plant matter, is not particularly bad for you. https://www.gwern.net/Nicotine
What one can do is reset your body. Consume your own grown stuff and only drink spring water, from a real spring, and see the effect on yourself for 4-6 months. The problem is that there are a lot of people that grew in urban areas and they don't even know what they are missing. Simply put, most urban areas are designed to be efficient and so not good for you.
Naturalistic fallacy. A water filter will do fine and water from a spring can have heavy metals and other chemicals in it that make it significantly worse than city tap water.
Can anyone even figure out what carbonated beverages were used for this study? Was there caffeine in it, etc? Then they say they started with 16 rats but then elsewhere (when it is mentioned at all) they seem to have 4 groups of triplicates. So it looks like 25% of the data floated away. They also don't mention blinding.
Those are the type of basic questions you should ask when you read a paper that will lead you to immediately dismiss something like this in under 20 min.
Studies like these are way too simplistic to conclude anything regarding obesity, in my opinion.
An increase in ghrelin levels was measured, but what about all other other hormone levels that were possibly affected as well? The body is a complex system of thousands of equilibria; if an increase in e.g. testosterone levels (which makes the body burn off fat) was also an effect, this may well offset the effect of increased food consumption -- or even overpower it, causing a weight decline as opposed to a gain.
Whenever there's a study that says X causes Y, there should be a rule that says you have to say by how much. That's a super-important piece of information. The abstract should state it!
If a study says that drinking grapefruit juice shortens your lifespan by a year, then I'll cut out grapefruit juice. If it shortens it by a few hours on average, then even if the study is 100% accurate, it's too small to care about.
Especially in news articles, we tolerate this imprecision with health-related findings but not in other areas. You don't see the news reporting that "avalanche kills some skiers". They'll at least tell you "avalanche kills 1 skier and second skier still missing" (unfortunate) or "avalanche kills as many as 350 skiers" (major tragedy).
The problem is that those estimates are conditional on what variables they put into their statistical model, so they are really usually rather meaningless (not that the mere direction is any more reliable, this can switch too). Maybe you can say:
"A specific carbonated beverage (batch 1234 from supplier X) provided ad lib via a standard rodent water bottle with sipper tube increased weight gain by 10% over the course of 3 months (as they aged 3-6 months) of male sprague dawley rats bred by Harlan USA in 2015, raised two to a cage, fed Z brand rat chow ad lib (10 % fat content), kept on a 12 hr reversed day/night cycle at 18-23 C with relative humidity maintained between 40-60%. Over the course of the study, the rats were removed from the cage only three times a week: for 10 seconds of weighing in the afternoons MWF."
I do not think this study can prove that carbonated soda causes weight gain, let alone obesity. People (and apparently mice) are not all "built" the same. Obese people need more exercise (or just plain movement of the body) than those who have less weight on their bodies, "it's not rocket science".
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[ 4.2 ms ] story [ 210 ms ] threadWould love to find a link to the paper itself, not just the abstract.
I hate being paranoid about everything, but if I ever find out my Perrier water has been betraying my trust, I'll have to throw it out like I did soda.
According to their results, both regular carbonated beverages, diet carbonated beverages and carbonated water resulted in noticeably increased amount of gherlin released (see [1] for the specifics).
So shortly put, it seems sparkling water makes you hungrier. That doesn't necessarily mean it will make you fat, giving in to the feeling of hunger is always up to you, but feeling more hungry sure as hell will make it likely that you will put on more weight.
[1] https://sci-hub.cc/10.1016/j.orcp.2017.02.001
[2] https://en.wikipedia.org/wiki/Ghrelin
"All rats were provided with standard diet Teklad Global 18% protein (2018SC from Harlan Laboratories). Rats of each group were supplemented with different beverages: (i) tap water, (ii) regular degassed CB (DgCB), (iii) regular CB (RCB) and (iv) diet CB (DCB)"
"To extrapolate the study on humans, ghrelin levels were measured in male subjects after drinking any of the aforementioned beverages, in addition to CW (no caloric content, no sugar)."
Anecdotal, but I changed from carbonated soft drinks to carbonated water and noted a marked difference.
I'm wondering if there's an insulin response to a carbonated drink?
The mechanism that allows CO2 to act on ghrelin isn't really clear. They suggest that the bubbles push on the stomach wall, which in turn increases ghrelin release. The whole ghrelin pathway isn't known, but I thought pressure on the stomach walls would suppress, rather than induce ghrelin.
There are a few other odd things too. For the rat experiment, they show weight gain curves (weight vs. time) for four groups: rats drinking a) water b) sugar soda c) degassed sugar soda d) diet soda. As you might expect, rats drinking water end up weighing the least, rats drinking (sugar) soda weigh the most. However, the rats drinking the degassed (sugar) soda weigh significantly less than those receiving diet carbonated soda. They take this as support for their theory, but it seems odd that this effect would totally dominate the actual calories in the sugary soda. Similarly, the carbonated (sugar) soda vs. carbonated (diet) soda groups also aren't different.
I wonder if a follow up study into this surprising ghrelin reaction that increased CO2 pressure in the stomach induces it rather than suppresses it may implicate just that sort of carbon sequestration process?
This sounds very plausible to me. The small intestine, in response to being stretched by food, releases hormones which trigger the production of insulin; this is effectively a preemptive strike against the blood glucose increase which usually occurs from a meal. (The pancreas also releases glucagon in order to ensure that the insulin release does not result in hypoglycaemia, resulting in something called the "Chinese Restaurant Effect" in type 1 diabetics: Eating a large meal can trigger a sharp increase in blood glucose even if the meal in question does not contain any carbohydrates.)
While this particular effect has only been measured with food, not gas, I'd assume the same physiological cause would trigger the same hormonal effect.
Oh: "Besides regulating appetite, ghrelin also plays a significant role in regulating the distribution and rate of use of energy.[6]" -wikipedia
But to answer your question, it seems that gheberlin is released when pressure is applied. When that hormone hits the brain, the brain interprets it to be "Hunger".
The biochemistry sounds rather improbable.
There are naturally carbonated springs all over the world. I used to drink from one in Guffey, Colorado when I was a kid - it tasted like a glass of water with two alka-seltzer tablets in it. I think Soda Springs, Colorado is named for one.
Perrier comes from one[1].
People have been drinking carbonated water for more than 100-200 years.
[1] https://en.wikipedia.org/wiki/Perrier
> The study involved groups of male rats who were all fed a standard diet, but given one of four different drinks:
> tap water
> regular degassed (flat) soda
> regular carbonated soda
> diet carbonated soda
EDIT: I found an offhand lower-quality reference [2] that suggests they did test carbonated water:
> Subsequent tests on human volunteers found that those who drank sparkling water at breakfast had ghrelin levels six times higher than those who had still water.
[1] The only details I could find were at http://www.westerntelegraph.co.uk/families/print/Can_fizzy_w...
[2] http://www.telegraph.co.uk/news/2017/05/15/fizzy-water-could...
> Rats of each group were supplemented with different beverages: (i) tap water, (ii) regular degassed CB (DgCB), (iii) regular CB (RCB) and (iv) diet CB (DCB)
Where CB is carbonated beverages.
I think the assumption is that CB and Diet CB, would be something like coke or orange soda or whatever, and that degassed CB would be just coke that was left out so the bubbles dispersed. (Rather than 'soda water' as carbonated water might be called in some places).
The obvious experiment would have been to test tap water vs. carbonated water, which makes one wonder if this study is yet another example of p-hacking. (We were testing this other theory and look at what happened in the dataset, let's make a paper on that!)
Screenshot (CW = carbonated water):
https://pbs.twimg.com/media/C_-Rcr_UwAASYae.jpg
The paper is $35. In terms of advice to the public (which maybe it isn't!) it'd be nice if it unequivocally and explicitly covered carbonated water. I drink a lot of carbonated water. It's a recent habit. Thus I'm personally curious.
>The paper is $35
It's on sci hub.
Not only that, but they also tested against degassed carbonated beverage, which is clearly stated on the "RESULTS" section of the abstract.
[1] https://news.ycombinator.com/item?id=14352563
[2] https://news.ycombinator.com/item?id=14352725
Interesting. Based on a quick wiki (and thus a poorly understood speed read) ghrelin triggers growth hormone release. So if I were to combine carbonated water (no sugar or sugar substitutes) with a healthy diet, would it enhance the positive effects, i.e. muscle growth or tissue repair?
I used the Unpaywall chrome extension and it wasn't able to show me an unpaid version.
Also helps if you work for a university that pays these rape-quality fees to access what should be public knowledge.
I've been told I'm in fantastic shape (>90% in all http://strengthlevel.com/ measurements and under 10% body fat) at the moment, and I used to consume a lot of diet soda every day. At it's worst, I consumed >1 liter a day.
For me it was a caffeine source (since I dislike the taste of coffee and never saw the benefit in acquiring the taste) that helped me focus when I needed to get work done (I did a lot of tweaking around with amounts to make sure it was a marked difference and not just a placebo effect for me) and acted as an appetite suppressant so that I could manage my caloric intake without getting distracted by hunger frequently throughout the day.
I constantly looked at aspartame/stevia/etc research to see what damage I would be doing to myself. While I couldn't really find much in the way of negative health effects (excluding weight gain, which I never noticed a problem with), I ultimately cut off my consumption because of a semi-irrational fear that either information was hidden by soda-corp et al, or that just because of how these chemicals work that there might be bad effects that just haven't been put under rigorous study yet.
As a side note, my metabolism is actually slower than average and I need to eat on average ~10% calories less than any macronutrient calculator says to stay in the shape (low bf + strong) that I enjoy being in.
I spent the last few months this year testing this, partly because I was curious about the Tim Ferriss claim that Diet Coke causes you to gain weight. (I actually wanted to test if I could lose weight just from walking & no diet changes.) Even with my two cans of Coke Zero a day, plus sparkling water with ice and a frappuccino most days, I've been losing weight for 4 months. (20.5% bf down to 16.5%.) I did add exercise, but only walking - I increased my steps up to 16000 steps a day for a while, but I'm back to sub-10000/day now. (Pebble Health has been awesome on my Pebble Time Steel.)
Whatever effect carbonated beverages have, at least in my experience, it's easily countered by exercise. Maybe that's not true for everyone, but it seems it's something you can easily test on yourself for a month or two to make your own conclusions.
I noticed that while using caffeine, my energy levels would go down pretty hard after the effects wore off, and my tolerance caused it's effect to diminish.
Since quitting cold-turkey, I've noticed more stable energy levels throughout the day (not a surprising conclusion).
While the net effect on you may not be significant, you have to decide if you want to consume something that does not demonstrate heal benefits.
It could actually be having an effect and I could just not be noticing it because there are many other variables in play.
I suppose my comment was inspired by seeing posts about soda and weight gain and seeing comments of anecdotal evidence for people who have cut out diet soda and notice their weight dropping significantly.
I merely wanted to provide an anecdotal data point (however useless scientifically it may be) to try and give a perspective from the other side of things.
The parent was literally saying that he wanted to convey a different story to the ones commonly heard, in order to give a more balanced picture. Nowhere does that suggest anything about data points, just people sharing stories with different view points.
It's good to have a reminder that "anecdata" != real data every now and then, but in cases where you have a poster clearly acknowledging all that, bringing this up seems like little more than an out of place trope.
people who read these studies and change their habits to drinking less diet soda, hoping they lose weight, are missing the forest and seeing trees. It's a healthy improvement, but not going to impact their life significantly.
That's less than 3 cans. Have a look at what 7/11 sells as a single serving.
That seems like the goal, doesn't it?
If sugar is singled as the cause of obesity, the next step will be taxing sugar and not diet sodas. So expect a thick smokescreen around soda. The fact that overhelming difference between beverages with a huge sugar dosage and without doesn't appear in a study is suspicious enough.
Do you deny that smoking causes lung cancer and premature death? And yet, there are people over 100 years old who have smoked for decades.
Sweet humble brag but considering
> As a side note, my metabolism is actually slower than average and I need to eat on average ~10% calories less than any macronutrient calculator says to stay in the shape (low bf + strong) that I enjoy being in.
You're either a genetic freak or full of it. 90% on all major lifts puts you in the category of amateur competition champion. Go back and run your numbers again, and this time be honest. You're not "strong" at those numbers. You're elite. Which less than 5% of the population fits into. Those kind of people don't browse hacker news. They model for M&F and train for the olympics.
Sample size: 20 people. (Okay what? Are you even trying guys? Releasing something about the the human metabolism with a sample size of 20? Shame on you!) Concluding a weight gain because Ghrelin levels are raised? What? Do you even science? Ghrelin in the first place only tells your brain to look for more food because it signals an empty stomach.
Studies on Nutrition don't get me started...
Is drinking water really that absurd?
the fat study (seven countries) was largely debunked though that doesn't mean all fats in any combination with other macros are good. that sugar is detrimental to your health seems to be a consensus but that doesn't mean other substances can't be bad.
Once you start there, you need to look for evidence to switch to eating pizza and burgers and sodas... which there isn't any convincing evidence, just a constant stream of studies about how bad junk food is. It's much less overwhelming to look at it this way I think.
Its long been understood that soda w/o carbonation isn't palatable because its too sweet and animals stop consuming it. However, when carbonation is present it masks the sweetness which result in increased consumption.
So I think they're probably measuring a secondary effect here.
This controls for the concern you raise above regarding palatability of the beverage, so I don't think that can be a factor there. Critically, there's a statistically significant difference between water and RCB, but not between water and DCB (though the ghrelin level was higher in DCB than water).
From my reading of the paper your concern could certainly be relevant in the rat experiment; I couldn't see any attempt to control for or measure the amount of liquid that the rats consumed, so they could have been drinking less decarbonated beverage.
Soda without soda? :)
As a non-native speaker, this continually fascinates me...
I am skeptical if drinking more Perrier increases your food consumption
Probably time to switch to diet flavor drops + plain water, and exercise more.
How do you get to the point of debating the difference between soda vs. diet soda, as if it's a must-have treat and you are "simply" choosing the lesser of two evils? All soda is UNEQUIVOCALLY bad for one's health! You're drinking a cocktail of chemicals that has no nutritional value, and designed to be addictive. Artificial sweeteners are a gimmick to allow us to recuse ourselves from the innate knowledge of what it is healthy. Selecting a supposedly "healthier alternative" is nothing more than a way to grant ourselves asylum from being personally responsible for our choices. We pretend that our "science" is universally proven evidence backed by chemistry and physics, vs. the truth: it's a manmade lie which no enlightened species would tout as being scientifically valid.
The same mental masturbatuion occurs with vaping. "Vaping is better than smoking!" As if inhaling any mind-altering drug is necessary to "get by", and so it must surely be "better" to attach oneself to the "least worst option", rather than kicking the habit entirely. If vaping is "better" than smoking, what is better than vaping? Oh right, not inhaling anything other than the air we evolved to breathe. Your body wasn't made to inhale chemicals not produced in nature; it was also not made to drink soda. The fact that you don't die instantly from consuming such products does not mean they are not harmful.
The excuses many people make regarding their health is... I'm going to call it what it is: completely and utterly _PATHETIC_. As a species we pretend we are intelligent, but a vast percentage (90-95%?) of the population can't even overcome the most primal appetite for fats, sweets and drugs. Our species will never be capable of rightfully calling itself "enlightened" until we drop all desires for this kind of bullshit. If you're playing mind games with yourself to allow you to "cheat just a little" by consuming unhealthy products, while falsely duping yourself into believing your decisions somehow result in an overall net positive "compared to the (unnecessary) alternatives", you're deluding yourself.
Advice to all alien civilizations: avoid us at all costs. Making contact with us cannot possibly be beneficial to you. We'll either bomb you out of fear and ignorance, or bombard you with our capitalist bullshit in order to pull you into our way of living that will ultimately destroy you from the inside out.
What makes this truly disgusting is that people who choose to destroy their bodies - by drinking diet soda, vaping, or eating junk food - are in fact aware that they are lying to themselves. You know that you are making the wrong choices, but opt for the fallacy that somehow you are not in control. Nobody really believes the marketing companies are pushing out. People are just looking for someone else to give them permission to be unhealthy, desperately listening for someone to tell them what they want to hear. People know they are too weak to have self-control, and are looking for a voice to be their scapegoat.
tldr; Diet soda is not "better" than soda laden with unadulterated sugar. It is simply worse than water, and the fluids you would get from fruits, vegetables, and free-range animals and fish. Allow your brain's thought processes to align with your species' natural evolution. Stop using product manufacturers' claims as a scapegoat. Think for yourself, and don't make excuses.
Edit: To those downvoting: do you downvote because my post is too long and you declined to actually read it, or do you refute the facts? I am normally abrasive in general, but what I've said here really is true. Anyone who reads the whole thing, and still downvotes, is someone with their ...
A general heuristic that is useful in life is that if someone is foaming at the mouth and shouting, the things they say probably aren't that useful. (And you definitely come across like that. EG someone scanning the text would see "_PATHETIC_", and would assume that the emotional part of your brain has been engaged rather than the rational part).
The use very early on of "All soda is UNEQUIVOCALLY bad for one's health!", probably put a lot of people off. It is trivially hard to refute (any example of any soda providing any health benefit (eg rehydration) proves you wrong), and again makes it seem like you are making illogical, emotional arguments.
The use of "Anyone who reads the whole thing, and still downvotes, is someone with their head in the sand" is a cheap nasty trick that will turn people against you even if they agree with you.
Try waiting until you have calmed down and rewriting it in a better way.
My mistake, born from a delusion of my own making, is believing that the entirety of the HN crowd magically falls within the <= 5% of people I consider to be legitimately intelligent, capable of thought relying on science that is universally proven to be true rather than manmade speculation based on tomfoolery. Without seeing any replies countering my statements, I can only assume that these people are petty enough to vote with their trigger-happy index finger rather than taking the time to absorb - and perhaps reply to - the points of discussion I have raised.
Aside, meta: Please do not vote on this comment. By upvoting, you'd be granting my ego a reprieve. By downvoting, you'd be proving my point and also feed my ego. Best bet is to abstain, and let bygones be bygones. This could be -10 or +10 and I'd feel validated. Just don't vote; a 0-1 score says more than anything.
Apparently this misspelling gets by the filter that would otherwise have made this post dead-on-arrival...
To the bigger point, replacing something that is very harmful with something that is less harmful is about the best we can do. Baby steps. Puritanical absolutism is about the worst possible approach if you want to get other people to change their behavior.
Also, nicotine, divorced from all the nasty shit you get from inhaling burning plant matter, is not particularly bad for you. https://www.gwern.net/Nicotine
Those are the type of basic questions you should ask when you read a paper that will lead you to immediately dismiss something like this in under 20 min.
An increase in ghrelin levels was measured, but what about all other other hormone levels that were possibly affected as well? The body is a complex system of thousands of equilibria; if an increase in e.g. testosterone levels (which makes the body burn off fat) was also an effect, this may well offset the effect of increased food consumption -- or even overpower it, causing a weight decline as opposed to a gain.
If a study says that drinking grapefruit juice shortens your lifespan by a year, then I'll cut out grapefruit juice. If it shortens it by a few hours on average, then even if the study is 100% accurate, it's too small to care about.
Especially in news articles, we tolerate this imprecision with health-related findings but not in other areas. You don't see the news reporting that "avalanche kills some skiers". They'll at least tell you "avalanche kills 1 skier and second skier still missing" (unfortunate) or "avalanche kills as many as 350 skiers" (major tragedy).
"A specific carbonated beverage (batch 1234 from supplier X) provided ad lib via a standard rodent water bottle with sipper tube increased weight gain by 10% over the course of 3 months (as they aged 3-6 months) of male sprague dawley rats bred by Harlan USA in 2015, raised two to a cage, fed Z brand rat chow ad lib (10 % fat content), kept on a 12 hr reversed day/night cycle at 18-23 C with relative humidity maintained between 40-60%. Over the course of the study, the rats were removed from the cage only three times a week: for 10 seconds of weighing in the afternoons MWF."
Sincerely, common sense.