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mmastrac

Hrm, no carbonated water in the study [1]?

> 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...

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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.

FYI, the paper says:

> 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.

But there doesn't seem to be carbonated water?

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!)

I think they tested on humans separately, at least according to my understanding of the paper (linked elsewhere on ipfs in this thread).

Screenshot (CW = carbonated water):

https://pbs.twimg.com/media/C_-Rcr_UwAASYae.jpg

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.

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).

>The paper is $35

It's on sci hub.

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".

Searching by DOI will give you results. for this paper it is:

     10.1016/j.orcp.2017.02.001

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)."

That second reference doesn't cite anything concrete.

[1] and [2], both citing the original paper as a source, show that Carbonated water was part of their experiments.

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

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