So What's the Big Deal About Diet Soda???

[Jean-Paul]

I don't drink regular soda AT ALL. I also advise my clients to cut it from their diet immediately. I mostly drink water (LOTS of water), but at night, especially since I am trying to cut back on beer, I find that I want something with a little flavor, favoring diet Mug Rootbeer and Fresca (basically a diet grapefruit soda). I know that it is not good to drink too much diet soda, but other than a little sodium and some cancer-causing agents like aspertame or nutrisweet, why are most nutritionists so adamantly against diet soda? I maybe drink one or two a night (about the same as I used to drink in beer... Gut begone!).

[Q.]

I've heard that negative stuff about diet sodas, too, for years but I still have a couple a day. My brother railed about NutraSweet because it was approved by the FDA with minimal testing... which doesn't surprise me since the FDA is pretty tightly controlled by the folks they are supposed to regulate.

Although diet Coke is my brand (I also drink water constantly all day, too, however), I've noticed that Diet RC is sweetened with Spenda and "they say" that's healthier.

Speaking of sweetners, I use Stevia in my coffee, hot or iced tea and anything else I sweeten myself. Heard any dirt on Stevia?

Q

[poopy pants]

a little birdie told me vodka and cranberry juice was pretty good

[Jean-Paul]

My evening drink of choice is Vodka with Fresca in a frozen mug. Mmmmm.

[mitsuman47]

JP, you got me HOOKED on those frozen mugs. They're awesome. [img]smile.gif[/img]

[gardener]

Diet coke, 20 oz. in plastic bottles, about 3 per day. Lots of water, an old habit from Texas upbringing. Switch at 5:15 to a gin and tonic, more g than t. Another of those at bedtime.

[Adam Campbell]

Aspartame is just two amino acids, and there's no evidence that its harmful.

But it's been suggested by some researchers that one of the amino acids in aspartame releases methanol when it disintegrates, which the liver turns into formaldehyde, which is apparently, a known carcinogen.

No researcher I've ever talked to has even hinted that aspartame is at all harmful.

Of course, it's possible--but then there are a lot of additives and ingredients in foods that are dangerous. Hell, maybe they should ban high fructose corn syrup FIRST!

I actually drink a lot of Diet Coke because I was always a soda addict and I don't want the HFC or the calories--plus, it seems to clear the cobwebs away when I write. (I've never liked coffee much.)

So I probably drink more than is reasonable, but the only evidence that I know of that it's harmful is a study in which they gave enormous amounts of it to rats, and it caused cancer. But the amounts, apparently, were inhumanly high, when compared on a relative scale. So it became a dead issue.

[bryanc]

There are, however, links to caffeine (which is present in some diet sodas) and bone demineralization. The big deal with soda, I suspect has more to do with what you're NOT drinking because you're drinking soda, than the soda itself. Diet sodas (and most regular sodas in general) are mostly devoid of vitamins and minerals but still take up consumption time and consumption volume. So if one's primary liquid of choice is soda (or coffee, or tea), then one is forgoing more nutritious alternatives like milk and juice and even water (which, while also nutritively devoid, contrubutes to hydration where sodas do not).

[Adam Campbell]

Actually, soda does contribute to hydration. At least according to a study that was done a couple of years ago. They found that almost anything you drink counts toward your daily fluid intake.

It was a pretty well-publicized study. I'm surprised you didn't see it. Here's a link: http://www.ncbi.nlm.nih.gov/entrez/q...&dopt=Abstract


That's not to say that diet sodas are as good as water, just that diet sodas aren't as bad as people think.

[Q.]

Originally posted by Quercus:
Diet RC is sweetened with Spenda

typo... that's, supposed to be SPLENDA

Of course, Mercola thinks that's evil, too! Link He's kind of "out there" on many topics.

Q

[bryanc]

Originally posted by Adam Campbell:
Actually, soda does contribute to hydration. At least according to a study that was done a couple of years ago. They found that almost anything you drink counts toward your daily fluid intake.

It was a pretty well-publicized study. I'm surprised you didn't see it. Here's a link: http://www.ncbi.nlm.nih.gov/entrez/q...&dopt=Abstract


That's not to say that diet sodas are as good as water, just that diet sodas aren't as bad as people think.

Ok, I had a look at the study (hadn't read it before, only heard the news when the study came out in 2000), and here are the major problems I have with it. It was published as a pilot study, and the authors themselves acknowledge that further work needs to be done (i.e. their study is not the definitive answer). As usual, my comments are square paraentheses.

Here's the quick and dirty summary:

18 males, aged 24-39 participated in this study. To be a participant, you had to be of normal and stable weight, exercise for less than 4 one hour sessions per week, not participate in sports on a routine and competitive basis, consume between 20 and 1000 mg/day of caffeine, and have normal gastrointestinal function

[Pretty much your average joe. Note that habitual caffeine users become somewhat tolerant to the diuretic effects of caffeine and thus don't dehydrate as much as occasional caffeine consumers.]

Subjects drank a different combination of drinks every other Wednesday. a) water only, b) equal amounts of water and cola, c) equal amounts of water and diet cola, d) equal amounts of water, cola, diet cola and instant coffee, e) half water, half citrus soda. [NOTE: No combination excluded water completely, so whatever the conclusions of this trial, we can't say that drinking mostly or only diet cola doesn't have an effect on hydration from the evidence in this paper]

Subjects received a total volume of fluid equal to 35mL per kg of body weight, minus 300mL for metabolic water and minus the water contained in the prescribed diet. So, if you were supposed to get 2000mL of fluid (after substracting 300 and subtracting the food water) and you were on treatment D, you would get 500mL each of water, cola, diet cola and instant coffee. Subjects were instructed to drink equal amounts of beverage within a 4-hour time period between 6am and 10pm. For treatment D, all of your coffee was consumed between 6am and 10am, and the other three split evenly throughout the day for the other three 4-hour time periods. [NOTE: So, other than treatment D, subjects drank an equal amount of WATER as they drank each kind of soda every four hours. For treatments B and E, that's a 1:1 ratio of water:soda, for treatments C and D, that's a 1:2 ratio of water:soda].

A subject's bi-weekly schedule went like this:
Week 1: Eat and drink whatever you want
Week 2: Sunday to Monday-eat and drink whatever
Tuesday-Eat a prescribed diet and fluid intake
Wednesday-Eat prescribed diet and drink only the beverages provided by the study
Thursday to the next Week 2: Eat and drink whatever you want

The investigators used change in body weight as their indicator of hydration status. A secondary goal of this study was to evaluate other methods of assessing hydration such as urine collection and blood measures. There is no absolute measure of hydration currently in existence--even the defintion of "dehydration" is not well agreed upon.

Subjects were weighed on Wednesday morning before they received their beverages for the day. Subjects voided prior to weighing and were weighed first thing in the morning before consumption of anything. Subjects were then weighed first thing Thursday morning after voiding similar to Wednesday.

[Here's the biggest possible flaw in this study. The researchers sampled their subjects twice in a 24 hours period at either end of the 24 hours period (0h and 24h). Both weighings happened after a minimum 8 hour fast (sleep) and after voiding. We have NO IDEA of what kind of fluctuations in body weight (hydration) would have occurred during the day, and the hydration effects of whatever it was the subjects drank during the day would have been diluated by the fact that they had consumed _nothing_ for at least 8 hours prior to the Thursday morning weigh-in.]

The 8 hour fast is an important factor in the way you interpret these results. If you're well hydrated before you go to bed, you will urinate X volume of water (as differentiated from urine) in your urine. If you're over hydrated before you go to bed, you will urinate X+Y volume of water the next morning. If you're under hydrated before you go to bed, you will urinate X-Z volume of water the next morning, provided X-Z is higher than the minimum amount of water required to keep the nitrous wastes in your urine in solution. Your body strives to be in hydration-equilibrium at all times. An 8 hour fast gives your body an 8-hour, uninterrupted opportunity to achieve this hydration equilibrium. So when we find that in this study, subjects did not lose a significant amount of weight to indicate dehydration, it's hardly surprising. The authors of this study did not publish the volume of urine voided in the morning prior to the weigh-in (although it was collected).

So, in the end, while this is a great pilot study in that it generates many questions for future study, it doesn't actually prove very much in the way of clarifying whether non-water fluids contribute to hydration. Technically, food provides hydration (up to 700-800mL per day, according to the adjustments in this study), but food isn't considered a contribution to hydration either.

And just interestingly, in the footnote of this paper (though it probably means nothing), "Supported by a grant from The Coca-Cola Company."

[Adam Campbell]

I agree. Of course, it has its limitations. My point was that the conventional way of thinking about hydration is not NECESSARILY correct.

And I'll add that I'd recommend diet soda over fruit juice drinks any day of the week. Despite they're "nutritional" value, they're loaded with HFCS.

This is a fantastic review if you haven't seen it: http://www.ncbi.nlm.nih.gov/entrez/q...&dopt=Abstract

I'd also say that if the researcher is ethical, which is likely (not many get into research for the money, but for more important reasons), the funding has no relevance on its outcome. Whether people like or not, corporations are one of the best sources of funding these days. I say spend as much of their money as you can.

[bryanc]

Originally posted by Adam Campbell:
I'd also say that if the researcher is ethical, which is likely (not many get into research for the money, but for more important reasons), the funding has no relevance on its outcome. Whether people like or not, corporations are one of the best sources of funding these days. I say spend as much of their money as you can.

True enough, but there's a reason why more and more journals are requiring, as a mandatory requirement of publication, the disclosure of funding at the end of a study. Sometimes, it has nothing to do with the ethics of the researcher. But the ethics of corporate funding in university research is pretty far off the topic of this thread. =)