Another reason not to drink sugared beverages

Nicest of the Damned · Post by **Nicest of the Damned** » Wed Mar 02, 2011 5:48 pm

There may be a link between consumption of sugared sodas or fruit drinks and higher blood pressure:

http://www.sciencedaily.com/releases/20 ... ce+News%29

Graham · Post by **Graham** » Mon Mar 14, 2011 2:51 pm

Good article - and did you also notice this :
http://www.sciencedaily.com/releases/20 ... 132543.htm ? Artificially sweetened drinks associated with decline in kidney functiion? They don't say which sweeteners - rather annoying unless we are we to understand all sweeteners are equally damaging. I'm bothered because I use sweeteners in tea and coffee, several times a day.

BrightAngel · Post by **BrightAngel** » Mon Mar 14, 2011 2:58 pm

Not to worry.
Linked doesn't mean "caused by".
They are talking about Association,
and trying to make it Causation.

It's going to take a lot more evidence that that
before I feel the need to eliminate any type of artificial sweetener.

Graham · Post by **Graham** » Mon Mar 14, 2011 3:06 pm

BrightAngel wrote: Not to worry.
Linked doesn't mean "caused by".
They are talking about Association,
and trying to make it Causation.

It's going to take a lot more evidence that that
before I feel the need to eliminate any type of artificial sweetener.

Well, I take your point BA - but they compensated for all the obvious confounding variables and found what they found. I'm thinking that it is probably an effect of one major sweetener, and hoping it isn't the one I'm using.

Kevin · Post by **Kevin** » Mon Mar 14, 2011 3:32 pm

I'm a Type I diabetic, and I've still managed to eliminate all artificial sweeteners from my diet except Stevia, which is plant-derived. No, it doesn't taste just like sugar, and it would probably be awful in black tea.

Aspartame, when consumed regularly, made me feel dopey and mildly depressed.

I never consumed enough Sucralose (Splenda) to make a judgment about it.

There is enough concern about artificial sweeteners (particularly Aspartame) to make me eliminate it from my diet.

Then again, my feeling about food is the closer to its natural form, the better.

But this is just my opinion.

Graham · Post by **Graham** » Mon Mar 14, 2011 4:20 pm

Sometimes I wonder why I use any sweetening at all. After all, if I don't like something without sweetening it, why am I having it? Then again, sometimes it's a comfort thing, sweet tea or coffee, an enjoyable ritual.

If European regulations made it easy, I'd be using Stevia already. It's not in the shops here, available by mail-order only, but I guess I'll have to make the effort and try the liquid extract. I did try powdered stevia leaves many years ago and didn't like t at all.

wosnes · Post by **wosnes** » Mon Mar 14, 2011 4:30 pm

Graham wrote:Sometimes I wonder why I use any sweetening at all. After all, if I don't like something without sweetening it, why am I having it? Then again, sometimes it's a comfort thing, sweet tea or coffee, an enjoyable ritual.

I think that's like saying if I don't enjoy pasta without Parmesan, why am I eating pasta? (Might be a bad example, but best I came up with quickly.) But seriously, I think we're getting to the point of over thinking our food and beverage choices.

Sienna · Post by **Sienna** » Mon Mar 14, 2011 7:09 pm

Although it may seem like they controlled and compensated for everything, BA is right: correctional or association is not the same as causation.

Because I think examining scientific studies is interesting, I'm going to spend a little time talking about that, but since that may be long and boring for many of you, I want to say this first. There are constantly studies coming out that say certain things are good or bad for you. But compiled they mostly look like: Substance A is good for Organ B, but bad for Organ C, but in moderation is probably more good than bad, and moderate is less than quantity D unless you are a woman in which case it is less than quantity E. Oh and by the way, if you eat/use Substance F none of the above applies.

So I look at it like this: if it were possible to eliminate all cancer and disease (leaving only accidents/violence as potential cause of death) by eating MagicJuice and ONLY MagicJuice, for the rest of your life, BUT MagicJuice tasted like the most appalling thing in the world to you and skipping even one dose of MagicJuice or eating one thing besides MagicJuice would void its protection, would you do it? I personally wouldn't. Yes, I want to live a long happy life. But an overly restrictive diet would not qualify as happy for me. So I read the literature because its interesting, but if a change would make me feel deprived I don't bother. Because even MagicJuice won't protect you from getting hit by a bus.

And now, long potentially boring scientific stuff.
============================================

I pulled the abstract for the actual scientific article in question (http://cjasn.asnjournals.org/content/6/1/160.short). Unfortunately it was published in a rather obscure journal, so I don't have access to the full article (I have access to 4 different university libraries and so this is a rarity for me!)

However, even from the abstract I see one big problem with your conclusion that artificial sweetner causes kidney function: the study doesn't examine the use of artificial sweetner, it looks specifically at artificially sweetened soda. In fact, this is the articles conclusion from the abstract:

Consumption of â‰¥2 servings per day of artificially sweetened soda is associated with a 2-fold increased odds for kidney function decline in women.

While the abstract suggests that sugar soda did not have an effect on their measured outcomes, without actually reading through the actual article it is difficult to fully evaluate. Further complicating this particular issue is this study: http://www.nature.com/ki/journal/v77/n7 ... 9500a.html It looks at the effect of sugar-sweetened soda on kidney disease. What does it find? Well, unfortunately its not as simple as sugared soda does or doesn't lead to an increased risk of kidney disease.

From the paper:

Our findings are consistent with previously published reports in which high sugar-sweetened soda consumption was associated with prevalent hyperuricemia and renal injury

So it causes kidney disease, right?

Also from the paper:

Yet this study, to the best of our knowledge, is the first to examine whether sugar-sweetened soda consumption is associated with incident forms of these diseases. The results of these incidence analyses add an important note of caution to the literature on sugar-sweetened soda and HFCS. Although the cross-sectional analyses performed in this and other studies4, 19 support a hypothesis that increased HFCS-sweetened soda consumption leads to higher uric acid levels that in turn induce renal damage, the longitudinal analyses do not support this theory.

So actually depending on how you analyze the data, you get two different answers. This particular paper cites a dozen or so other studies participating in the "is sugared soda bad for kidneys" debate and concludes with this very telling remark:

Therefore, our findings add to but in no way close the heated discussion over the potential dangers of sugar-sweetened soda.

And to me a version of the above quote could be added to the end of just about any scientific article dealing with nutrition. Because data is data - but so much goes into experimental design, execution, analysis and interpretation, that two excellent researchers can get sound but different results from well-executed experiments. No one actually has to make a mistake to get a result that doesn't well represent the Absolute Truth. And since we can't really know what the Absolute Truth is, we end up with heated debate and a constantly changing knowledge base.

[/quote]

Graham · Post by **Graham** » Tue Mar 15, 2011 8:32 am

@ Wosnes - I get your drift, and if I had a waistline of 50% of my height or less, I'd probably be more relaxed about this sort of issue - but I'm overwaist and struggling with it. It feels like every strategy I adopt short of renouncing sugar altogether turns out to have it's own punishing qualities, it's an issue I wrestle with.

@Sienna - not boring in the least! If I accept what you are saying, I'll have to say that Science Daily rather lets down its readers by not mentioning the contentious background in which these researchers findings need to be placed. My reasoning, extending from the report I mentioned, was a bit "quick and dirty" but not irrational - now you add extra texture and complexity to my reflections on the subject. I did notice the study was about soda, by the way - it's just that, when they say sugared soda is ok, and artificially sweetened soda isn't, what else but the sweeteners should I attribute the negative association to?

And finally, I have a request for you, since you're au fait with the territory: could you translate this sentence for me: "Thus our study shows that high consumption of sugar-sweetened soda was associated with prevalent but not incident hyperuricemia and chronic kidney disease." ?
(it's particularly that distinction between prevalent and incident, I don't get it.)

wosnes · Post by **wosnes** » Tue Mar 15, 2011 1:45 pm

Graham wrote:@ Wosnes - I get your drift, and if I had a waistline of 50% of my height or less, I'd probably be more relaxed about this sort of issue - but I'm overwaist and struggling with it. It feels like every strategy I adopt short of renouncing sugar altogether turns out to have it's own punishing qualities, it's an issue I wrestle with.

Graham, from what I recall of your previous posts, you eat well and get quite a bit of exercise. What if you didn't know about height/waist ratios, BMI and so on and so forth? What if you just were more relaxed about this sort of thing? Correlation isn't causation.

I'm sure that most people who are "overwaisted" aren't eating as well as you do -- so the correlation is probably accurate. But in someone who eats well, it's probably meaningless.

EDIT: Recently I've noticed that the commercials for medications to lower cholesterol say "elevated cholesterol might increase risk for heart attack and stroke." MIGHT. Yet we all act as if elevated cholesterol means that we will have a heart attack or stroke and die. Some people undoubtedly will. So will some people with completely normal cholesterol levels (In fact, my cholesterol when I had my heart attack was well within normal ranges. Actually all my labs were great -- and I still had a heart attack and almost died from it).

Sienna · Post by **Sienna** » Tue Mar 15, 2011 2:03 pm

Hi Graham,

Incident in this context basically means new cases of kidney disease. The relationship between prevalence and incidence is often stated as:

prevalence = incidence x duration

So if disease A struck everyone in the world, but only for 1 day and disease B only struck 10% of the world but lasted for years, then disease A would have a higher incidence (more people develop a new case), but a lower prevalence. What this means from a research perspective is that for studies where you are trying to link a cause to a disease, you must attempt to distinguish between prevalent cases and incident cases - which is not always trivial.

So basically the article is suggesting that while people who drank soda overall had more kidney disease ("associated with prevalent...hyperuricemia and chronic kidney disease"), but that there was no direct evidence that drinking soda *caused* the kidney disease ("but not incident hyperuricemia and chronic kidney disease")

But how could that be? One possible explanation (and I am definitely NOT claiming it is the correct one - I honestly have no idea!) for this is that soda increases duration of kidney disease or makes already present kidney disease worse. As you can see from the relationship above, by increasing the duration of the disease, the prevalence will increase - even if the incidence does not change. If that were the case (again no clue if it actually is), it would mean that if you had kidney disease you should avoid soda, but if your kidneys were fine you could indulge in soda without worrying.

As for Science Daily letting down its reader, it's my opinion that most (if not all) lay publications presenting scientific finding overstate and over-glamorize findings. I actually did a paper on the topic with regards to obesity and obesity treatment back in college. It's amazing how a scientific conclusion of "if we knock out this gene in mice, they no longer get fat" translates to "scientists discover magic bullet for obesity treatment!" in the headlines. That doesn't mean that the lay publications are wrong, or even entirely bad - they just have a different purpose: to sell copies. I've learned its always worth at least pulling an abstract (and paper if possible) to get a better idea of what the scientists themselves are claiming.

Graham · Post by **Graham** » Tue Mar 15, 2011 4:22 pm

wosnes wrote:
Graham wrote:@ Wosnes - I get your drift, and if I had a waistline of 50% of my height or less, I'd probably be more relaxed about this sort of issue - but I'm overwaist and struggling with it. It feels like every strategy I adopt short of renouncing sugar altogether turns out to have it's own punishing qualities, it's an issue I wrestle with.
Graham, from what I recall of your previous posts, you eat well and get quite a bit of exercise. What if you didn't know about height/waist ratios, BMI and so on and so forth? What if you just were more relaxed about this sort of thing? Correlation isn't causation.

Wosnes, what a fine question! I meant to say a little more in my original response to your comment about "overthinking", but got distracted. Like you I also had a heart attack, and like you, it was unexpected, and a great surprise to me and my doctor. "You are the last person I would have expected to have a heart attack" he said, when I saw him after getting out of hospital.

wosnes wrote:I'm sure that most people who are "overwaisted" aren't eating as well as you do -- so the correlation is probably accurate. But in someone who eats well, it's probably meaningless.

EDIT: Recently I've noticed that the commercials for medications to lower cholesterol say "elevated cholesterol might increase risk for heart attack and stroke." MIGHT. Yet we all act as if elevated cholesterol means that we will have a heart attack or stroke and die. Some people undoubtedly will. So will some people with completely normal cholesterol levels (In fact, my cholesterol when I had my heart attack was well within normal ranges. Actually all my labs were great -- and I still had a heart attack and almost died from it).

In my case my cholesterol was slightly elevated, I was smoking, and I was on an antidepressant which I later read was suspected of causing heart-attacks in some people. I had the angioplasty and stent and all the usual drugs - though oddly no offer of any sort of psychological support. I was scared. I felt ill and within a year was told my arteries were narrowing again and was offered further treatment. Somewhere around there I got into "natural" remedies - I stopped all the drugs, used food supplements instead and got serious about trying to reduce my waistline - If my GP had measured that he would have found I had been in a "high-risk" category for quite a while.

So when it looks like I'm overthinking things - you're looking at someone who had a big scare and really, really doesn't want to go through all that again. My waistline was the biggest clue to my precarious status and hence my current focus on it. When my weight starts to go up to >11 stone (154lbs upwards) I start to get angina when I'm cycling. I still feel a bit too close to it all happening again, and sometimes I may react too quickly or emphatically because of it.

Graham · Post by **Graham** » Tue Mar 15, 2011 4:32 pm

@Sienna - thanks for the clarification - I don't suppose you'd know of a book or on-line source I could consult to get clearer about all this? I sort of get what you are saying, but I'm spinning off into new questions and not knowing where to go for answers.

Sienna · Post by **Sienna** » Tue Mar 15, 2011 4:54 pm

Hi Graham,

If you are looking for details on how to organize and/or analyze epidemiological studies, try The Encyclopedia of Epidemiologic Methods. It's online at google books here: http://books.google.com/books?id=8qIMMb ... &q&f=false

It's long, but makes for a decent reference (you can also use the google books search function to search within it).

In terms of honing skills at reading and evaluating scientific papers, I've seen Trisha Greenhalgh's How to Read a Paper: The Basics of Evidence-Based Medicine highly recommended - although I haven't read it myself. I just looked it up and it appears that at least part of it is available on google books: http://books.google.com/books?hl=en&lr= ... &q&f=false

I sort of get what you are saying, but I'm spinning off into new questions and not knowing where to go for answers.

And for what it's worth, the above is actually a good thing, and should make you go

instead of

. A good paper will cause a good reader to ask more questions than they get answered. It's part of perpetuating scientific inquiry. And I know it may not seem like it makes sense on the surface, but the more questions I have about a topic, generally the better I actually understand it. It's when I think I completely "get it" that I usually turn out to be totally clueless - probably because no one really completely 100% gets it all.