Diet Drinks Help Weight Loss


No diet sodas

The meme that drinking diet sodas causes weight gain has been ricocheting around the Internet for years. Generally, this claim has been based on observational studies in which researchers find that fat people tend to drink more diet drinks than do skinny people. This has always seemed to me to be a case of post hoc ergo propter hoc, i.e., after this, therefore because of this.

I know that I will annoy some epidemiologists, but a large proportion of observational studies seem only slilghtly more respectable than casting horoscopes. Why? Because, even with the best will in the world, it's nearly impossible to eliminate confounders so that a real causal relationship might be revealed.

A new randomized trial study in the journal Obesity (and funded by beverage companies) followed more than 300 people through a weight loss program. The only difference is that half were asked to drink at least 24 ounces of water per day and other half to drink 24 ounces of non-nutritive sweetened (NNS) beverages per day.

The program involves 12 weeks of losing weight followed by 9 months of weight maintenance. The study found that those consuming diet drinks lost an average of 14.2 pounds whereas those drinking water dropped an average of 10 pounds. The researchers chose 12 weeks as the length of the study because prior work shows that weight loss slows considerably after six months in a treatment program. (I know from personal experience that that is so.)

The study further notes:

Based on the design of this study we are unable to say, what is the mechanism for the greater weight loss in the NNS group compared to the water group. Weekly hunger scores were significantly lower among the NNS group than the water group although the absolute changes were small. While it is plausible that the NNS participants were more likely to adhere to the dietary recommendations due to less hunger than the Water group we cannot conclude this based on this study. Some authors have suggested that use of NNS may increase appetite for sweet foods and disrupt regulation of energy balance. Weight loss results for the present study suggest that NNS consumption did not increase energy intake from other foods compared to water. This is consistent with other studies that have not found increased consumption of sweet or high energy foods while using NNS. Further studies will be needed to ascertain the mechanism(s) that may be responsible for the weight loss results.

Look, it may turn out that the observational studies suggesting that drinking diet sodas make people fat are true, but I wouldn't bet on it. It has always seemed much more plausible that obese people drink diet soda because they don't want to get even fatter by consuming the extra calories in sugar-sweetened drinks. Sometimes interestingly counterintuitive claims are bunk. So diet soda drinkers unite! You've nothing to lose but your excess avoirdupois!

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  1. Yeah, it’s not the two triple-patty bacon cheesburgers causing the weight gain, it’s the diet soda.

    1. If you leave off the bun and skip the fries, that’s a true statement.

      Of course, I never skip the fries.

    2. It’s not the beef, pork or cheese in that burger, it’s more the bun, the fries and the sugary drink.

    3. At lunch today, I got a salad and a Diet Mt. Dew, so I could justify getting one of their deliciously fatty oatmeal chocolate-chip cookies.

      That’s calorie shifting, to me.

  2. Best to drop coke from your diet altogether though.

    1. If I could do more coke, I think I’d lose weight faster.

      Wait…we’re talking past each other here….

      *sniffs and looks around nervously*

  3. Diet Drinks Help Weight Loss

    And water is wet. Very wet.

    1. Straight-out substitute diet for sugary drinks, and this strikes me as intuitively, perhaps even trivially, true.

      Observational research can’t test a mechanism by which diet drinks could short-circuit or do an end-around of normal metabolic processes that might make an exception to the normal pathway: sugar triggers insulin triggers fat storage.

  4. Working at the old BK as a yute in the late 70’s, our joke about the lardass order went as follows:

    “Gimme a Whopper? with Cheese….better make that a double. And a large fry. And a large onion ring. Oh, and a Tab?. BETTER MAKE IT A LARGE…”

    We called Tab? (later Diet Pepsi when we changed providers) “The Neutralizer”, cause whatever else fat people ordered, they ALWAYS ordered Tab….cause it neutralized all the fat calories. So – if you ordered MOAR bad food, “…better make that Tab? a large…” cause – moar neutralizer needed.

    So – I’d say, “Sure, I believe fat people drink diet drinks more than the population at lard..er, at large, cause it’s ritualistic behavior that helps them pretend they’re ‘doing something’ about their weight, when in fact all the other shit they’re eating is what’s keeping them fat.”

    Any port in a storm. Whatever helps you sleep at night. People deceive themselves like this all the time – it seems like hardwired behavior to me.

    What were we talking about?

    1. PS Almanian is considering a change to teh Diet Dew? – finally – precisely because all the calories from the regular Dew do not shed so easily now that I’m in my 50’s.

      Pretty convinced that a switch to Diet will drop enough cals that – when combined with my exercise and a bit-more-sensible diet, I’ll lose weight fer sure.

      Cause – zero calories 5-6 times a day versus….a zillion. Prolly gonna lose some weight.

      We’ll see…if I can do it. Been drinking the High Octane stuff for about 40 years, so…this won’t be easy.

      1. Like you, I’m also past the 5-0 mark. I shifted over from regular to diet Dew. I don’t drink it that often, so it’s tolerable.

        Mostly, it’s sugar-free Red Bull these days.

      2. Cause – zero calories 5-6 times a day versus….a zillion. Prolly gonna lose some weight.

        Maybe. People who think calorie reduction and exercise will make them “lose weight fer sure” don’t usually have much experience trying to lose significant amounts of weight.

        1. Care to share your secret then?

          1. east less; move more; till the end of time.

            1. fookin’ typo 😉

          2. Fat accumulation is driven by insulin. Smooth out/reduce your daily insulin by limiting sugars and carbs (which will likely also reduce your total caloric intake), and you will see results. Regardless of exercise.

            1. Calorie intake seems irrelevant for me. I can’t tell you how many people have told me I’m wrong, but 1200 Calories had me losing a pound a month, but ad libitum had me losing three pounds a week.
              It works for upwards of 75% of obese people, anyway. I don’t know why the others don’t respond as well. Maybe they have other problems?

          3. Care to share your secret then?

            Like R C Dean said above, “sugar triggers insulin triggers fat storage.”

            I used to weigh 400 lbs. I did the low-cal, low-fat struggle down to 365 lbs over 3 years. (Yeah, a big thirty-five pounds in thirty-six months.) Then I tried low-carb, high fat. No alcohol, as little sugar as I can manage, very little bread or other starches. I eat a lot of meat and high-fiber vegetables, some high-fat dairy. Eat as much as you want, just eat what you’re supposed to. I dropped 125 lbs in 8 months and kept it off for 10 years now. My blood work is much better too.
            Even though it came out long after I lost weight, Gary Taubes’ book Why We Get Fat describes and explains my experience perfectly.

            1. Congratulations on losing the weight.

      3. Some of us are Viking berserkers who inherited the only weakness of the Nordic Gods: phenylketoneuria.

        Ergo, no nutrasweet allowed. I choose water, coffee, whisky, and beer instead of anything diet. But it does suck having only two options to drink during the workday.

        1. Whiskey and beer? Save those other vices for the weekend.

        2. So when do you drink water and beer?

        3. So you’re like the anti-SugarFree?

  5. post hoc ergo propter hoc, i.e., after this, therefore because of this.

    Listen, Bailey, we love you, but it’s time for an intervention. If you’re going to give the translation for a (fairly common) Latin phrase, you don’t bridge the two phrases with a abbreviated form of a Latin phrase (id est) that even less people know much less consistently confuse its usage with exempli gratia.

    1. Huh – a lot of people do confuse i.e. and e.g., but I’m not gonna criticize Ron when he uses it correctly!

      PS And I think you meant “fewer” people….

      /pedant the pedant

      1. You’re right. Using “less” so closely together must have thrown me off.

      2. It really isn’t that difficult to use correct spelling and grammar. Be professional and disciplined in everything that you do for the cause.


  6. The only difference is that half were asked to drink at least 24 ounces of water per day and other half to drink 24 ounces of non-nutritive sweetened (NNS) beverages per day.

    With all due respect, that “difference” is bullshit.

    1. Yet it produced a difference in outcome.

  7. Umm, the argument is that artificial sweeteners interact with gut sweet receptors and create an insulin spike that lowers blood sugar and makes people extra snacky. The “fat people drink diet soda” bit is just the folk interpretation of it.

    The actual clinical studies on this have been narrow, but so far show that it does trigger a hormone that mediates glucagon and insulin responses, but more research is needed (natch) to tell when (if at all) that translates to an insulin spike.

    1. That’s my interpretation too. They’re certainly far better than regular pop, but they may have their own problems.

    2. The fat accumulation from insulin spikes isn’t so much from snacking during the crash (although that doesn’t help). Its mostly because insulin sweeps sugar out of your system by converting it to fat.

      1. ^This, but the snackiness keeps this going by creating a new blood sugar spike, releasing further insulin, sweeping more calories out of the blood stream and onto one’s midsection.

      2. But how does sugar-to-fat make any difference if the same total energy is being used by the body?

  8. HM: id est = that is, no?

    1. Yes.

      I’m just teasing.

  9. (and funded by beverage companies)

    Hmm, ok.

    Regardless, diet soda still tastes fucking awful.

    1. I’ll never forget my first Diet Coke. I honestly thought the stuff had gone rancid or something, before being assured that was the way it was supposed to taste.

      1. Coke Zero almost tastes ok, but overall still a thumbs down.

        I generally only drink coffee and water anyway…well, beer too.

        1. Mix it with shitty rum. It’s not so bad.

        2. Coke Zero + Sailor Jerry = me not having a pleasant next day

          The vanilla or cherry ones work best.

          1. Mmmmmm, Cherry Coke Zero. My wife swears it goes great with North Shore Distillery #6 gin.

      2. I’ll never forget my first Diet Coke.

        Many years ago, I was eating at a sub shop with my wife and, without looking, accidentally drank some of her Diet Coke. It was awful. Now, after a decade not drinking sodas, all colas taste that way to me. It’s very disappointing. I used to love Coca Cola.

        1. I’ve had almost no regular pop in probably close to 15 years. On the rare occasions that I have it, it tastes terrible to me now.

          1. pepsi/dew throwback on weekends only.

        2. When I do drink one now, the taste is still good I would say, but I definitely feel bloated…which I don’t understand how the daily soda drinker enjoys that feeling.

          1. Do you get that terrible light-headed feeling? It’s awful.

            1. Oh yeah, I guess I find the bloating to be more noticeable and usually what keeps me from reaching for a soda (work stocks the fridge with free sodas).

              Oh yeah, question for you. I have recently discovered how embarrassing I am at pull-ups. Should I care at all, and if so, what can I do to get better?

    2. It grows on you. Like a rash. Seriously though, the wifey only drinks diet which means sarc only drinks diet. Got used to it.

      1. “That is a delicious burger! My girlfriend is a vegetarian, so that pretty much makes me a vegetarian.”

        1. I went out with a vegetarian. It barely lasted one date. She introduced me to a Brazilian orange that had the toughest pulp I ever chewed, but the flavor was awesome.

    3. Diet Cola is gross, there are some decent diet fruit flavored soda’s

    4. Some of the citrus (Fresca, tangerine Diet Rite) or chocolate (Canfield’s & imitators) flavored ones are OK. Otherwise I make no-cal drinks fresh from powders.

  10. Generally, this claim has been based on observational studies in which researchers find that fat people tend to drink more diet drinks than do skinny people. This has always seemed to me to be a case of post hoc ergo propter hoc, i.e., after this, therefore because of this.

    My oldest sister has been fat since college. About a year ago she switched from Coke to Diet Coke, and lost 15 pounds over the course of the year. She didn’t make any other changes to her diet or exercise. This type of study would count her as an example of a fat person drinking more diet soda than average, since she’s still too heavy after the 15 pounds she lost.

  11. CPA: Wrong. Diet coke is Olympian nectar.

    1. I suppose you like cilantro, too, Ron.

        1. I suppose you like eating bedbugs, too, HM.


          1. Frickin bedbugs!
            Had an epic battle with them a couple years back after my kid came home from a NYC trip. The hardware store’s poison sprays, powders and bombs helped… sort of. Diatomaceous earth seemed to discourage them from spreading beyond that room. Finally, I cooked them out with two Big Buddy heaters. Cracked the window open an inch to let in oxygen for the heaters, took the room up to 150?F and kept it there for 6 hours. Did the same to the spare room the kid moved into too. No more bedbugs. Repeated the procedure a week later, just to be sure.

            1. I hope you moved your kid out of the room first.

      1. Cilantro has its uses. Guacamole is not one of them, but the greatest Mexican restaurant in history used it in their salsa, so it can’t be all bad.

        1. Salsa without cilantro is like… not even salsa.

          1. My brother and I think that serving it warm was a bigger deal than the cilantro.

          2. Who needs salsa with their cilantro?

            All you need is chicken al pastor over a corn tortilla with cilantro and onion, generously doused with habanero hot sauce.

            It is perfection.

            1. Little mexican shop across the street always has some sliced up skirt steak marinading in al pastor. Ill carmalized sone onion and poblano. Stir fry tge al pastor and eat it in a corn tortilla with some cilantro and a touch of creama. Bomb. I do put a little but of cilantro in my homemade guac.

          3. The Libertarian Wife is one of those genetic mutants to whom cilantro, the yummiest of herbs, tastes like soap. This made for many problems when we lived in Austin, the font of Central Texas Tex-Mex.

      2. R: Yes. Absolutely. My wife loathes it.

  12. Well, the study doesn’t prove much of anything in regards to non-calorie sweeteners and weight loss, because the water “control” group was allowed to consume NNS sweeteners in any thing they liked provided they didn’t add it themselves or consume it in diet soda form. So essentially they aren’t really comparing anything.

  13. I can’t stand Diet Coke or any of those others called “diet”. Now I’ll drink Coke Zero (and the other Zeros) as much as I can. But if I’m in a restaurant and they don’t have Coke Zero, I get a regular coke. I absolutely hate the taste of Diet Coke.

    At home, I mostly drink sweet tea (1/2 cup of stevia/sugar blend per gallon). It’s about 50 calories (I guess) per glass. Not too bad, but not great. If I could find a NNS I could enjoy, I would switch to that.

    Am I fat? Yes. But I’ve lost and maintained weight since switching. I’m also still losing more weight, but that comes from other dietary adjustments and more exercise. Still have a long way to go.

  14. The difference between having sugary drinks in my diet and nonsugary drinks is 10-15 lb for me. It never made any sense whatsoever that having a half a cup of sugar was better than not having it. Now if they could only make diet vodka.

    1. calorie free alcohol? Sign me up!

      1. I can guarantee you, you will gain 0 lbs from drinking straight Vodka. Or any hard liquor for that matter. The alcohol calories in your two fingers of gin are not processed by your body the same way sugar calories are.

        Beer on the other hand, or sugary mixed drinks, or maybe even flavored vodka have calories from other sources.

        Try a mixed drink, with a diet soda of your choice for a nearly calorie free inebriation.

  15. The awful tasting ones are the ones that use SweetnLow, aka Saccharin, That stuff has a rather distinct taste and after taste.

    Splenda, aka Sucralose, on the other hand is awesome. And soda sweetened with it tastes a lot better. For me it tastes very close to sugar. Splenda has replaced sugar almost completely in my household.

    Both SweetnLow and Splenda use Dextrose, and if you find both of those sweeteners taste bad to you, Dextrose maybe to blame. Try Stevia in that case.

    But honestly, in this day and age, if you are not replacing at least some of your sugar with low-cal substitutes you are doing your physical appearance a major disservice.

    1. IIRC, sucralose is just a sugar molecule with an OH group stripped off and replaced with a chlorine atom. It still sets off the sugar receptors on your tongue the same as sugar, but the chlorine atom prevents it from properly fitting into the enzyme that breaks down sugar, so it passes through the body undigested.

    2. I actually like swet n low in mu tea. My wife doesn’t like splenda but I have no problem with it. I’ll do a splenda brown sugar blend in my oatmeal.

  16. Im thinking the carbonation creates gas which makes people feel bloated therefore less hungry.

  17. Generally, this claim has been based on observational studies in which researchers find that fat people tend to drink more diet drinks than do skinny people.

    By this reasoning, cold medicine makes you sick. Every time I see someone taking cold medicine, they’re feeling under the weather. I rarely, if ever, see someone taking cold medicine when they’re perfectly healthy.

    1. I’ll add that, even if the alternative is water, the argument still holds. People content with just water are likely people for whom taste sensations are not as important a stimulus.

  18. I’m planning to start vaping to lose weight?either flavorings alone or with nicotine.

  19. After a serious accident in December (a large round hay bale fell on him), my Dad switched to diet soda and lost 62#.

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