A Study Found Diet Coke Is Better for You Than Water (Sort Of)

I’m sure you’ve seen the studies published from time to time showing that diet soda is arguably pretty bad for you. (Their evidence is never very strong.) But have you seen the new study who discovered that diet sodas were better than water for people with type 2 diabetes? Not only is this a real study, it’s well designed and we should pay attention to it, according to an epidemiologist I spoke with who was not involved in the study.

That epidemiologist is Gideon Meyerowitz-Katz of the University of Wollongong, who has written about it. here. When I asked him whether it was a good or bad thing that this study had largely escaped media attention, he replied, “It’s much more robust than most scientific data that gets media coverage.” The study was not sponsored by any commercial beverage company.

What the study revealed

In the SODAS (Study Of Drinks with Artificial Sweeteners) trial, researchers from the University of California, Irvine and the University of Minnesota, Minneapolis recruited adults with type 2 diabetes who were accustomed to drinking artificially sweetened beverages (including, but not limited to, my one true love, Diet Coke). The study was funded by the National Institute of Diabetes and Digestive and Kidney Diseases of the U.S. National Institutes of Health.

Half of them were asked to switch to drinking water, and each received three servings per day of their diet drink of choice or water of their choice (unsweetened seltzer water included). The study lasted 24 weeks. There were 181 people enrolled, of whom 179 completed the study, which is considered a fairly large group for a study of this type. (This is twice as large as an older study that I’ll compare it with below.)

The main result studied by the researchers was hemoglobin A1C (HbA_1C) as measured by a blood test. This is a commonly used test to monitor blood sugar control in people who have diabetes or are at risk for it. The higher your HbA1C level, the higher your blood sugar levels have likely been over the past three months or so.

The results: HbA1C improved slightly in the group that drank artificial sweeteners: from 7.19% to 7.14%. He had worse in the group that drank water, from 7.20% to 7.44%.

The researchers collected a few other measurements, for good measure. Fasting blood glucose, fasting insulin, and “time in range” measured by a continuous glucose monitor all favored the diet drink group. People in the diet drink group lost a little weight (an average of two pounds), while those in the water group had a stable weight. The researchers called this difference in weight loss “statistically significant, but not clinically significant.” In other words, probably real, but too small to matter.

Bottom line: There was no real benefit to people in the study by switching from diet soda to water; on the contrary, it could have slightly harmed their health.

What this means for you and your Diet Coke habit

OK, maybe I mean Me And My Diet Coke habit. I fully admit that I have a bias here, but in an informed way. I like my Diet Coke. I’ve also closely followed the research on artificial sweeteners over the years, and while I wouldn’t necessarily defend my soda as a health food, nothing has ever convinced me that it is. bad In my opinion. (Sugary sodas are another story; we should probably all avoid them.)

We now have a fairly large, well-designed, independently funded study showing that artificially sweetened drinks may be better for you than water. I still haven’t seen any media coverage on this, although a study with opposite results I had a blanket a few years ago. This study looked at 81 diabetic women in a weight loss trial, and their HbA1C levels improved slightly with water compared to diet drinks. Despite everything, an expert who Everyday Health talked about it said he “believes that the health risks of diet soda are overstated.” (Meanwhile, the authors of the more recent study point out that comparing that study to theirs isn’t quite comparable, since that was a weight loss trial and this one is not.)

This is an important point to remember any study on a specific food: these generally apply to a specific medical condition or population. We like to categorize them in our minds as “Diet Coke good” or “Diet Coke bad,” but each study only gives us one piece of the puzzle, not a generalization. For example, this study tells us nothing about the effects of Diet Coke on people whose diabetes is poorly controlled, or who don’t have diabetes at all; and it says nothing about measurements other than those related to blood sugar. That’s not even the case specifically study Diet Coke, although it is likely that Diet Coke was one of the more popular drinks chosen by participants.

To be clear, it’s entirely possible that this isn’t a real effect and that water and diet drinks are basically equivalent when it comes to your blood sugar and health. Meyerowitz-Katz says it is probably This is the most likely explanation, but we can’t rule out the possibility that diet sodas may help control blood sugar in type 2 diabetes. Perhaps they satisfy sweet tooths and help people avoid other sugary snacks, for example.

The researchers write that their main takeaway is that “maintaining habits [artificially-sweetened beverage] dietary intake may be a tool to continue to help manage T2D if blood glucose measurements are controlled and stable. Meyerowitz-Katz agrees: “In the worst case scenario, there is no difference between diet soda and water when it comes to controlling diabetes. At best, diet drinks might be slightly better.