The John Hopkins Bloomberg School of Public Health released a study this month which concluded that “liquid calorie intake had a stronger impact on weight than solid calorie intake.” I believe this study can be found in American Journal of Clinical Nutrition. Effectively, this study points an accusing finger at soft drinks and related beverages when it comes to our national obesity problem.
The researchers speculated, as a result of this study, that the body has more trouble regulating liquid calorie intake than solid calorie intake. Though the study didn't go as far as to speculate why, I figure this may be because adult humans have traditionally found the vast majority of our caloric needs in solid food, so we just don’t have the biological mechanisms in place to properly nourish ourselves with liquids.
In addition to that study, another paper released by John Hopkins in March in Biochemical and Biophysical Research Communications concluded with results that led researchers to hypothesize that while glucose tends to curb appetite (glucose is an important carbohydrate, and it makes sense that it would make us full), fructose, also an important carbohydrate, but which is often used in large quantities as a sweetener, may actually increase appetite. This study was not specific to soft drinks, but the lead author did identify soft drinks as the most notable source of high fructose sweeteners.
Coupled together, I’d say these two studies offer still more convincing evidence against daily consumption of soft drinks and sweetened beverages. I won’t say I never consume soda (I do love me some root beer), but when I do, I’m well aware it’s not just a thirst quencher. As a can of soda has140-ish calories, mostly from refined sugars, I tend to imagine an ounce and a half of table sugar in a ziplock bag and consider it a hefty dessert.