Drinking for Weight Loss: Results Will Vary

It seems like a simple proposition. Stop drinking your calories. Drink water or other non-caloric beverages instead. In the calories-in-calories-out way of thinking, weight loss will be automatic. Drink only water and you’ll be drinking for weight loss.

The CHOICE  Study

This study actually tested the drinking for weight loss proposition. It was a rigorous randomized and controlled study. Three arms, six months. The control group got attention and encouragement just like two treatment groups. For example, they had monthly weigh-ins and group sessions. They had weekly monitoring. They got general advice about weight loss. But the control group didn’t get instructions to change their drinking habits. The two treatment groups did.

Researchers told one treatment group to replace two or more servings per day of caloric drinks with water. For the other group, the advice was to swap the caloric beverages for diet beverages.

It turned out that the diet beverage swap worked better. Their odds of losing five percent of their body weight more than doubled. In the water group, the odds were not significantly better. Close, but they didn’t ring the bell.

Results Vary

Why was this not a slam dunk? A new honors thesis published by the the Nutrition Research Institute at UNC-Chapel Hill examines this question. Working with Deborah Tate, Sahil Vasa analyzed the variables that predicted responses to the drinking swaps.

One important fact is that different people are quite different in their drinking habits. Most people got less than 40 percent of their beverage calories from soda. But 29% of the participants were heavy soda consumers. More of the heavy soda consumers were women than men. More were African American than non-Hispanic white. Some people favored sweetened tea or fruit juice.

The other finding was that gender and race were the best predictors of who would lose the most weight by swapping beverages. Males and non-hispanic whites tended to lose more.

Limitations

Of course, these findings have limitations. Such an exploratory analysis is good for generating a hypothesis, but not for proving the point. Plus, we have the problem of self-reported beverage consumption. Such measures can be biased by things like social desirability. Some people shade the truth when reporting what they drink.

Nonetheless, these data tell us that cutting caloric beverages might be helpful for some, but not for all, as a tool for reducing obesity. One size will never fit all for nutrition, fitness, weight, and health.

Click here for the honors thesis by Vasa and here for the original publication of the CHOICE study.

Water, Ice, and Lemon; photograph © Jo Zimny Photos / flickr

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December 1, 2019