At the heart of the obesity epidemic sweeping the United States, experts agree that sugary soft drinks high in calorie content are an unwelcomed part of any healthy dieting plan. A recent study conducted at the University of Bristol's Nutrition and Behaviour Unit (NBU) suggests that we tend to neglect the amount of calories in our meal plans that are attributed to drinks, including fruit juices and soda.

"Our work adds important context to a broader ongoing debate about the dangers of liquid calories,” Professor Jeff Brunstrom said in a statement. "Calories in soft drinks and calories in snack foods have a small but comparable effect on the expected satiation of meals. This is the first time that the expected satiation of soft drinks has been quantified and compared in this way."

Brunstrom and his colleagues asked study participants to complete an electronic match-fullness task that assessed how full they expected to be from a meal that either included a drink containing a high calorie count, a drink containing no or low calories, or a snack containing the same amount of energy as the drink with a high calorie count. The research team also took into account how the carbonation from soft drinks played a role in the level of fullness each participant expected.

Regardless of the carbonation from soda, participants considered meals served with a drink containing a high calorie count to be more filling that a meal served with water. Meals that were served with a snack in place of a drink high in calorie content led to the same expected feeling of satiation in participants. The U.S. Department of Agriculture (USDA) estimates that one out of every four Americans gets around 200 calories a day from sugary soft drinks.

According to the Centers for Disease Control and Prevention, sugar-sweetened soft drinks are defined as “liquids that are sweetened with various forms of sugars that add calories. These beverages include, but are not limited to, soda, fruit-ades and fruit drinks, and sports and energy drinks.” The average adults in the U.S. add a significant number of calories to their diet via drinks with high sugar and calorie content. Around 50 percent of Americans drink at least one sugary soft drink on a given day.  

Source: Brunstrom J, et al. At the Society for the Study of Ingestive Behavior Conference. 2014.