Pairing Sugary Drinks With High-Protein Food Might Make You Fat

24th July 2017

By Harriet Mallinson | Published on July 24, 2017

A soda or fruit drink might seem like a tasty accompaniment to your post-workout dinner but consuming a sugar-sweetened drink with a protein-rich meal could be making you fatter.

A study has shown that twinning a sugar-sweetened drink with a high-protein meal may negatively affect energy balance, alter food preferences and cause the body to store more fat.

Sugar-sweetened beverages are any liquids sweetened with various forms of added sugars, such as brown sugar, corn sweetener, corn syrup, dextrose, fructose, glucose, high-fructose corn syrup, honey, lactose, malt syrup, maltose, molasses, raw sugar, and sucrose.

Examples include regular soda, fruit drinks, sports drinks, energy drinks, sweetened waters, and coffee and tea with added sugars.


What did the scientists do?

The researchers in the study, published in the journal BMC Nutrition, examined 27 healthy-weight adults (13 male, 14 female), who were on average 23 years old.

Scientists analysed how their bodies responded when sugar-sweetened drinks were imbibed with food. They found that the inclusion of a sugar-sweetened drink decreased fat oxidation, which kick-starts the breakdown of fat molecules, after a meal by 8%.

“We found that about a third of the additional calories provided by the sugar-sweetened drinks were not expended, fat metabolism was reduced, and it took less energy to metabolize the meals,” said Dr Shanon Casperson, lead author of the study from The Grand Forks Human Nutrition Research Center, US, said. “This decreased metabolic efficiency may ‘prime’ the body to store more fat.”


– RELATED: Is Fizzy Water Really Causing Obesity? –


Study participants made two 24-hour study visits to the center, eating two 15% protein meals (breakfast and lunch) after an overnight fast on one visit and two 30% protein meals after an overnight fast on the other visit.

The increase in protein was counterbalanced by a decrease in carbohydrates. All meals were composed of the same foods and they provided 17g of fat and 500 kcals. Participants consumed a sugar-sweetened drink with one of the meals and a non-sugar sweetened drink with the other meal.


What was the outcome?

The results proved that if a sugar-sweetened drink was consumed with a 15% protein meal, fat oxidation decreased by 7.2g on average. If a sugar-sweetened drink was consumed with a 30% protein meal, fat oxidation decreased by 12.6g on average.

While having a sugar-sweetened drink increased the amount of energy used to metabolise the meal, the increased expenditure did not even out the consumption of additional calories from the drink.

Dr. Casperson said: “We were surprised by the impact that the sugar-sweetened drinks had on metabolism when they were paired with higher-protein meals. This combination also increased study subjects’ desire to eat savory and salty foods for four hours after eating.”

The researchers used a room calorimeter, a 25m3 furnished chamber that measures movement, oxygen, carbon dioxide, temperature and pressure, to assess how dietary changes affected energy expenditure and the way nutrients were processed by the body.

By having study participants stay in a room calorimeter, researchers can determine how many grams of carbohydrate, protein and fat they are using and how many calories they are burning every minute.  Study participants stayed inside the room for the duration of each study visit.

Dr. Casperson said: “Our findings suggest that having a sugar-sweetened drink with a meal impacts both sides of the energy balance equation. On the intake side, the additional energy from the drink did not make people feel more sated. On the expenditure side, the additional calories were not expended and fat oxidation was reduced.

“The results provide further insight into the potential role of sugar-sweetened drinks – the largest single source of sugar in the American diet – in weight gain and obesity.”


How bad are sugary drinks?

In the US, according to the Centers for Disease Control and Prevention, youths consume 143 calories from sugary drinks while adults consume 145 calories on a given day on average. A study in The Lancet revealed that each 12-ounce soft drink per day consumed by children increases their odds of becoming obese by 60%. An average adult would need to walk at a moderate pace for 25 minutes to burn off 12-ounce can of soda.

If you’re a big fan of sugar-sweetened beverages why don’t you try switching to healthier alternatives. You can add freshly squeezed lemon or orange juice to plain water or sparkling water or add slices of fruit to water for a similar fizzy kick.