The researchers discovered that drinking a sugar-sweetened beverage significantly reduced diet-induced thermogenesis, or the amount of energy it takes to metabolise meals, and fat oxidation, a process which kick-starts the breakdown of fat molecules.
And the more protein they ate, the more their fat oxidation decreased. When the participants ate the meal with 15 per cent protein and drank the sugary drink, their fat oxidation decreased by 7.2 grams, compared to 12.6 grams when they ate the 30 per cent protein meal with the sugar-sweetened drink.
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“This decreased metabolic efficiency may ‘prime’ the body to store more fat,” said study author Dr Shanon Casperson.
Another problem: The added calories with a sugary beverage didn’t help the participants feel any less hungry later on. And while adding more protein helped decrease cravings for savory, salty and fatty foods, combining a sugar-sweetened beverage with the protein-rich meal actually increased the people’s desire for salty and fatty stuff later.
Bottom line: adding more protein to your diet is a golden rule of weight loss, as it increases satiety and makes you feel more satisfied.
But this study suggests adding sugary drinks can take away from those benefits. If you want to reap the high-protein rewards, you may want to stick with a glass of water with your meal instead.