High protein food + a sugary drink = Unhealthy combo meal
Researchers from the US Department of Agriculture (USDA) found that consuming fizzy drinks together with foods such as meat and cheese may be a particularly unhealthy combination – and promote cravings for salty, savory foods.
The USDA research team, led by Dr. SL Casperson, noted that a third of the additional calories provided by the sugar-sweetened drinks were not burnt off, less fat from the food was broken down by the body and less energy was needed to digest the meal. These findings, they suggest, could ‘prime’ the body to actually store more fat. A sugar-sweetened drink consumed with a meal containing 15% protein reduced the amount of fat oxidized by an average of 7.2g. Fat oxidation is the process in which the body uses up stored fats to produce energy. If a sugar-sweetened drink was consumed with a 30% protein meal, fat oxidation decreased by 12.6g on average, Casperson stated.
The researchers evaluated 27 healthy weight adults (13 men and 14 women) who were, on average, 23 years. All the participants spent two 24-hour periods in a special ‘metabolic chamber’ comprising an airlock system to allow meal trays and other materials to be passed in and out. The sealed nature of the chamber allowed the scientists to assess how dietary changes affected energy expenditure, and the way nutrients were processed by the body.
During Day 1: the participants were given breakfast and lunch consisting of 15% protein meals after fasting the previous night. On Day 2, they had two 30% protein meals after fasting. The order in which the two protein levels were served was randomized.
All the meals were designed to provide 17g of fat and 500 non-beverage calories. The increase in protein was counterbalanced by a decrease in carbohydrates. The difference was that the participants had a sugar-sweetened drink with one of the meals and a non-sugar-sweetened drink with the other meal.
When the participants were fed more protein, they felt fuller and less likely to crave savory, salty and fatty foods. After being given a sugar-sweetened drink with their protein-based meal, the need for savory and salty foods returned.
Researcher Ian Johnson, PhD, stated, “The results do suggest a mechanism whereby consumption of sugary drinks with meals might interfere with the body’s ability to regulate energy intake, and eventually lead to weight gain.” However, he also noted that further work and greater length of observation is needed to confirm the findings.
Why is this Clinically Relevant?
These preliminary results demonstrate the effect of sugary beverage consumption on energy metabolism and food choices and adds to the mounting evidence that sugar sweetened beverage consumption can increase susceptibility for weight gain and fat accumulation, especially when paired with a high protein meal.
These data highlight the need to design strategies aimed at maximizing macronutrient balance instead of focusing on interventions that strictly target energy balance.