Posted Sep 6 , 2017 02:36 PM

Postprandial energy metabolism and substrate oxidation in response to the inclusion of a sugar- or non-nutritive sweetened beverage with meals differing in protein content

Casperson SL, et al. BMC Nutrition 2017;3:49

What were the findings (excerpted from the Abstract)?

The macronutrient composition of the diet may play a more important role in maintaining a healthy body weight and preventing obesity than previously thought. The primary goal of this research was to determine the extent to which the simple addition of a small serving of a sugar sweetened beverage (SSB) to meals with different macronutrient compositions impacts appetite, energy metabolism and substrate oxidation. Appetite, energy metabolism and substrate oxidation were measured in 27 healthy weight adults (age = 23 ± 5 y; BMI = 23 ± 2 kg/m2) on two occasions in a room calorimeter after consuming a SSB or a non-nutritive sweetened beverage (NNSB) with a standard (15% of energy intake [E]) or high-(30%E) protein meal. Meal carbohydrate (CHO) content was adjusted to maintain equivalent calories for both study visits. All meals were composed of the same foods and provided 17g of fat and 500 non-beverage calories. Study visits were separated by at least 1 week and menstruating females were studied during the luteal phase (Days 15–20). The effects of sex, protein level and beverage type and their interactions on satiety, appetite for foods with specific taste profiles, diet-induced thermogenesis (DIT) and rates of substrate oxidation were assessed using Analysis of Variance. Increasing dietary protein decreased hunger and increased satiety. Males were hungrier and less satisfied with the meals than females. Increasing dietary protein also decreased the desire to eat something savory, salty and fatty and the males had a greater appetite for food with these taste profiles. Interestingly, there was no effect of sex, dietary protein or beverage type on the desire to eat something sweet. The inclusion of a SSB markedly suppressed DIT (2.42% ± 5.91%) and fat oxidation (9.87 ± 11.09 g). These findings confirm that appetite sensations, food preferences, energy expenditure and substrate oxidation are significantly altered in response to changes in meal macronutrient composition produced by modifications in the protein content of a meal and consumption of a SSB. Most notably, consumption of a SSB during a meal markedly reduces energy efficiency and fat oxidation independent of macronutrient composition.

Why is this important?

While it should come as no surprise that sugar can add fat, it is a surprise that the sugar in a beverage (the size and sugar content roughly equivalent to a can of sugared soda) can alter the ability to handle fat that is taken in the diet. This effect was clearly seen in just a single meal. The effect of sugar has a significant impact on fat metabolism which suggests more of a negative effect on metabolism than just the added calories. Also, this study suggests that increasing protein had more of an effect on the perceptions around food intake by lowering hunger and increasing measures of satiety following the meal. The national movement to lower the intake of sugar sweetened beverages may well have even more of an impact than simply lowering overall calorie intake. Do you ask your patients about their intake of sugar sweetened beverages? Based on this new information will you counsel against intake of these beverages in the future?

Read the Article: