The objective was to compare the effect of dairy and nondairy beverages when consumed with carbohydrate at breakfast on subjective appetite, food intake (FI), and postprandial glycemia (PPG) in healthy young adults. Twenty-six healthy males and females (13 males and 13 females; 23.0 ± 2.6 years; BMI: 22.3 ± 1.5 kg/m) participated in a randomized crossover study. They consumed nonisocaloric amounts (250 mL) of almond beverage, soy beverage, 1% fat milk, yogurt beverage, and water (control) with cereal and 120 min later, an ad libitum meal. Subjective appetite, PPG, and insulin were measured at baseline and at intervals before and after the meal at which FI was measured. Post-treatment blood glucose was lowest following soy beverage compared with all treatments but was not different from milk (p = 0.0002). There were no differences between any other treatments. However, over the first hour, PPG for all treatments was 27% lower compared with water (p < 0.0001). Milk and yogurt beverage led to the highest insulin concentrations post-treatment (p < 0.0001) but there were no differences between treatments postmeal. All treatments reduced appetite and led to lower FI at the meal compared with water, but FI was lower after milk compared with all treatments except yogurt beverage (p < 0.0001). Both dairy and nondairy beverages consumed with a high glycemic cereal at breakfast increased satiety and decreased FI compared with water with cereal. Despite higher carbohydrate content, all beverages led to similar or lower PPG than the water breakfast, but dairy beverages increased insulin more than nondairy beverages.

The objective was to compare the effect of liquid, semi-solid, and solid dairy products and a nondairy beverage when consumed with glycemic carbohydrate on subjective appetite, food intake (FI), and post-prandial glycemia (PPG) in healthy older adults. Thirty healthy men and women (14 males and 16 females; age: 64.6 ± 2.4 y; BMI: 25.6 ± 2.5 kg/m) participated in a randomized crossover study. Treatments were one of 250 mL of 2% fat milk and soy beverage, 175 g of 2% Greek yogurt, and 30 g of Cheddar cheese consumed as part of an isocaloric (380 kcal) meal with bread and jam. Water alone served as the energy-free control for subjective appetite. At 180 min after consumption, the participants were fed an ad libitum meal to measure FI. Subjective appetite, blood glucose, and insulin were measured at baseline and at intervals both before (post-treatment) and after the meal (postmeal). Cheese and yogurt resulted in lower post-treatment blood glucose than milk and soy beverage when consumed with carbohydrate (p < 0.0001), but no differences among any treatments were observed postmeal. Treatments led to similar insulin concentrations. Post-treatment appetite was lower than after the water control for all treatments but suppressed more by cheese and yogurt compared with milk (p < 0.0001). There were no differences in FI among treatments. Cheese and yogurt increase satiety and lower PPG more than milk or a soy beverage when consumed with carbohydrate.

Dairy proteins reduce appetite and improve postprandial glycaemic response in adults. However, there are no reports of dairy in amounts usually consumed on satiety and postprandial glycaemia in either young or older adults. In a randomized crossover design, 30 healthy young adults (age: 23.5 ± 0.5 years; body mass index (BMI): 21.8 ± 0.4 kg/m2) and 30 healthy/overweight older adults (age: 65.2 ± 0.5 years; BMI: 24.7 ± 0.6 kg/m2) consumed 1 serving (according to manufacturers’ labels) of skim milk (0.1% milk fat (MF)), whole milk (3.25% MF), plain Greek yogurt (2% MF), cheddar cheese (31% MF), and water (energy-free control) after a 12-h fast. Subjective appetite was measured every 15–30 min over 3 h. Blood glucose and insulin were measured at baseline and every 15–30 min over 2 h. All dairy treatments reduced post-treatment subjective appetite area under the curve (AUC) over 3 h by 8%–17% more than water. Greek yogurt reduced appetite 3-h AUC more than skim and whole milk by 9% and 7%, respectively (p < 0.0001). Post-treatment blood glucose 2-h AUC was 42% lower in young compared with older adults (p = 0.003). It was also 52%–78% lower after cheese compared with milks and yogurt (p < 0.0001). Post-treatment insulin AUC after cheese was only 10%–15% of that after milks and Greek yogurt (p < 0.0001). We conclude that single servings of dairy differ in effect on postprandial satiety and glycaemia and merit consideration in management of metabolic syndrome.