A Diet Containing Animal Source Protein as Fresh, Lean Beef Is More Well Liked and Promotes Healthier Eating Behavior Compared with Plant-Based Alternatives in Women with Overweight

Background

Despite limited evidence from intervention trials, replacing animal-source protein-rich foods with plant alternatives continues to be recommended as part of a healthy dietary pattern.

Objectives

The objective of this study was to examine whether a diet containing fresh, lean beef elicits greater satiety, reduces ad libitum food intake, and is more acceptable compared with a diet containing plant alternatives in women with overweight.

Methods

Seventeen women with overweight (mean ± SEM, age: 33 ± 1 y; BMI: 27.8 ± 0.1 kg/m²) completed an acute, tightly controlled, crossover design study. Participants were provided with eucaloric, isonitrogenous diets (15% of daily intake as protein) containing either 2 servings/d of fresh lean beef (BEEF) or plant equivalents (PLANT) for 7 d/pattern. During day 6 of each pattern, the participants completed a 10-h controlled-feeding, clinical testing day, which included repeated appetite and satiety questionnaires and blood sampling to assess pre- and postprandial plasma peptide YY (PYY) and GLP-1 across the day. On day 7, the participants completed a free-living testing day in which they consumed their respective protein foods and were provided with additional carbohydrate- and fat-rich foods to consume, ad libitum, during each eating occasion. Energy and macronutrient composition were assessed. A 2- to 3-wk washout period occurred between patterns.

Results

No differences in daily satiety were detected between patterns. During the ad libitum testing day, 24-h food intake was not different between patterns (BEEF: 2714 ± 219 compared with PLANT: 2859 ± 147 kcals/d), BEEF led to fewer carbohydrates consumed compared with PLANT (338 ± 34 compared with 370 ± 22 g/d, P < 0.05), especially as sugar (169 ± 73 g compared with 186 ± 57 g, P = 0.05). Furthermore, BEEF was more well liked (i.e., higher flavor, texture, and acceptability) compared with PLANT (all, P < 0.05).

Conclusions

Although satiety was similar between patterns, the consumption of animal-source protein-rich foods, such as fresh and lean beef, was more well liked and resulted in voluntary reductions in total carbohydrate and sugar intake in middle-aged women with overweight during a single ad libitum testing day.

This study was registered at clinicaltrials.gov as NCT02614729.