Dietary protein intake, protein sources & distribution patterns in community-dwelling older adults: A harmonized analysis of eight studies.

Objectives: Sufficient protein intake is important for older adults to prevent sarcopenia. Better insight into dietary characteristics may be helpful to improve daily protein intake. Therefore, this study aimed to compare characteristics of community-dwelling older adults with distinct amounts of daily protein intake.

Methods: Baseline data of older adults (age >55 years) from eight intervention studies were pooled. Protein intake was measured using 24-h recalls or 3-day food records. Participants were stratified into one of four different groups based on their habitual protein intake (<0.8 g per kilogram bodyweight per day (g/kg/d), 0.8-0.99 g/kg/d, 1.0-1.2 g/kg/d and >1.2 g/kg/d). Protein intake per meal, animal-versus plant-based protein intake, daily protein distribution patterns (e.g. spread or pulse) and the protein intake from distinct protein-rich food categories (meat, fish, dairy, grains and others) were assessed.

Results: Among 814 participants (69 ± 9 years, 54 % male), mean protein intake was 0.98 ± 0.30 g/kg/d. 28 % (n = 227) of the population had a protein intake <0.8 g/kg/d, 29 % (n = 240) 0.8-0.99 g/kg/d, 22 % (n = 179) 1.0-1.2 g/kg/d and 21 % (n = 168) >1.2 g/kg/d. Higher protein intake groups had a lower body weight and BMI and a higher energy intake per day. Although protein intake distribution patterns did not differ across groups, meals with >20 g or >0.4 g protein per kilogram bodyweight per meal more often occurred in the higher protein intake groups. Protein intake was the lowest at breakfast followed by lunch and dinner, in all groups. Higher protein intake groups consumed a higher proportion of animal-based protein sources.

Conclusion: Distinct protein intake groups showed comparable intake distribution patterns, with lowest protein consumption at breakfast and highest at dinner. Nevertheless, the highest protein intake group more often consumed >20 gr of protein per meal, indicating that a focus on the absolute amount of protein per meal, particularly at breakfast, could further optimize daily protein intake in older adults.