Low protein content of plant-derived nutrition limits the protein transition in hospitalized patients: Results from an observational study

Background & aims

To improve global- and environmental health, the Dutch Green Deal Sustainable Healthcare (DGD) guidelines recommend to replace at least 50 % of animal protein with plant-derived protein. This may be a challenge for hospitalized patients due to the low protein content and the lack of Essential Amino Acids (EAA) in individual plant-derived sources in combination with anabolic resistance during disease. Yet, there is little knowledge about the effect on protein- and amino acid intake among hospitalized patients as we shift to more plant-derived diets. Therefore, this observational study examines (plant- and animal) protein intake and Amino Acid Scores (AAS) of predominantly plant- and animal derived meals in a large university hospital.

Methods

Food intake data were collected through direct observation in non-critically ill adult patients between October and November 2023. Protein requirements were set on 1.2 g/kg body weight, adjusted for BMI. For data analysis, patients were divided into three groups based on their total protein intake: low (<0.8 g/kg), moderate (0.8–1.1 g/kg) and adequate (≥1.2 g/kg). Meals were considered predominantly plant-derived if plant protein (in grams) accounted for over 50 % of its total protein content. AAS were determined per meal by assessing the amount of EAA per gram of protein relative to EAA requirements.

Results

In total, 234 patients were included. Protein intake was insufficient in 80 % of all patients. The overall animal-to plant protein ratio was 69:31. Among patients who consumed more than 50 % plant-derived protein per meal, lysine was the most common limiting amino acid (AAS <1). In contrast, no limiting AAS per gram of protein were found for patients consuming more than 50 % animal-derived protein per meal.

Conclusion

Achieving sufficient protein intake (1.2 g/kg) is a key challenge especially in the shift towards more plant-derived nutrition. Although the predominantly plant-derived meals require careful attention to amino acid profiles, especially for lysine, the low total protein content of predominantly plant-derived meals poses the greatest challenge, thereby limiting the feasibility of the protein transition for hospitalized patients.