Randomised crossover study to investigate whether patients eat more when food is served on a red plate

Abstract

Malnutrition is well recognised in elderly patients with hip fractures and is an important challenge [1]. Cognitive impairment and delirium are common in this patient group. Visual acuity and visual contrast sensitivity decline with ageing [2]. These factors put hip fracture patients at significant risk of consuming less than their optimal nutritional intake. Poor nutritional status is associated with a less favourable outcome following hip fracture [3]. Patients on a hip fracture unit with an Abbreviated Mental Test Score (AMTS) < 7 were shown to eat 30% more lunch from a red plate compared to a white plate [4]. Similar results were observed in a small group of patients with advanced Alzheimer's disease living in a care home [5]. 99 post-operative hip fracture patients participated in this 6-day crossover study. Patients were randomised to either red or white plates. In arm 1 of the study (first 3 days), patients in group A were served food on red plates and patients in group B on white plates. In arm 2 (subsequent 3 days) patients were served food on the alternate colour plate. Dietary intake for breakfast, lunch and dinner was measured during the study period. Oral intake was calculated using weighed meal records and energy (kcal) intake was also calculated. There were 80 female and 19 male participants. Both groups: mean age was 83.9 years; mean AMTS was 7. Oral intake from red plates was 12% higher in arm 1 (p<0.05) but not overall significant in arm two, however group B showed an increased intake each consecutive meal once they switched to a red plate (arm 2). In patients with AMTS <7 (n=32) there was a 14% increase in oral intake from red plates (across both study arms). Total kcals consumed were generally in proportion to changes in weight of food eaten. This study supports previous research that meals served on red plates increase oral intake in patients recovering from surgery for a hip fracture. Increased oral intake was most marked in patients with cognitive impairment. Serving food on red plates offers a practical and inexpensive option to increasing nutritional intake in this vulnerable group. Further studies are needed to see if there are longer term benefits with regards to nutritional status, hospital readmissions and length of stay.