Wenhold, F.A.M. (Friedeburg Anna Maria)2021-11-022021-11-0220212020*A2021http://hdl.handle.net/2263/82473Thesis (PhD (Dietetics))--University of Pretoria, 2020.Introduction The high prevalence and impact of dementia call for preventative measures, including application of an optimised diet. Omega 3 polyunsaturated fatty acids (PUFA) may influence the risk for developing dementia by supporting cardiovascular health and by decreasing inflammation. Research, particularly randomised controlled trials, studying a food-based approach that uses Omega 3 PUFA intake from foods such as fish to counteract dementia in low/middle income countries (LMIC), is lacking. Aim To determine the effect of supplementing diets of independently living, resource-limited elderly participants for 12 weeks with fish versus non-fish foods on cognition. Methods In a randomised controlled trial the usual diet of independently living elderly persons in a resource-limited retirement centre in urban South Africa was enhanced with contextappropriate foods i.e. canned baked beans, canola oil and peanut butter mimicking elements of the Mediterranean-Dietary Approaches to Stop Hypertension (DASH) Intervention for Neurodegenerative Delay (MIND) diet. Additionally, the intervention group received canned pilchards and fish spread (equivalent to a calculated daily intake of 2.2g Omega 3 PUFA) weekly compared to canned meatballs and texturised soya protein (meat substitute) received by the control group. Cognition and level of functioning were measured before and after intervention with the Cognitive Abilities Screening Instrument (CASI) and the Lawton Instrumental Activities of Daily Living (IADL). Adherence was assessed by determining dietary intake with a study-specific food frequency questionnaire (FFQ) and red blood cell (RBC) PUFA biomarkers before and after the intervention. Data were analysed by non-parametric analysis of covariance (ANCOVA) with, and without, bootstrap imputation. Results Fifty seven (74% female, mean age: 72 ±7 years) elderly participants participated in this study. There was a significant post intervention difference (P=0.036) in the total CASI scores between the intervention and control groups, when the model was fitted with imputation and controlled for baseline scores. The predicted total CASI score of the intervention group was higher than the score of the control group. Likewise the calculated dietary Omega 3 PUFA intake and red blood cell (RBC) Eicosapentaenoic acid (EPA) and Docosapentaenoic acid (DPA) content differed significantly between the intervention and control group after the intervention phase. The Lawton IADL presented similar results over the course of the study with limited variance. Conclusion Fish intake in the context of the MIND diet may exert a positive effect on cognition as the current study showed that fish can have a significant effect on the cognition of resource-limited elderly after 12 weeks of supplementation of an enhanced diet.© 2021 University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria.UCTDThesis