Date of Award


Document Type

Doctoral Thesis

Degree Name

Doctor of Philosophy


Biological Sciences

First Advisor

Dr Aoife McCarthy

Second Advisor

Dr Tara Coppinger


Aim: The primary aim of this thesis was to investigate the relationship between nutrition and frailty in Irish older adults. The nutritional status, dietary quality and perceived barriers/motivators to nutrition were also examined, and a frailty intervention protocol was designed. Methods: Cross-sectional study in Irish community-dwelling adults aged ≥65 years. Nutritional status, dietary intake, functional mobility and food choice motivators/healthy eating barriers were assessed using the Mini Nutritional Assessment – Short Form (MNA-SF), a food frequency questionnaire (FFQ), the Timed Up and Go (TUG) test and a custom designed 2-item questionnaire, respectively. Frailty was defined as three or more of the following features; weight loss, weakness, slowness, exhaustion and low physical activity. A pilot study was designed for a nutrition education intervention arm to complement an existing physical activity programme to prevent frailty in Irish older adults. Results: The prevalence of malnutrition and frailty were 1.2% and 12.0%, respectively. Several micronutrient insufficiencies were observed. Dairy intake was inadequate and intake of sugars, fats and snacks were excessive. Intakes of fish/fish products and fruit and vegetables were significantly associated with a lower frailty score; while intake of potatoes, sugars, preserves and snacks and fats/oils were associated with higher frailty score (p < 0.05). A significant relationship was observed between physical activity and TUG time in both genders (p < 0.001), and between nutritional status and TUG time in female subjects, only (p < 0.05). The most prevalent healthy eating barriers were ‘lack of cooking skills’ (32.7%) and ‘lack of motivation/willpower’ (31.2%), which were significantly associated with unfavourable dietary habits (p < 0.05). The primary food choice motivator was ‘taste’ (84%), followed by ‘healthiness’ (68.8%). Being motivated by ‘healthiness’ was significantly associated with healthier dietary trends (p < 0.05). Conclusions: Dietary quality of this cohort was relatively poor, and public health interventions are warranted to improve dietary habits in this group. The findings suggest that nutritional considerations should feature in frailty prevention programmes, in addition to physical activity. Focussing on specific food groups may be key, as a significant relationship was observed between intake of specific food groups and frailty in Irish older adults, for the first time. Evaluation of the designed research-informed frailty intervention for feasibility and effectiveness would be valuable in guiding future practice.

Creative Commons License

Creative Commons Attribution 4.0 International License
This work is licensed under a Creative Commons Attribution 4.0 International License.

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