The Impact of Nutritional Status on Oral Health Outcomes and Management in Older Adults: A Systematic Review and...

This systematic review and meta-analysis evaluated the relationship between nutritional status and the oral health of older adults (aged 75 years or older). The PECO focus question was, 'What is the occurrence, association and impact of nutritional state on the oral health outcomes and its management in older adults?'

A comprehensive literature search was performed across MEDLINE (PubMed), Embase and the Cochrane Library. Publications up to April 2025 were considered, yielding 3324 records for initial screening. Quality assessment of the included studies predominantly revealed a low to moderate risk of bias.

Eighty-three studies were included for data analysis. Meta-analyses demonstrated that older adults at risk of malnutrition had fewer teeth (SMD = -0.29; 95% CI: -0.46, -0.11; p = 0.002). Those with < 20 teeth and who were not rehabilitated with dentures were more likely to be malnourished (OR = 4.00; 95% CI: 1.21, 13.18; p = 0.02). Malnutrition was associated with self-reported chewing problems (OR = 2.38; 95% CI: 1.74, 3.26; p < 0.0001), swallowing problems (OR = 3.18; 95% CI: 2.20, 4.61; p < 0.0001) or dry mouth (OR = 2.35; 95% CI: 1.91, 2.88; p < 0.0001). Conversely, those with oral pain showed lower odds of malnutrition risk (OR = 0.68; 95% CI: 0.52, 0.89; p = 0.005).

Fewer teeth, existing chewing or swallowing problems, dry mouth and the absence of removable dentures where needed, were associated with malnutrition in care-dependent older adults. The current lack of longitudinal studies and proof of causality for malnutrition affecting oral health outcomes underscores the need for further research to better clarify the complex relationship between oral health and nutrition in older populations.

PROSPERO Registration: CRD420251003549.