Dietary Habits and Nutritional Status among Older Adults of Different Ethno-Religious Groups in Nigeria: A Systematic Review

Population ageing is associated with physiological, socioeconomic and social changes that influence food intake and nutritional wellbeing. Older adults are particularly vulnerable to malnutrition due to reduced appetite, impaired dentition, chronic diseases, functional limitations, poverty and food insecurity. To systematically review and synthesise evidence on dietary habits and nutritional status among older adults of different ethno-religious groups in Nigeria. The review was conducted and reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA 2020) guidelines. PubMed/MEDLINE, Scopus, Web of Science, CINAHL, African Index Medicus, African Journals Online and Google Scholar were searched for relevant studies published from database inception to 2026. Eligible studies included empirical research conducted among Nigerian adults aged 60 years and above that reported dietary habits, dietary intake, dietary diversity or nutritional status. Studies were screened against predefined eligibility criteria, and relevant data were systematically extracted. Methodological quality and risk of bias were assessed using appropriate critical appraisal criteria according to study design. Due to substantial heterogeneity in study populations, dietary assessment methods and nutritional indicators, findings were synthesised narratively. The included evidence comprised predominantly cross-sectional studies conducted among community-dwelling and institutionalised older adults across several Nigerian states. Findings demonstrated considerable variation in dietary practices and nutritional status. While many older adults consumed staple foods regularly, inadequate consumption of dairy products, fruits, vegetables and other nutrient-dense foods was reported in several settings. Nutritional assessments demonstrated the coexistence of underweight, malnutrition, overweight and obesity, indicating a double burden of malnutrition. Evidence directly comparing ethnic and religious groups was limited, although cultural dietary practices and religious practices were identified as potentially important influences. Older Nigerians experience substantial dietary and nutritional vulnerabilities.