Effectiveness of nutritional intervention provided to older people and nutrients indicating food insecurity in primary care settings in Tehran: protocol of a prospective population-based cohort study.

Background and aim: With the growing older population, ensuring effective, accessible nutritional support within primary care as a first line of medical care is becoming increasingly important. Nutritional counselling is a promising approach to enhancing health outcomes and independence among older adults. However, a stronger evidence base is needed to assess its true effect and inform clinical decisions. Additionally, food insecurity remains an under-recognised issue in this population and is often overlooked in primary care settings. This highlights the need for simple, practical methods to identify those at risk. This study aimed to assess the effectiveness of nutritional intervention provided to older people and determine which nutrients may indicate food insecurity in primary care settings in Tehran.

Methods: The study will be conducted in two phases. The first phase is a prospective cohort study (single cohort). The second phase is a cross-sectional study on older people who refer to primary care settings affiliated with the Tehran University of Medical Sciences. In the first phase, the effectiveness of nutritional interventions - including counselling and diet - is evaluated based on anthropometric indicators (weight, waist circumference, calf circumference, arm circumference and waist-to-height ratio), blood pressure and scores from the Mini Nutritional Assessment, health-related quality of life, dietary intake and physical activity. Assessments will be evaluated prospectively at the beginning of the study, after 3 months, and at the end of the study. In the second phase of the cross-sectional study, by examining dietary intake and food insecurity, we will identify the specific nutrient or food group that serves as an indicator of food insecurity in the diet of older individuals. Intakes below 50% and 75% of the recommended daily allowance will be analysed. Through sensitivity and specificity analysis, we will identify which nutrient or food group is strongly associated with food insecurity in older people.

Ethics and dissemination: This study received approval from the Medical Ethics Committee of Tehran University of Medical Sciences, Tehran, Iran (IR.TUMS.MEDICINE.REC.1402.474). Study findings will be disseminated through peer-reviewed journal articles, presentations at national and international conferences and meetings with the Iranian Ministry of Health, facility and community stakeholders.

Registration number: 69772.