Purpose Accurate height and weight measurement can be challenging in older adults and complicates nutritional status assessment. Other parameters like the neutrophil-to-lymphocyte ratio (NLR) and the lymphocyte count (LC) could be an option to these measurements. We aimed to test these variables as subrogates of body mass index (BMI) or calf-circumference (CC) for malnutrition screening in community-dwelling older adults. Methods This is a secondary analysis from the Salud, Bienestar y Envejecimiento (SABE) survey from Ecuador (2009). Includes data on demographics, health-related factors, physical assessments, and complete blood count, allowing to calculate NLR and LC to be used as part of the Mini Nutritional Assessment (MNA), instead of the BMI. Consequently, 4 models were included: standard MNA, MNA-CC, MNA-NLR and MNA-LC. Finally, age, sex, and comorbidities were considered as confounding variables. Results In our analysis of 1,663 subjects, 50.81% were women. Positive correlations with standard MNA were found for MNA-NLR (Estimate = 0.654, p  < 0.001) MNA-CC (Estimate = 0.875, p value < 0.001) and MNA-LC (Estimate = 0.679, p  < 0.001). Bland-Altman plots showed the smallest bias in MNA-CC. Linear association models revealed varying associations between MNA variants and different parameters, being MNA-NLR strongly associated with all of them (e.g. Estimate = 0.014, p  = 0.001 for albumin), except BMI. Conclusion The newly proposed model classified a greater number of subjects at risk of malnutrition and fewer with normal nutrition compared to the standard MNA. Additionally, it demonstrated a strong correlation and concordance with the standard MNA. This suggests that hematological parameters may offer an accurate alternative and important insights into malnutrition.