OBJECTIVE To investigate the relationships between nutritional status measured by a comprehensive nutritional assessment including anthropometric measurements, nutritional biological markers, evaluation of dietary intake, and the Mini-Nutritional Assessment (MNA) nutrition screening tool. METHODS A prospective study. METHODS One hundred fifty-five older subjects (53 men and 102 women; mean age = 78 years; range = 56-97 years). These participants were hospitalized in a geriatric evaluation unit (n = 105) or free living in the community (n = 50). METHODS Weight, height, knee height, midarm and calf circumferences, triceps and subscapular skinfolds, albumin, transthyretin (prealbumin), transferrin, ceruloplasmin, C-reactive protein, alpha1-acid glycoprotein, cholesterol, vitamins A, D, E, B1, B2, B6, B12, folate, copper, zinc, a 3 day food record combined with a food-frequency questionnaire; the MNA nutritional screening. RESULTS The MNA scores have been found to be significantly correlated to nutritional intake (P < .05 for energy, carbohydrates, fiber, calcium, vitamin D, iron, vitamin B6, and vitamin C), anthropometric and biological nutritional parameters (P < .001 for albumin, transthyretin, transferrin, cholesterol, retinol, alpha-tocopherol, 25-OH cholecalciferol zinc). An MNA score between 17 and 23.5 can identify those persons with mild malnutrition in which nutrition intervention may be effective. CONCLUSIONS The MNA is a practical, noninvasive, and cost-effective instrument allowing for rapid nutritional evaluation and effective intervention in frail older persons.