Obesity is associated with an increased risk of morbidity and mortality; however, data suggest that in old age, obesity is not detrimental. The study’s objective was to verify whether obesity frequency still increases in Polish Caucasian seniors and to verify the “obesity paradox”. Five thousand and fifty-seven community-dwelling individuals aged ≥ 65 years completed a detailed medical questionnaire, underwent measurements of the body mass index (BMI) and the waist circumference (WC), and an evaluation of physical and cognitive performances. Over a decade, general obesity increased by 2.1%, mostly due to a 3.9% increase in men. Abdominal obesity increased by 1.0%, mainly due to males, in whom it increased by 3.9%. Obesity increased the risk of several aging-related diseases, but this effect was less pronounced in the oldest-old. Obesity did not adversely affect the physical and cognitive functioning or mortality. Through a multivariable analysis, the BMI and WC remained the independent predictors of the Katz Activities of Daily Living score (p < 0.001 and p < 0.05, respectively) and Mini-Mental State Examination score (both p < 0.001). The Kaplan−Meier survival curves revealed that overweight and obesity classes 1 and 2 were associated with the lowest mortality. Through a multivariable analysis, overweight, class 1 obesity, and abdominal obesity remained the independent predictors of a decreased mortality (all p < 0.001). In conclusion, we found that overweight and obesity are not detrimental in seniors, including the oldest-old. We suggest that the anthropometric values defining obesity should be modified for age-advanced people.
Keywords: Activities of Daily Living (ADL); Mini-Mental State Examination (MMSE); PolSenior; PolSenior2; abdominal obesity; aging; aging-associated diseases; mortality; obesity; obesity paradox.