Restrictive diets in the elderly: never say never again?

Restrictive diets have long been an essential part of standard nutritional therapy for a wide range of diseases like obesity, diabetes, hyperlipidaemia, arterial hypertension and chronic renal failure. Although a relevant number of studies have been published in this field, most of these have concentrated on adults below age 65. Data on the effects of restrictive diets in older persons are still scarce. With increasing age, restrictive diets seem to be less effective with regard to relevant study endpoints like morbidity, quality of life and mortality. This applies in particular to chronic indications which are in most cases associated with additional co-morbidities. Here the focus shifts towards providing adequate nutritional intake rich in macro- and especially micronutrients and a diet that is also highly palatable as older individuals are at increased risk of becoming malnourished and sarcopenic. In this context, nutritional prevention and therapy are of utmost importance for maintaining quality of life. This review summarizes the present evidence for the application of restrictive diets in older persons and balances it against potential risks.