Diet, Protein-Restricted

OBJECTIVE: To determine the use of alternative diets and other alternative treatments in 2002 compared to 1999. DESIGN: Descriptive, questionnaire. METHOD: During the period 13-26 May 2002 a survey was held among all patients visiting the outpatient clinic of the Netherlands Cancer Institute/Antoni van Leeuwenhoek hospital, Amsterdam, the Netherlands. Patients were asked about their current and past use of alternative therapies, their reasons for using these therapies, the way they were informed about these therapies and the expenses involved.

Fetal growth and development is dependent upon the nutritional, hormonal and metabolic environment provided by the mother. Any disturbance in this environment can modify early fetal development with possible long-term outcomes as demonstrated by extensive work on 'programming'. Growth restriction resulting from a deficit in tissue/organ cell number (as measured by tissue DNA content) is irrecoverable. However, when the cell size (or cell protein content) is reduced, the effects on growth may not be permanent.

Caloric restriction (CR) decreases aging rate and mitochondrial ROS (MitROS) production and oxidative stress in rat postmitotic tissues. Low levels of these parameters are also typical traits of long-lived mammals and birds. However, it is not known what dietary components are responsible for these changes during CR. It was recently observed that 40% protein restriction without strong CR also decreases MitROS generation and oxidative stress.

Components of the diet related to changes in eating habits that characterize the modern Western world are important factors in the increasingly high prevalence of chronic disease, including obesity, diabetes, hypertension and as a consequence, chronic kidney disease. The healthy diets recommended for the general population to promote longevity (such as the Mediterranean diet), are defined based on epidemiological and intervention studies and are usually characterized by a relatively higher amount of protein than the usual Western diet.

Studies on the relationship between oxidative stress and ageing in different vertebrate species and in calorie-restricted animals are reviewed. Endogenous antioxidants inversely correlate with maximum longevity in animal species and experiments modifying levels of these antioxidants can increase survival and mean life span but not maximum life span (MLSP).

In laboratory animals, calorie restriction (CR) protects against aging, oxidative stress, and neurodegenerative pathologies. Reduced levels of growth hormone and IGF-1, which mediate some of the protective effects of CR, can also extend longevity and/or protect against age-related diseases in rodents and humans. However, severely restricted diets are difficult to maintain and are associated with chronically low weight and other major side effects.

Dietary restriction extends lifespan in a variety of organisms, but the key nutritional components driving this process and how they interact remain uncertain. In Drosophila, while a substantial body of research suggests that protein is the major dietary component affecting longevity, recent studies claim that carbohydrates also play a central role. To clarify how nutritional factors influence longevity, nutrient consumption and lifespan were measured on a series of diets with varying yeast and sugar content.

OBJECTIVE: To determine the prevalence of use of alternative diets and other alternative therapies by cancer patients DESIGN: Descriptive, questionnaire. METHOD: During one week, a written survey was held among all 429 patients visiting the outpatient cancer clinic of the Antoni van Leeuwenhoek hospital, Amsterdam, the Netherlands. Patients were asked about their use of alternative therapies both current and in the past, their reasons for using these therapies and the extra expenses involved. A total of 405 patients participated in the study.