Nutrition and Aging Flashcards
Rate of aging -> age related diseases -> death
3 factors contribute -> genetics (senescence genes, genes coding for components of biomolecules defense systems), lifestyle factors (diet, housing, exercise), environment (exposure to chemicals, disease causing organisms)
Xenobiotic detoxification systems
activity of these enzymes declines with age
Disability threshold
Functional capacity of individual’s tissues and organs (lungs and kidney) may develop and decline at different rates -> below this point there is a functional disability -> different people reach this at different stages
Total dysfunction of the lung
normally occurs at 130-140 years old, this number is lowered by ROS, smoking, COPD (lungs reach maturity at 18-25 years)
Frailty
ability to withstand challenges -> in between senility and death
Programmed aging
aging theory that says that limited number of cell divisions and neuroendocrine and brain function decrease
Inefficient DNA repair
aging theory that says over a lifetime -> proportion of cells carrying abnormal DNA increases
Free radical damage
aging theory that says there is a decreased efficiency of free radical scavenging systems as we age
Summation of cumulative damage to life systems sustained throughout lifetime
aging theory that says accumulation of damaged cell lipids and proteins and raised levels of oxidant and inflammatory stress (increase in CRP)
Programmed cellular aging
majority of our cells initially contain telomeres of a certain length -> with each cell division this length is diminished by a fixed amount
Cardiovascular changes with aging
atherosclerosis, hypertension
Central nervous system changes with aging
reduced cognitive function
Musculoskeletal changes with aging
skeletal muscle atrophy, osteoporosis
Respiratory changes with aging
reduced lung volume, obstructive pulmonary disease
Endocrine changes with aging
non-insulin dependent diabetes, hypercortisolemia
Immune changes with aging
generally decline in function -> especially T cells
Factors leading to increased morbidity and mortality in the elderly
sarcopenia, malnutrition and frailty (all inter-related)
Frailty
clinical syndrome characterized by at least 3 of the following criteria -> weight loss, self reported exhaustion, weakness (fall in hand grip strength), slow walking speed, low physical activity
Sarcopenia
excessive loss of skeletal muscle -> impairment in activities of daily living, loss of strength, increased incidence of falls, increased incidence of hip factors, calf circumference < 31cm