Process of ageing

Normal and Therapeutic Nutrition 3(2+1)
Lesson 17:Old Age–Nutritional Requirement

Process of ageing

  • Tissue damage by free radicals and pro-oxidant radicals like superoxide, peroxide and hydroxyl radicals is the basis for inflammatory and degenerative changes seen in variety of diseases like cancer.
  • Endogenous antioxidants are superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX) which act together with glutathione reductase and NADPH. With age and in diseased conditions these antioxidant defences are lowered and the vitamins A, C and E get excessively utilized and a deficiency state occurs.
  • The process of ageing brings about physiological, psychological and immunological changes which influence the nutritional status. The changes associated with ageing are partly influenced by genetics, race and gender.

As part of ageing process the functioning of the organ may change which may influence the nutrient status as given in

Table: Changes in organ functioning with ageing that may influence nutrient requirements

Organ function Changes Effect on nutrition
Taste & Smell Decreased taste buds & papillae on tongue Loss of ability to detect sweet and salt

Decreased taste, olfactory nerve endings Decreased palatability causing poor food intake

Decreased sensory stimulation, impairs metabolic process
Salivary glands Decrease in salivary secretion, dry mouth, xerostomia Difficulty in chewing and swallowing makes them avoid certain foods. crunchy, dry and sticky foods
Teeth Loss of teeth and wearing dentures Decreased consumption of meat and fresh fruits and vegetables. Results in inadequate intake of energy, iron and vitamin C, folate and ?-carotene.
Gastric function and emptying Decreased secretion of HCl, intrinsic factor and pepsin Decreased bioavailability of minerals, vitamins and proteins

Rapid rate of emptying of fluids Above 60 years of age Decreased absorption of protein bound vitamin B12, folate

Increased proximal small bowel Ph and bacterial overgrowth in bowel Increased bacterial folate synthesis, counteracts malabsorption

Decreased calcium absorption Poor vitamin- D status
Small intestine Decreased secretion of lactase
Constipation – prolonged recto-sigmoid transit
Risk factor for developing oesteoporosis
Liver & biliary function Decreased size and blood flow Decreased rate of albumin synthesis

Minor structural and biochemical changes

Gall bladder becomes sluggish in releasing bile Susceptible to gall stones

Reduced activity of drug metabolising enzymes Drug dosage may lead to lower enzymes
Metabolic function Impaired glucose tolerance Need dietary modifications, exercise and oral pharmacologic agents

Decreased metabolic rate due to change in body composition, physical activity and body proteins Decreased energy requirements
Cardio vascular function Blood vessels become less elastic, increase in total peripheral resistance Prevalence of hypertension, modification of diet accordingly
Neurological function Confusional state Decreased synthesis of seretonine, carnitine from amino acid lysine, methionine

Carotenoids play protective role in aging problems
Immuno competence Declines with age Supplementation with vitamin – E, zinc & PUFA
Psychological factors Depression

Affects appetite, digestion, energy level, weight and well being

Last modified: Monday, 24 October 2011, 9:57 AM