Ageing, its causes and effects on our body

  • Ageing simply means becoming older. There are lots of changes like physical, psychological and social changes occurring in human body over time.
  • It is not a disease but a natural biological process.
  • Successful ageing is defined not by longevity alone but also by sufficient physical, mental and social well-being.
  • Ageing can occur at different rates among the individuals or within an individual.
  • It is influenced by genetics, socio-economic condition, physiology and lifestyle of a person.
  • Ageing can be characterized by:
    • Cellular and physiological deterioration
    • Increased mortality with age following maturation
    • Increased vulnerability to disease
    • Decreased ability to adapt to stress
    • Impaired homeostasis

Causes of Ageing:

  • Collagen breakdown: The supportive tissue collagen of our skin when broken down continuously reduces the strength of skin and hence results in wrinkling and sagging of skin.
  • Photo Defense: Repeated exposure to ultraviolet light (UV radiation) from the sun accounts for almost 90% of symptoms of premature skin ageing
  • Oxidation: Free radicals which are highly reactive can damage important cellular structures found in every layer of the skin; hypodermis, dermis and epidermis.
  • Inflammation: Although it is helpful in the short term, excessive or chronic inflammation is one of the most common factors in early onset of skin ageing.
  • Diet and Glycation: Eating a diet high in sugar and refined carbohydrates can damage our skin over time. Glycation (Excess sugar or bodily glucose) causes the skins proteins (like collagen and elastin) to lose their ability to function normally and thus accelerates skin ageing.
  • Sleep habits: Sleep gives our body an opportunity to refresh and regenerate cells and hence, poor sleep quality is connected to increased signs of aging and a diminished skin barrier function.
  • Environment: Our skin when subjected to the toxins and pollutants in our daily environment can easily trigger and worsen pigment spots and wrinkles.
  • Stress: A stressful lifestyle can trigger an inflammatory response in our body, as well as hurt our sleep habits. Stress hormones and inflammation can age our body faster.
  • Alcohol and Caffeine intake: Drinking alcohol and consuming caffeine excessively dehydrates our body which over time can cause our skin to sag and lose its shape.

Effects of ageing:

  • Ageing has various physiological changes in our body:
  1. Changes in skin:
    • Skin is more easily damaged
    • Delayed wound healing
    • Decreased inflammatory response
    • Decreased protection from ultraviolet light
    • Wrinkling, sagging of skin , Skin easily stretched under low loads because of continuous breakdown of collagen
    • Loss of resiliency
    • Diminished absorption
    • Altered thermal regulation
    • Decreased sensitivity to pain and pressure
  2. Body composition:
    • Body weight decreases
    • Cellular mass decreases along with the decrease in mass of bones (skeleton)
    • Increase in fat content in the body
  3. Metabolic changes:
    • Impaired glucose tolerance
    • Decreased metabolic rate due to changes in body composition and reduction in physical activity
    • Body protein level decreases
    • Delayed drug clearing due to reduction in hepatic and renal elimination
    • Decreased in body heat production coupled with impairment of thermoregulatory vasoconstriction
  4. Neuromuscular system:
    • CNS: Decrease in nerve cell number
    • Decreased dopamine and increased muscular rigidity
    • PNS: Decreased vibratory sensation
    • Psychomotor response reaction time increases
    • Cognitive impairment: Delirium, dementia, depression, memory loss, Alzheimer’s
  1. Skeletal system:
    • Changes in bone density: 30% loss in skeletal muscle mass also called Sarcopaenia from 3rd to 8th decade. Functional sarcopenia or age-related musculo-skeletal changes affect 7% of elderly above the age of 70 years, and the rate of deterioration increases with time, affecting over 20% of the elderly by the age of 80.
    • Osteoarthritis (joint disease occurring due to breakdown of joint cartilage and underlying bone) and Osteoporosis (bones become soft and porous)
    • Wearing dentures because of loss of teeth
  2. Sensory issues:
  • Vision:
      • Lens becomes thick, tends to harden and is more sensitive to glare
      • Pupil becomes smaller letting less light to enter
      • Muscles controlling the opening and closing of eyelids respond slower making it harder to perceive quick moving objects
  • Hearing: Hearing impairment due to poor conduction of sound waves through the ear canal and nerve loss
  • Touch: As skin becomes thinner and loses nerve cells, it is more difficult to distinguish the changes in temperature.
  • Taste and smell:
    • Decreased taste buds and papillae on tongue. A 30 year old person has about 245 taste buds which decreases at the age of 50 and will lose about 65% during the age of 80.
    • Decrease in taste and olfactory nerve ending.
  • Decrease in salivary secretion causes feeling of dry mouth
  1. Renal physiology:
    • Glomerular filtration rate (GFR) decreases to 30-46% along with decreased tubular function
    • Renal plasma flow decreases to 50%
    • Changes in fluid and acid base balance with urinary inconsistency (the loss of bladder control)
    • Reduced ability to respond salt load.
  2. Gastrointestinal physiology:
    • The absorption power of Gastro-Intestinal (GI)cells decreases
    • GI motility decreases with decreased sphincter activity
    • Reduced gastric acid secretion and GI blood flow decreases
    • Gall bladder becomes sluggish in releasing bile
    • Activity of drug metabolizing enzymes reduces
    • Decreased calcium absorption
    • Reduction in the secretion of lactase
    • Constipation
    • Active transport decreases
    • Increased proximal small bowel pH and bacterial overgrowth in bowel
  1. Respiratory and Cardiovascular changes:
    • Sufficient blood cannot be supplied to the body organs as heart doesn’t pump effectively.
    • The blood vessels and some cardiac structures lose their elasticity
    • Accumulation of sclerotic plaques along the wall of the blood vessels causes hypertension and occlusion of blood vessels.
    • Fibrotic changes in the lung tissues reduce the ability of lungs to expand.
    • The combination of reduced blood supply and expansion of lungs causes less efficient respiration. Therefore, the breathing pattern becomes more rapid and shallow.
  2. Changes in endocrine system:
    • Hormone production decreases rapidly with age.
    • Body metabolism is slowed down which causes decreased production of thyroid hormone
    • Chronic diseases like Diabetes Mellitus are common due to disturbance in the production of insulin by pancreas.
  3. Ageing and obesity:
    • Most elderly people belonging to the middle and high socio-economic groups are prone to obesity and complications related to obesity, due to sedentary lifestyles and a reduced physical mobility
    • Obesity is considered as one of the major risk factors which causes the onset and increases the severity of non-communicable diseases
    • In elderly people, obesity contributes to the early onset of chronic morbidities and functional impairments which lead to premature mortality
  4. Cognitive changes:
    • Most elderly people seem to be most vulnerable to psychological dysfunction when they experience change.
    • Changes in cognitive function (referring to memory, learning, and intelligence) and affective function (referring to mood and emotions such as happiness, sadness, fear, pain, anger, and confusion) affect the person’s self-esteem.
    • With time, the person will have difficulty in thinking, remembering and communicating. However, not all people demonstrate these symptoms.

Ageing, its causes and effects on our body