Definition Ageing is the process of growing older over time, and includes changes in both biology and psychology. Biology refers to the way the body functions in an environment, and psychology describes how the mind functions. How people age has to do with genetics, environment, and lifestyle over the lifetime.
What is the information for this topic? Experts do not really know why the body ages as a person gets older. The average life span in 1900 was 47 years. Nowadays, life expectancy is age 76. This increase is due to improvements in sanitation, medical care, and the discovery of antibiotics. Each day in the US, 5,000 people reach age 65, and only 3,600 people die at that age. This increase in the number of older people is changing the makeup of society.
The ageing process is:
genetic, which means it influenced by the factors and conditions that are passed on from parents to offspring
biochemical, referring to activities in the cells, tissues, and organs of the body
physiological, referring to how the body and all its components function together
There are two major theories on ageing. People who follow the program theory think that ageing is based on a biological timetable. Others who believe in the damage or error theory say that ageing occurs as the environment assaults the body and causes it to age. Many people believe it is a combination of biology and environment that causes ageing. Here are the major beliefs for each theory:
The beliefs of the program theory are:
Genes switch on and off sequentially, causing different things to happen at different times. Organ systems in each person can age at different rates.
Hormones act as a biological clock controlling the pace of ageing.
The immune system breaks down, eventually leaving a person more and more vulnerable to infection and disease.
The beliefs of the damage or error theory are:
Cells and tissues have vital parts that wear out.
If a person has a high metabolic rate, his or her life span will be shorter.
Proteins in the body accumulate. This slows down the body's processes and the body begins to age.
Oxygen radicals accumulate in the body and damage it. The organs eventually stop working.
The mechanism in the body that synthesizes proteins ceases to work well. Faulty proteins are developed and cause damage to cells, tissues, and organs.
Genes mutate as the body ages, causing cells to malfunction and deteriorate.
Experts used to believe that chronic disease and disability always accompanied ageing. Now it is known that much disease can be prevented or controlled. A person's lifestyle can help prevent or lessen the effect of many causes of disease. The three leading causes of death among Australians are heart disease, stroke, and cancer. The medical community understands a great deal about how to prevent death from these causes. While a person's genetic makeup cannot be changed, there are things that everyone can do to improve his or her environment and lifestyle, such as:
Stay active. Without exercise, muscle mass declines about 23% between the ages of 30 and 70. Exercise can prevent muscle mass decline.
Maintain a healthy weight. Someone who is as little as 5 kilograms over the average weight for people of the same height and build has an increased risk of disease. Kilojoule restriction may work by preserving cells, moderating a decline in growth hormone, and keeping the immune system functioning well.
Keep interacting with others. People who are married or who have healthy, supportive relationships with others live longer.
Eat 5 servings of fruits and vegetables each day, following the Australian Guide To Healthy Eating. These foods have naturally occurring antioxidants that prevent free radicals from damaging cells in the body.
Avoid getting too much sun.
Keep fat in the diet under 30% of total kilojoules, and get the nutrients needed for a healthful diet.
Have routine physical examinations as recommended by the doctor.
Limit stress or practice stress reduction techniques.
These specific practices have been linked with both the prevention of diseases and the quality of life a person has as he or she ages.
Author: Terry Mason, MPH Reviewer: HealthAnswers Australia Medical Review Panel Editor: Dr David Taylor, Chief Medical Officer HealthAnswers Australia Last Updated: 1/10/2001 Contributors Potential conflict of interest information for reviewers available on request
