CAUSES OF AGING

Factors in Aging

Aging is caused by a combination of factors:

• Levels of Toxins in the body
• Cell Nutrition
• Physical Activity
• Emotional State
• Genetic Influences
• Environmental Factors
• Behavioural Factors

Theories of Aging

How we age has support of two main theories:

1. Genetic Theory [Stochastic Theory] - proposes that aging results from genetically programmed changes regulated by the immune system and thymus gland. The thymus gland rapidly withers after adolescence to 10-20% of its size at birth by the time a person is 45 years old. By the time people are 60, thymic hormones can no longer be detected in the blood.
2. Free Radical Theory - proposes that aging results from changes in the information that is provided by the cell nucleus during normal cell function. An accumulation of genetic errors due to environmental damage in turn results in changes in DNA (deoxyribonucleic acid--the molecule that carries the genetic code of a cell), resulting in cell mutations and malfunctioning. Cancer cells are a typical example.

We cannot do much about our inborn genetics, other than be aware of any weaknesses we may have inherited and mitigate them as much as possible, but we can certainly take influence environmental factors.

Secondary theories that have spurned from the above include:

• Caloric Restriction Theory - related to the Free Radical Theory. The lowest morality rates are in those with a body mass index (BMI) in the range of 21 to 22.
• The Hormonal Theory - replacement of these hormones may prevent the aging process. Among the hormones under study are: DHEA, melatonin, testosterone, and estrogen. Currently insufficient evidence to support this theory, but that does not invalidate it.
• Personal Attributes Theory – a Boston study demonstrated that certain personal attributes were common to those who survived longer than average. These include low levels of depression, obesity, excess alcohol, and smoking coupled with high levels of stress coping ability, use of humour, intellectual stimulation and social interaction and support
  

Internal Aging Forces

• Genetic programming
• Protein damage and decreased protein turnover
• Neuro-hormonal disregulation
• Glycation
• Mitochondrial damage
• Damage to lipid fats
• Oxidative stress
• DNA damage and faulty DNA repair. Alterations in gene expression

External Forces

• Social adaptive lifestyles – developing the wrong habits such as smoking, poor eating habits, drug usage.
• Environmental - toxins, stressful living or working environments
• Income restraints on capability to provide sufficient nutrition

Normal Cell Function and Free Radicals

As part of normal metabolism, human cells produce chemically reactive substances called free radicals.

Free radicals are highly toxic and can damage delicate cellular elements, such as membrane fats and genetic materials. It is held that these free radicals are responsible for a number of age-related illnesses and diseases, including cancer and arthritis. However, the damage produced by free radicals is so widespread that it suggests there are some yet undefined intermediates that may cause specific damage to genes and to DNA. So, although compelling evidence suggests that aging is genetically determined, no one yet knows for sure how this happens. However, environmental factors seem to accelerate the process.

The Influence of Genetics on Aging

Even in the best of environmental conditions, various species of animals and plants mature, grow old, and die at widely differing rates. Identical twins show much more closely correlated longevity than fraternal twins, and females outlive males.

Environmental Factors That Modify Aging

Genetic influences may have more impact than environmental factors, but the environment determines the aging experience. Improvements in nutrition and sanitation and the decrease of infectious diseases such as tuberculosis, gastroenteritis, typhoid fever, and cholera have played a significant role.

A person's lifestyle is an important factor in how we age. Not smoking, moderation in alcohol intake, adequate exercise and rest, a diet high in fibre content, effectively handling stress, and a positive outlook have all been suggested as a means to better health and longevity.

Principle Attributes that Accelerate Aging

In summary, all these theories combined allow us to conclude some important antiaging principles:

• Manage the mind:body connection
• Avoid toxins which overtax the body, and divert the body’s processes from normal functions to detoxification functions
• Nourish cells to ensure healthy operation and replication
• Reduce cellular damage, thereby preventing prevent diseases
• Avoid life threatening build up of fat around essential body organs
• Avoid aging caused by diuse
• Reverse signs of aging through boosting the bodies own processes or by cosmetic intervention.
  

To find out how to incorporate these principles into your life, read more on antiaging methods.

Next: How Cancer Causes Aging

Aging Causes Index | Why Skin Ages | Behaviour | Free Radicals | Exercise | Smoking | Cancer