Ageing Directly
Influenced by Obesity, Smoking
Jun 14, 2005
According to the researchers, Obesity and smoking speed
up ageing by shortening the caps that keep chromosomes
from fraying.
People who smoke cigarettes or are obese have shorter
telomeres - the caps on chromosomes - which make them
biologically older than their non-smoking, leaner counterparts.
Each time a cell divides, telomeres get shortened.
The loss is linked to ageing, which is why telomeres
are believed to hold the secrets of youth and the ageing
process.
As telomeres get smaller, the chromosomes can become
unstable and increase the risk of mutation.
The researchers inform, "Obesity and cigarettes
cause oxidative stress, leading to the loss of these
telomeres - a marker of accelerative ageing - which
accounts for the rise in heart disease, diabetes, osteoarthritis
and other age-related disease."
Oxidative stress is damage to cells and DNA caused
by free radicals - the charged particles found in the
environment and produced by processes in the body.
The Telomere length from blood samples of 1,122 British
women between the ages of 18 and 76 were compared. Nearly
120 of them were obese, 531 had never smoked, 203 were
smokers and 369 had quit.
It was observed that a decrease in telomere length
was directly associated to the obesity level of women
and the number of cigarettes they had smoked.
Obesity
affects about 300 million people worldwide and is a
host of health problems such as diabetes, heart disease,
stroke and other illnesses.
Smoking
is a leading cause of lung cancer and COPD (Chronic
Obstructive Pulmonary Disease), which includes emphysema
and chronic bronchitis.
Source: http://www.abc.net.au
|
