Effects of Chronic Stress on DNA
The American lifestyle is rife with stress, with things like caring for the sick and the elderly, heavy job pressures, hectic lifestyles and financial difficulties being a part of our everyday lives.
A survey done by the American Psychological Association (the Stress in America Survey), approximately 42 percent of Americans indicate that their level of stress has risen in the past 5 years. Stress is being reported in teenagers, who often experience more stress than adults do.
Recent research out of the University of California, San Francisco, has indicated that chronic stress occurs even in fetuses and before conception and is programmed into our cells from the moment of conception.
Many studies have indicated that stress is related to DNA damage through the shortening of telomeres, which are the end fragments of our chromosomes. As the telomeres shorten, the cell becomes closer to programmed cell death and this can lead to aging of the cells, increasing the chances of getting a heart attack, cancer, and type 2 diabetics.
Telomeres and their Relationship to Disease and Aging
Telomeres are the end fragments of each strand of DNA in our cells. Every time a cell in the body divides, a little bit of the telomeres, which are just parts of the DNA, gets lost. There is an enzyme known as telomerase that can bring back the levels of telomeres on DNA, but things like chronic stress and the body’s exposure to the stress hormone, cortisol often decrease the amount of telomerase in the body and this causes cellular death or an increase in inflammation of the cells. This causes premature cellular aging and leads to disease.
Stress and Telomere Length
The two major factors in the aging process are genetics and aging; however, stress has become a real possibility in what causes the shortage of telomeres on the aging of cells. The type of stress you are under greatly affects the way stress affects cellular aging.
It appears that many exposures to early life difficulties, such as child abuse and neglect, have the greatest effects on cellular aging as the cells begin to lose telomeres at an earlier age.
These types of stressors allow for persistent mechanisms of cellular telomere shortening that affects the telomere length throughout a person’s life. They may also cause factors to come into play that keep the telomere length shorter throughout a person’s life.
Other types of stressors, including the typical job stressors, financial stressors and the stressors of being a caregiver later on in life also have an effect on the shortening of the telomere length. In fact, this relationship between cellular aging and stress occurs throughout our lives and is vital to the way we are made.
The brain is always looking out for real or perceived threats to our survival. When we are exposed to many years of chronic stress, this overrides the normal aging process, making it appear that the telomeres are from a much older person than our chronological age should suggest. People suffering from various psychiatric problems, particularly depression, have shorter telomeres and are therefore at an increased risk of an earlier death due to DNA damage.
When do the effects of stress begin?
As mentioned, the effects of stress begin prior to the moment of our conception. The fetus’ environment in the uterus is a result of the mother’s preexisting psychological and physical health.
Several studies have looked at the mother’s health and telomere shortening in their children. They have shown, for example, that anxiety in pregnancy shortens the telomere length in their infants. This means that, because of the DNA we are born with, we are at an increased risk of premature death from a very early age.