"Stressed out" is a phrase commonly applied to people who are tired and anxious. The effects of prolonged stress are widely perceived to impede both health and life span. A recent and refreshingly readable study confirms the link between mental stress and aging. It also reveals that how one perceives and deals with mental stress is a major determinant of how that stress affects the body. The results of the study, published in the Proceedings of the National Academy of Sciences, are available at Proceedings of the National Academy of Sciences (PNAS). This Research Update column highlights articles related to recent scientific inquiry into the process of human aging. It is not intended to promote any specific ingredient, regimen, or use and should not be construed as evidence of the safety, effectiveness, or intended uses of the Juvenon product. The Juvenon label should be consulted for intended uses and appropriate directions for use of the product.

By Benjamin V. Treadwell, Ph.D.

What we’re learning about psychological stress reminds me of what happened with cigarettes. Virtually everyone knew smoking was probably bad for us, but some of us continued with this addiction, taking refuge in the lack of strong experimental evidence to prove the negative effects. Now, clear evidence is available, and it shows how the toxic oxidants in cigarette smoke damage cells.

Similarly, we know intuitively that psychological or mental stress can't be healthy, but once again many of us require hard experimental evidence before changing our lifestyle to correct this potential problem. The information obtained from a recent study on the unhealthy effects of this form of stress may help make you a believer in just how dangerous mental stress appears to be for our health and longevity.

People under continuous mental stress tend to have a higher frequency of diseases including the common cold, heart disease and early dementia. Psychological stress can also produce cellular senescence. Although there appears to be an association between mental stress and disease, a question remains as to the biological cause(s) of this form of disease.

A recent study has demonstrated for the first time a dramatic association between psychological stress and physical markers of cellular stress and aging. To put the study in context, I want to briefly summarize the telomere theory of aging. This theory posits that the telomere, a specialized DNA protective structure at the ends of our chromosomes, determines when a cell is to die. With each cell division, the telomere is shortened by a fixed amount. In fact chromosomes examined from older animals, including man, have shortened telomere lengths relative to those examined from younger individuals. Once the telomere is whittled down to a critical length, the cell can no longer divide. The net result is cellular senescence and death.

The recent study demonstrated the deleterious effects of mental stress on the length of telomeres in humans. The study suggests we can accelerate our biological age by as many as 17 years by being exposed to what we perceive to be a high psychological stress for prolonged periods of time.

The objective of the study was to determine if psychological stress has a real effect on the production of tissue-damaging oxidants. The investigators hypothesized that psychological stress may increase the production of toxic oxidants that attack the telomeres. In addition, they wanted to examine whether this stress had a negative effect on the activity of the enzyme telomerase that protects telomeres.

The experiment involved testing two groups of otherwise healthy women of similar age and weight. Half of the women were caring for a chronically-ill child (the caregiver group) and thus were considered to be under high psychological stress. This form of stress is referred to as objective stress, since it was identified by the investigators’ objective assessment, not the subject’s perception. The other half (the control group) had normal healthy children and otherwise similar life-styles. They were considered to have low objective stress. The women in both groups were asked to take a standard test designed to measure how they rated the level of stress they encountered on a typical day. This form of stress is referred to as perceived stress.

As the researchers anticipated, the caregivers had significantly shorter telomeres. Furthermore, those with the shortest telomeres also had lower serum levels of the antioxidant vitamin E, and higher levels of a cellular metabolite known as isoprostane, which is an indicator of increased cellular levels of toxic oxidants. In other words, psychological stress increased oxidative stress, which destroys tissues and may be at least partly responsible for the decreased length of the telomeres.

The intensity or degree of these effects varied from person to person within the caregiver and control groups. Scientists were intrigued to see that some in the caregiver group had only a small increase in these stress markers, while some in the control group had a high level of these markers. Two explanations emerged: the length of time the mother was taking care of the ill child, and the individual's perception of the amount of stress she was experiencing. Those who perceived their situation as high stress (whether or not they experienced objectively determined high stress) had higher levels of the markers of oxidant stress than those who perceived it as low stress. In other words, the negative biological effect appears to be determined by how you perceive stress, not by whether someone else thinks you are under stress.

A second major conclusion was that the duration of a stress-producing activity has a significant effect on the amount of damage incurred. Small amounts of stress and stress of short duration appear to do little cellular damage. In fact, some speculate that experience in handling moderate stress may help immunize the individual against damage from future bouts with stress. However, an overwhelming amount of stress, or stress for long durations, can do significant damage.

The key to avoiding this damage is to avoid excess stress, if possible, or learn to deal with it. As this study demonstrates, a situation is damaging to the body only if it is perceived as stressful. Numerous methods available today can help attenuate the damaging effects of mental stress. These include proper nutrition, sufficient sleep, exercise, and various controlled mental activities, such as meditation, to help channel stress into discrete, more manageable mental compartments. In other words, don't try to solve the entire stress package as a whole, but instead disassemble it into distinct parts and deal with them one at a time. Just as smoking can be conquered with commitment and effort, so can psychological stress.