Now, let's get something straight before we go any further. Cortisol is not some evil hormone that's sole job is to make you fat and sick, as many late night infomercials would have you believe. It is a necessary part of your physiology and you would be dead without it. It is part of the flight, fight or fright response which helps you deal with immediate stressors and life-threatening situations. Even when you're not stressed it plays important roles in vigilance and attention. Controlling cortisol levels with drugs is requires much caution.

Problems with cortisol occur when you stay stressed for long periods of time. The cortisol system is designed to turn on to help deal with stress and then turn off again when the stressor is passed. This can be psychological stress, like work, or physical stress, like a tiger attack. If you are constantly stressed and don't turn it off, this can lead to problems with your immune system, weight regulation and, yes, brain function. Too much cortisol for too long can impair learning and memory.

OK, so cortisol is good if kept in check, but bad if it gets out of control.

So let's get back to the title of this article. There is a lot of research in the psychology world showing that unhappy couples in negative relationships activate their stress systems much more frequently, which can eventually lead to poor health. This is probably fairly obvious. Arguments are stressful and we usually dwell on them for too long. Perhaps less obvious is that people in negative relationships are more prone to get stressed in other environment. Laboratory test show that people in negative relationships have an increased stress response to a social conflicts with anyone, not just their ball and chain.

The flipside of this was addressed in a new study published in October 2008 in Psychosomatic Medicine. Researchers looked at cortisol levels in middle age couples with young families to see if the quality of their intimate relationships affected their stress responses throughout the day. Previous studies show that good romantic relationships associate with longevity. Happy married couples, on average, live longer than unhappy couple or singles. In the new study, researchers wanted to know whether or not people in intimate relationships have lower cortisol and are less responsive to stressors from work.

Researchers equipped 51 couples with pocket computers that prompted them to answer some questions about what they had been doing to assess their exposure to stress and measure their levels of intimacy. They were also prompted to take saliva samples every three hours (except when sleeping) to test the level of cortisol, a measure of the level of activity of their stress system. This went on for six days in a row to ensure a good sampling. This is important because it's the first study to get good measurements in everyday life, outside of the laboratory setting.

In the end, couples with higher levels of intimacy had lower cortisol throughout the day and decreased cortisol responses to stressful situations when they arose. In other words, people in positive relationships dealt much better with stress at the office (as measured by their hormonal response to stress) than those that had lower levels of intimacy in their home relationships. This provides another good reason to focus on balance in life. If you want to perform best at work, well, you know what you need to do at home . . .

Reference: Psychosomatic Medicine (2008) 70:883-889.

Copyright (c) 2008 BrainFit For Life