Monthly Archives: September 2009

Is STRESS getting a bad rap?

Stress research is a huge and growing field of science. Stress can trigger and exacerbate many types if physical (heart disease, diabetes, asthma, obesity, etc) and mental disorders (anxiety, depression, etc). Stress has also been shown to negatively impact the immune system on a cellular level. It’s no wonder we hear so much about how stress is bad.

But, what most reports fail to highlight is that we only really need to worry about chronic stress. Chronic stress, as mentioned in the pre-requisite entry, is more dangerous because of the long-term health effects posed by an elongated stress response. So, why is stress getting a bad rap (or why do I think so)? Two reasons: 1. Failure to differentiate between chronic stress and acute stress/normal stress. 2. Failure to recognize that some (acute) stress is good for you! That’s right, I said it. Some stress is good for you! Let’s take an example that everyone can relate to: TAXES!

Most people would agree that doing taxes is stressful. I concur. But let’s break down the experience. Tax time comes around, and you start to feel the tension, the worry, the pressure. Why do you feel those things? It could be a number of things, but most likely you have that reaction because doing taxes is unpleasant, and could cost you time and money. The idea of taxes is also unpleasant because it’s something we must do. If we don’t there are potentially major repercussions (i.e. audit, jail time). Taxes also have potential to affects our financial security and even potentially affect our home life and relationships. The actual tasks associated with taxes are also unpleasant; the forms and language are confusing, the mathematical calculations, etc. Essentially everyone finds these experiences unpleasant. The big questions are “How do you deal with the unpleasantness? How do you cope?” Some people suck it up, gather the appropriate forms, envelopes, stamps, software, whatever is needed, put aside some time, and file their taxes, on time. Other people avoid filing their taxes, either through procrastination, or by failing to file entirely.

If you avoid your taxes (or dealing with any stressor), you are setting yourself up to experience stress over a longer period of time, whether you put it off until the last minute, or you don’t do them at all, in either case you are going to worry about your taxes more and for a longer period of time, thus welcoming and contributing to chronic stress in your life. Not good.

If you approach your taxes, engage the process, and take the steps necessary to complete the task, then you will successfully remove the stressor, sooner rather than later. Good for you!

So what’s the real difference in these two reactions? Everyone experiences some initial stress associated with doing taxes, but some people, over the long-term experience less stress associated with taxes (or with their job, relationship, bills, whatever). The major difference is that individuals who engage the process of doing these taxes used the initial feelings of stress to inform and guide their behaviors. Individuals who avoided doing their taxes did not gain anything from the experience of stress.

Stress is part of our physiology (and psychology) for good reasons. Stress can be very informative. It tells us when something is wrong, when we are in danger, or something in our life needs attention. Stress acts like a signal system that tells us to take action (whether it be run from the hungry lion, or deal with our taxes, or whatever the source of stress may be). Acute stress is not something to be avoided, it is meant help us recognize how and when there opportunities to reduce long-term experiences of stress. Problems arise when we ignore and avoid responding to our stress, or do so lackadaisically, or irrationally.

Let’s go back to the question at hand: Is stress getting a bad rap?

Yes, I think so. Current societal trendsĀ encourage eliminating all stress from our lives. Instead of eliminating or avoiding all stress, we should engage it. We should be listening to the stress our lives. Use it to inform our decisions, guide our actions, help us prioritize and be a source of motivation. As it stands, based on our current conceptualization of stress, I suggest that we are missing an opportunity to live more productive and efficient lives and live with less chronic stress.

*The ideas from this post stem from various pre-existing theories of stress, namely Social Problem Solving Theory (see D’Zurilla & Goldfreid, 1971; D’Zurilla & Nezu, 1982). Social Problem Solving (SPS) Theory is part of my current asthma research and will be discussed in more detail in its own entry. Stay tuned!


WHAT IS STRESS? A pre-requisite entry for “Is stress getting a bad rap?”

Stress is a major buzz word in today’s society. That’s not likely to change anytime soon. Talk of stress permeates daily news articles, talk shows and websites (like this one!). You can create a RSS feed about stress, and there are articles about reducing the stress associated with using RSS feeds!

Why has stress become such a hot topic, for both the lay person and the research community? Well, stress affects everyone! And, it is associated with a wide variety of health issues. Besides the more well known diseases, like heart disease and diabetes, you can find articles about stress contributing to practically any disease or condition. Here’s a bit on stress causing hair loss. Here’s one on stress causing ADHD. So we get it, stress is bad for your health.

But hang on a minute! Hold your horses!
Hold your horses!

Stress has many definitions (engineering, health, economic, etc). One must be very clear, especially in research, about what definition of “stress” you are using. Stress, in terms of health, is the psychological and physical response to our perceptions of our circumstances being threatening or overwhelming. The things in our life that elicit the stress response are called “stressors”. So, just to be clear, stressors are the cause and stress is the response.

Stress, as a response, originally evolved as an adaptive mechanism. When animals (and humans) are presented with a threat to well-being, (example, a hungry lion chasing you) the stress response, characterized by increased cortisol, heart rate, respiration, adrenaline, etc, helps you escape the threat of the lion! Our perception of the lion as stressful/threatening and the physiological changes that follow help us survive.

Stressors today are very different from the hungry lion (e.g. worry/anxiety about money troubles, traffic jams everyday after work, relationship troubles, etc). Most contemporary stressors are not threatening our immediate survival, but we still experience stress. Unfortunately, for humans, most of our stressors don’t go away like a lion might. The stressors of contemporary living are longer lasting and there are more of them and as a result we experience a continually activated stress response (chronic stress).

This point is well illustrated by the title of Robert Sapolsky’s book “Why Zebra’s Don’t Get Ulcers”. The idea is that once the lion has stopped chasing the zebra, the stress response shuts off (and the zebra doesn’t get an ulcer).

Both short-term/acute and chronic stress are driven by a hormone called cortisol. Cortisol causes and helps trigger many of changes characteristic of the stress response mentioned above. While those changes are helpful in the short-term, to escape the lion, if continually activated the stress response can have a massively negative impact on the cardiovascular system, immune system, nervous system, digestion, sleep, mood, etc, basically all aspects of health.

Once we understand what stress is, many important questions follow:

1. What are the stressors in our life?
2. Is there something about the way we perceive our world, our situations that makes us experience life as more stressful than it ought to be? Are we causing ourselves stress?
4. How can we reduce the negative impact of stress?
5. Why are some people more negatively affected by stress than others?

I could start to answer these questions, but, instead, I’d like to ask a couple questions that I don’t think are being asked enough: Is stress all that bad? Is stress getting a bad rap? I’ll address those questions in the next post!

Ozone pollution and the immune system

Vehicle Exhaust + VOC + Sunlight=OzoneWith my work at Clean Air Council on air pollution and respiratory health I’ve come across some very interesting research of how the body and immune system are affected by air pollution.

Let’s take ozone for example. Ozone is cheekily described as “good up high, bad nearby”. In other words, ozone in the atmosphere is a good thing because it filters dangerous solar UV radiation, but ozone at ground-level is unfavorable because it is toxic to the body, causing coughing, respiratory inflammation, chest pain, etc, and can contribute to health issues such as asthma and cardiovascular disease.

What I find to be particularly interesting are studies like Devlin et al. (1997) that provide insight into the variety and complexity of the body’s responses to specific pollutants.

First, a little background information. When a toxic substance enters the body our immune system responds with a myriad of cellular and molecular changes (represented by the presence of “markers”) that are meant to neutralize or minimize the threat posed by the substance. These changes can be measured, and thus a substance can be identified as dangerous to the body because it elicits certain biological responses.

Inflammation is one example of an immune system response to a potential threat. Many studies use measurements of cell markers of inflammation in fluid inside the lungs to find out if a substance is toxic. However, inflammation markers are not the only measure of how much of a threat something poses to our bodies. For example, Devlin et al. also measured a marker called lactate dehydrogenase, an enzyme released when cell are injured or die.

Interestingly, some markers (eg. inflammation markers) stopped appearing after extended ozone exposure, in other words their response was attenuated. This suggests that the body stops responding negatively to ozone. So the question remained, “IS OZONE BAD FOR US?”.

But, other markers, namely lactate dehydrogenase did not attenuate, and was found to be present throughout elongated and repeated exposures to ozone. This suggests that ozone does continue to damage the body.

I am no cellular or molecular biologist, so bare with me. But, from what I gather, these variations in response at the cellular and molecular level hint at the complexity of the immune system. Now I am sure others have a better explanation, but for my own sake I would like to offer one possible explanation for the observed differences in inflammation and lactate dehydrogenase response and say that it is partly a function of limited resources and demand. This isn’t supposed to be economics, so let me explain.

The fact that inflammation markers are found to attenuate after repeated exposures suggests to me that the immune system is capable of re-allocating those resources in the face of inescapable adversity. Put another way, the immune system is often talked about as a sense organ and can make “decisions” based on the sensory input. In this example, the immune system detects a threat to the body (ozone) and the body initiates it’s first line immune response, inflammation. Since the exposure to ozone did not abate, and inflammation is an entirely ineffective response to ozone (granted inflammation is great at neutralizing an infection, but inflammation doesn’t do much to stop or protect us from ozone), the immune system “knew” to withdraw/attenuate the inflammation response. In this way the immune system does not employ brut force methods to dealing with toxins, but has the ability to try a certain approach and sensing whether or not it is working, and if not, then it stops using that approach. Very cool!

Not so cool was that the researchers found that the participants cells continued to release lactate dehydrogenase, indicating that the cells were still injured during both acute and long-term exposure to ozone. What this suggests then is that while ozone may not pose a long-term threat to our health via extended periods of inflammation (which can lead to disease such as asthma and cancer), one way or another ozone does continue to injure the cells that make up the lining in our lungs. Thus, ozone needs to be avoided and the levels of it in our environments should be reduced.

I think this sort of research is interesting but also very important for human health in general. We need to continue to investigate how various chemical compounds impact our bodies. A great area of uncertainty stems from the rise of nano technology and molecular manufacturing. There are many unanswered questions about whether or not these synthetic materials that are built on a molecular level will pose health threats, particularly to our respiratory system and immune system. I bet we will see a surge of research in these areas in the coming years.