Don't Cross Your Eyes...They'll Get Stuck That Way!: And 75 Other Health Myths Debunked (21 page)

A comprehensive review looked at all the studies evaluating whether heated, humidified air helps with the common cold. In these studies, the heated steam is delivered to your nose through some sort of machine, whether through a mask (this seems to be popular in Britain) or through a vaporizer with a nozzle (the choice of most Americans). Since we should always ask ourselves what they did to convince a comparison group that they were getting the same treatment, you will be happy to know that the comparison groups in these studies usually received unheated humidified air.

Studies of hot steam for cold treatment from Israel and Britain did show some benefit for using hot steam in people with colds. People in these studies who received hot steam reported fewer cold symptoms in general, although no specific help was found for symptoms like cough or nasal congestion. However, three very good studies, all randomized controlled studies done in the United States, did not find any improvement in cold symptoms for people using hot steam. Neither their symptom scores, nor the cultures from their nose to see how many viruses were sticking around, were any better for those who used hot steam. Moreover, people using the steam did not think that it had helped.

These studies give a mixed picture as to whether hot steam will help your cold. With multiple good studies showing no difference and the overall mixed results, the experts conclude that hot steam is not recommended for treating cold symptoms.

Stress

Stress will make you sick

Stress works in the body in some interesting ways. When your body is under stress, it produces more of a hormone called cortisol that helps you think fast and brings more energy to your muscles, while slowing down the systems you do not need as much in the short term (such as your immune system or your digestive system). This is a great response in the short term. If you are running away from an animal that is about to attack you or you are rushing to beat a deadline, that stress response will give you the energy and focus you need. Stress can actually help you be more productive and manage challenges.

The problem for your body seems to come in when you are under stress for a long period of time. One example of a person under stress for a long time would be a parent taking care of a child with a chronic disease. Studies suggest that the white blood cells, the key cells of the body’s immune system, seem to age more rapidly in parents of chronically ill children. People who are under stress for a long period do not make quite as much of a chemical called telomerase that helps to extend the life of your body’s hardworking cells, and so their cells age more quickly. Depression works in the same way; people who are depressed for a long period of time also make less of this chemical that works to preserve the immune system’s cells.

Whether it is because of the effect on these immune cells or by some other mechanism, stress seems to leave a person more susceptible to getting sick by germs to which they are exposed. A number of studies test this idea of stress making you sick by putting cold viruses directly into volunteers’ noses and seeing who gets sick and who stays well. In a small study with seventeen subjects, their perceived stress and their overall mood were not connected to whether they got a cold; however, people who had had more major life events in the previous year were more likely to get colds. These included events that might be stressful, such as moving, graduating, marrying, or having someone close to them die. In a larger study of 394 volunteers, those with more psychological stress were more likely to get infected with the cold viruses put in their noses.

Stress might contribute to other kinds of sickness as well. There is some evidence that stress might make heart disease or headaches worse, even though stress does not cause a heart attack or headache or depression the way that a virus causes a cold. Chronic job stress can increase a person’s overall risk of heart attacks by up to 50 percent, but the effect of stress varies from person to person. Depending on your genetics or on your perception of how much control you have in a particular situation, you might be less affected by stress. Some headaches, particularly tension headaches, are increased by stress, because some people increase muscle tension in their neck and shoulders when they are stressed. Stress has also been linked to slower healing of wounds and with flaring-up skin conditions such as herpes or acne (although it is sometimes difficult to tell which comes first—the acne or the stress). On the other hand, there is no evidence that stress causes cancer, diabetes, or many other diseases.

Stress is a complicated thing. How you handle it, what your underlying genetics are, and what other health problems you might have or be exposed to will alter how stress impacts your body and whether it will make you susceptible to various diseases.

Stress will give you high blood pressure

Stressful situations can raise your blood pressure temporarily. An increase in blood pressure is one of the ways your body responds to challenging situations that demand a flight-or-fight response. Much to our surprise, there is no evidence that stress causes high blood pressure over the long term. The evidence actually suggests that people with higher levels of stress do not have higher blood pressure overall. And there is no evidence that having lots of short-term spikes in your blood pressure raises your blood pressure over the long run.

While a few small studies that looked only at a few hundred people found connections between anxiety scores and long-term high blood pressure, other factors such as age, having parents with high blood pressure, or being obese were much more strongly tied to high blood pressure. While these studies already suggested that stress was not the most important issue in developing high blood pressure, their results were blown away by a huge study that suggested that stress levels might not play any role in developing high blood pressure over time. In a big study of 36,530 men and women who were followed for eleven years, they found no connection whatsoever between psychological stress scores for anxiety and depression and the development of high blood pressure. In fact, when they started this study, the people with higher levels of anxiety or depression symptoms actually had lower blood pressures than the people who had less psychological stress. As the eleven years of follow-up went on, the people who had increasing levels of anxiety and depression over time were even less likely to develop high blood pressure. This is the opposite of what you would expect. Instead of having more high blood pressure develop in the people who had increasing psychological distress, they actually had more cases of low blood pressure. These effects were not explained by the use of medicines for depression or high blood pressure, nor were they explained by differences in age, gender, baseline blood pressure, or other risk factors for developing high blood pressure.

Your family’s genetics, how much fat you have around your middle, and other conditions like diabetes and high cholesterol are connected with the development of high blood pressure over the long term. People who are under stress may also do things that are less healthy for their hearts and for their blood pressure. Eating too much, drinking more alcohol, using recreational drugs, and not sleeping enough are all unhealthy behaviors that people do when they are feeling stressed. Even if stress itself is not causing long-term high blood pressure, these behaviors could put you at risk of not having a healthy heart or healthy blood pressure.

Just because stress is not the primary cause of high blood pressure, it does not mean that people with high blood pressure could not benefit from reducing their stress. If you suffer from high blood pressure, you should consider whether you do some of the unhealthy things just listed when you are under stress and whether you could eliminate or reduce them. Furthermore, certain behaviors that reduce your stress can also reduce your high blood pressure temporarily. Programs that teach meditation, progressive muscle relaxation, and other stress management programs have been shown to result in better blood pressure for some people struggling with high blood pressure.

Stress can give you a heart attack

As we have mentioned, your heart and other parts of your body respond to stressful situations in certain ways. A situation that causes anxiety, like having to speak in public or finding out very bad news, does make the beating of your heart speed up and make your blood pressure rise. Many people believe that stress of various kinds triggers heart attacks. For example, some people report that they think having a stressful job will lead to more heart attacks by increasing their blood pressure. Others believe that immediate stressful events, like hearing very shocking news, will trigger heart attacks directly. In a study of patients who had suffered from a heart attack, 15 to 30 percent of those who were admitted to a hospital had had a recent, severe emotionally stressful occurrence. While this points to a link between a heart attack and emotional stress, it is also possible that heart attack victims report more stressful events because they remember them clearly and assume that they are connected to their heart attacks. (This is that problem called recall bias again.)

So the bottom line is that stress can give you a heart attack—but it is important to realize that this is usually only a concern for people who already have a diseased heart. Stressful situations can reduce the amount of blood flowing to your heart as part of your body’s short-term response to stress. If you already have partially blocked heart blood vessels or bad heart disease, it is possible that when a stressful situation increases your heart rate, increases your blood pressure, and causes less blood to flow to your heart, it could be enough to trigger a heart attack. This is not the cause of most heart attacks, but it is possible that this could happen. Again, having a heart attack during a stressful event requires that you have some sort of underlying problem with the blood vessels around your heart or problem in how your heart works. The diseases that affect the blood vessels around your heart and the heart itself are most often caused or made worse by having a high fat diet, not exercising, and smoking. Changing or avoiding these behaviors will go much further in preventing you from having a heart attack than trying to avoid any task or interaction that might cause you some stress.

Contrary to what many of us would expect, having short-term stressful reactions again and again is not clearly linked to developing heart disease over the long term. Scientists have found some evidence that both immediate stresses and having stress over a long time can lead to changes in how your immune system and your heart interact, and this can put you at more risk of having heart disease. Some studies also suggest that experiencing stress over time is tied to higher cholesterol and a greater chance of having a clogged artery. Once again, this might be because you react to stress by eating unhealthy things or not exercising—not because of the stress itself. But having high cholesterol and clogged arteries, along with other behaviors that are bad for your heart like smoking, puts you at much higher risk for heart disease and heart attacks. Other studies suggest that it is really not having enough rest and recovery time for your body, instead of the absolute level of stress, that puts you at increased risk for heart disease and heart attacks over the long term.

There clearly are ways in which excess stress could have a negative effect on your heart. The biggest lesson you should take from this is that there are important ways you can manage your stress and protect your heart at the same time. You can never avoid stress altogether. Exercising, eating a diet that is higher in fruits and vegetables and lower in fats, and quitting smoking are probably the very best things you can do for your heart in the long term. Exercising, in particular, will keep your heart healthy and will help you have less stress at the same time.

Stretching

You should stretch before you exercise

Almost anyone who works out, plays sports, runs, or engages in regular exercise will tell you that you should absolutely stretch first. Stretching is supposed to help you perform better. Even more importantly, stretching is supposed to prevent injuries. The idea of not stretching before a run or before a game is anathema to most athletes. Entire books are devoted to describing the best ways to stretch, and careers of coaches and trainers have been built upon their knowledge of proper stretching. How could we even suggest something so dangerous as not stretching before exercise?

As much as it may shock you, there is good scientific evidence that stretching does not reduce your chance of being injured during sports or exercise. Several meta-analyses or comprehensive reviews have been done to compile all of the studies on this subject. In a 2004 systematic review by scientists at the Centers for Disease Control, the authors reviewed 361 studies and identified six that most rigorously tested whether stretching reduced the chance of getting injured. Most of these studies tested the effects of stretching for people going through basic training in the military or for high school and college football players. The combined verdict from these studies was that the enhanced flexibility created through stretching did not reduce the injuries seen in sporting or fitness activities. So even if you stretched carefully, you were still just as likely to get a pulled muscle as a person who did not stretch first.

Even if stretching will not help you prevent injuries, you still may cling to your stretching routine because you think it prevents your muscles from getting sore. In particular, many people stretch before or after exercise or at both times in order to prevent their muscles from being sore the day after they exercise. Another excellent systematic review compiled the results of ten randomized trials that looked at the effect of stretching before or after physical activity on muscle soreness. These were not great studies—they were small and of questionable quality—but they do give us some idea of what stretching does for muscle soreness. And the answer is: very little! Stretching had very little to no effect whatsoever on muscle soreness in half a day to three days after the physical activity.