Meditation Protects You Against Stress and Disease: The Latest Scientific Research

Q. Is it true, Peter, that in the last few years science has taken a big step forward in understanding 1) how psychological stress contributes to disease and 2) how meditation can offset stress and either cure or lessen the impact of disease?

A. Yes to both questions. We’ve known for some time that stress is a major factor in the onset or worsening of many diseases, but we now have solid scientific research identifying the main biological changes triggered by stress and explaining how they undermine the immune system’s function. There is also recent scientific research which shows that meditation is an important safeguard against stress-related diseases and that it can produce effects equal to standard medications.

Q. What are the main biological changes caused by stress?

Cortisol: A natural anti-inflammatory

A. One of the key scientific breakthroughs in the last decade is a better understanding of the role of cortisol, a hormone produced by the adrenal glands. Cortisol is our “stress hormone” and it plays a major part in how the body responds to stress.

Cortisol functions primarily as a natural anti-inflammatory. Because so many diseases are inflammation-based, nature has given us our own internal anti-inflammatory, which is cortisol. Some examples of diseases that have significant inflammation are asthma, pneumonia, rheumatoid arthritis, hepatitis-C, Crohn’s Disease, coronary heart disease, multiple sclerosis and other auto-immune disorders.

What we’re learning, however, is that prolonged stress decreases our body’s sensitivity to the anti-inflammatory effects of cortisol. In response to stress and to protect the body from inflammation (and ultimately disease), the adrenal glands make more cortisol.

However, what the scientific research shows is that when there is prolonged stress, although the body produces more and more cortisol to fight inflammation, even these highly elevated levels of cortisol no longer decrease inflammation. The result is what one scientific researcher describes as “runaway inflammation,” a serious condition which promotes the development and progression of many diseases.

The landmark April 2012 study

Q. Have there been any scientific studies showing exactly how prolonged stress affects cortisol’s ability to control inflammation?

A. Yes. There were studies in 2010 that found a correlation between high cortisol levels and high death rates in patients with acute coronary syndrome – an impending heart attack.

But the first study to show that prolonged stress effectively shuts down cortisol’s ability to control inflammation was published only last year, in April 2012.  Everything I’ve said so far about the new understanding of how elevated cortisol levels affect inflammation is based on the April 2012 study.

Q. Do you consider the April 2012 study a landmark study?

A. Yes. This study may be the “Rosetta Stone” (or key) for helping physicians understand why so many of the diverse diseases that we deal with in medicine are inflammation- based.

For example, if you ask most people and even some physicians what causes coronary artery disease – which is hardening of the arteries in the heart – they would probably say, “too much cholesterol.” However, the most recent studies show that coronary artery disease is an inflammatory disease of the cardiovascular system.

The substance we call “plaque” in the areas of hardening in the arteries consists mostly of scar tissue from the inflammatory process, mixed in with some cholesterol and calcium. Today there are cardiologists who, as part of their standard evaluation of a person at risk for cardiovascular disease, will measure what’s known as an “inflammatory reactive factor” (C-reactive protein) to see if there’s evidence of inflammation. When an inflammatory illness is present, whether cardiovascular disease, pneumonia or some other disease, C-reactive protein will be elevated.

To sum up: what happens with cortisol is very similar to what happens with diabetes. The most common form of diabetes is not caused by a lack of insulin; it’s caused by the body cells becoming insensitive to the higher levels of insulin produced to control blood sugar. Similarly, inflammation is not caused by a lack of cortisol; it’s caused by the body cells becoming insensitive to the higher levels of cortisol produced to control inflammation.

The real culprit of disease

Q. Do you need to see more research before you can form a definite opinion about the correlation between stress, inflammation, and disease?

A. No, I’m convinced the correlation exists and that science has uncovered the real culprit of disease. But the research is very recent and medical doctors are only beginning to understand that it has many implications. However, the new understanding of cortisol’s pivotal role in the disease process enables us to draw a lot of different threads together.

For example, such widely different diseases as fibromyalgia and acute coronary artery syndrome both stem from disorders in the body’s regulation of cortisol. Fibromyalgia, which affects primarily women, is an inflammatory disease caused by inadequate production of cortisol. We’ve already discussed how inflammatory diseases can occur when the body cells become insensitive to the highly elevated levels of cortisol. But we now know that inflammatory diseases can also occur when the body does not produce enough cortisol to control the level of inflammation caused by a disease, as in fibromyalgia.

One of our main therapies for fibromyalgia is sleep maintenance (encouraging 8-9 hours a night) because most of our cortisol production occurs naturally at night during sleep. Without that nightly cortisol surge, we would have low cortisol levels and be at a higher risk for a disease like fibromyalgia.

Meditation strengthens the immune system

Q. What has science learned about meditation‘s ability to offset the disease-producing effects of prolonged stress?

A. A number of studies published in 2011 and 2012 show that meditation can actually reduce the activity of certain immune cell proteins linked directly to increased inflammation. In other words, the research suggests that meditation can reverse the inflammation effects associated with the highly elevated cortisol levels brought about by prolonged stress. This is a truly astounding discovery with broad implications!

Q. Is this the only study showing the effects of meditation on the immune system?

A. No, but it is the first study to show the beneficial effects of meditation on the inflammatory process that we now know causes most diseases.

Q. Can you tell us about the other studies of meditation’s effects on the immune system?

A. Yes. In 2008, there was what I consider also a landmark study though it did not focus on cortisol or inflammation. The research on the relationship of stress to cortisol levels, inflammation and disease is very recent. The 2008 study was done several years before that research was available.

This study involved two groups of people with HIV who were suffering from stress. The HIV virus attacks the cells known as CD4 T lymphocytes (often called CD4 T cells), which coordinate immune system activity when the body comes under attack by infection. The HIV virus slowly eats away at the CD4 T cells, gradually weakening the immune system. Psychological stress can accelerate CD4 T cell decline.

In the 2008 study, one HIV group participated in an 8-week mindfulness meditation stress-reduction program; the other group did not. The group in the meditation stress reduction program showed no loss of CD4 T cells during the 8-week period. The control group, by contrast, showed significant declines in CD4 T cells.

The immune system’s most important cells

Q. Can you explain in more detail why you consider this a “landmark” study?

A. The 2008 HIV study was the first to show one of the ways meditation affects the immune system. The CD4 T cells are the “brains” of the immune system. Because of this study, we now know that meditation directly impacts the immune system’s most important cells—and prevents their decline.

The lead HIV researcher commented on the far-reaching implication of this study: “Given the stress-reduction benefits of meditation training, these findings indicate there can be health protective effects not just in people with HIV but in folks who suffer from daily stress.”

Q. For meditation’s benefits on the immune system to be lasting, I assume there must be ongoing meditation?

A. Yes, that’s true. One early study showed that a single 20-minute meditation could significantly reduce the unhealthy oral bacteria in patients whose gum disease did not respond to standard dental treatments. Amazingly, that single meditation caused a reduction in unhealthy bacteria count which persisted well beyond 24 hours. For lasting effects, however, regular meditation is necessary.

The first long-term study of meditation

Q. Have there been any long-term studies of the effects of meditation on stress and disease?

A. Yes. The results of the first long-term study of meditation, which I consider another major breakthrough, were published in 2012. This study shows that meditating 20 minutes, one to two times a day, for ten years can significantly reduce the risk of heart attack and stroke in adults with heart disease.

For the 2012 study, researchers divided 200 adults with heart disease into two groups: one group was taught to meditate for twenty minutes twice a day; the other group was encouraged to spend a similar amount of time exercising and preparing healthy meals, activities which physicians usually recommend for patients with heart disease.

After nearly a decade, researchers found that those who had meditated for twenty minutes twice a day had reduced their risk of heart attack and stroke by 66% percent compared with those who hadn’t. The risk of heart attack and stroke for those who meditated twenty minutes a day eight times a week (essentially once a day) dropped by nearly 50%. The meditators also reduced their blood pressure and reported feeling better able to control their anger.

Most people today understand the importance of the kind of lifestyle changes that we now recommend routinely in medicine to improve health and reduce risk of premature death — better diet, more exercise, sufficient sleep, reduced stress. If we monitored people with heart disease who made these lifestyle changes over a ten-year period, they would have a lower risk of heart disease and stroke than people who don’t pay attention to these things.

But when, along with these normal lifestyle changes, people add in meditating for twenty minutes 8-14 times a week, they can reduce their risk of heart attack and stroke by an additional 50% to 66%.

A cornerstone of preventive health care

Q. Do you think these recent studies will encourage more physicians to recommend meditation?

A. Yes. I think meditation will become one of the cornerstones of good preventive healthcare along with a good diet with plenty of fresh fruits and vegetables; regular exercise; adequate sleep; and paying attention to stress levels by trying to lead a balanced life. Meditation is the last aspect of preventive health care that has not been adopted broadly as a therapeutic tool.

Q. Is there resistance in the profession to seeing meditation as a therapeutic tool?

A. Not nearly as much as there was even a decade ago. It’s become much more common to see meditation courses offered in hospitals for patients or training courses offered for physicians on how to teach patients to meditate in a short time. Physicians are becoming aware of the benefits of meditation, including its disease-prevention effects.