It’s that time of year when schedules somehow seem three times more full with work, school, and social gatherings, but the days seem shorter. On TV and in newspapers, articles appear weekly on ways to reduce holiday stress. Holiday cheer and spending time with family can keep us afloat during the holiday season, but when the holidays are over and life returns to normal, what happens when the stress doesn’t melt as fast as the snow?
Due to economic changes and an increase in unemployment rates, many Americans have reported more stress over the last year. Frequent feelings of stress can get under our skin and damage our body. While stress does not contribute to ulcers, a popularly held belief, stress does have long-term effects on health. Stress has been linked to low immunity to common illnesses, depression, high blood pressure, and heart disease.
There are numerous stress reduction techniques that can help maintain health, such as diet, exercise, and relaxation. One ancient form of stress reduction is receiving renewed attention by health professionals. Transcendental meditation, once popular in the 1960s and 70s, is thought to have physiologic effects on the body that reduce the damaging effects of stress. The National Institutes of Health have spent over twenty million dollars on researching transcendental meditation and its possible effects on blood pressure, heart disease, and the immune system. While this is a small sum compared to other medical studies, research in alternative medicine is growing.
New studies involving Transcendental Meditation
Last month at the American Heart Association conference in Orlando, FL, researchers presented data on a nine-year study that looked at the effects of transcendental meditation (TM) on heart disease in a group of African-American patients with high blood pressure and heart disease. The study was a clinical trial that randomly assigned half of the 201 patients to practice TM twice daily while the other half received health education only. After nine years, 80% still practiced TM at least once per day and the data showed this group had 20 cardiovascular events (heart attacks, stroke, or death) compared to 31 in the group that received health education alone, a statistically significant difference. The two groups had similar lifestyle habits in terms of diet and exercise, but reported significantly less stress and had reduced systolic blood pressure by 5mmHg.
Several other recent studies have also examined the relationships between transcendental meditation and health outcomes. One study found TM decreased stress and blood pressure in college students. Another showed that older breast cancer patients significantly reduced their stress and improved their quality of life after practicing transcendental meditation twice daily.
While finding effective methods of reducing stress and risk of cardiovascular disease without the use of drugs is promising, these studies have been relatively small, and larger studies with a more diverse population are necessary to confirm whether transcendental meditation is indeed as powerful as these studies suggest.
Clearly, many individuals are benefitting from the technique. But how does meditation reduce stress and the risk of heart disease? First, we should understand how stress impacts our health.
How stress gets under our skin
We all experience stress at one time or another. There are different kinds of stress, and not all stress is negative. Acute stress is more immediate stress that we deal with in everyday life. Eustress, positive acute stress, provides us with energy when running a race or completing a deadline. It also causes the exhilarating feeling we get when doing things like riding a roller coaster or skiing down a steep slope. Negative acute stressful situations are those we tend to associate the word stress with: forgetting to study for a test, arguing with a friend or co-worker, or having a flight delayed due to bad weather. We may be stressed for a few minutes, hours, or a day or two, but eventually the problem is resolved and we return to a peaceful state.
The physiologic response to stress is controlled by the autonomic nervous system, the involuntary part of our nervous system that controls heart rate, blood pressure, and digestion. There are two branches to the autonomic nervous system: sympathetic and parasympathetic. The sympathetic nervous system prepares our body to react to stress (“fight or flight”) and the parasympathetic helps us recover from stress (“rest and digest”). When we are stressed, our body releases chemicals that temporarily improve performance. Cortisol, adrenaline, and other stress hormones increase heart rate, slow digestion, and increase blood pressure, all to allow greater blood flow to our muscles, heart, and brain to be able to think or act quickly in the face of immediate or acute stress. The body is able to recover from acute from stress via a natural feedback loop with the brain. High levels of stress hormones in the blood signal to the brain to stop producing the stress hormones so we can rest and recover from the stressful event.
Sometimes stress can seem more like a way of life. Chronic stress is ongoing stress that seems endless, such as a demanding job, difficult family life, or experiencing ongoing hardship. This type of stress is the most damaging to our health. With acute stress, once the perceived threat has passed, the parasympathetic nervous system takes over, allowing us to relax and recover from the stressful event. But during chronic stress, the body is continually exposed to the hormones that regulate stress. The system’s natural feedback loop is interrupted. The relaxation response is not activated, and the pathway that regulates cortisol is shut down, rendering it unable stop the effects of the stress. It is the constant activation of the stress response that leads to the negative health outcomes seen with chronic stress.
The primary stress hormones are cortisol, epinephrine (also called adrenaline), and norepinephine. Cortisol is a steroid hormone released from the adrenal glands, which sit above the kidneys. Epinephrine is also released from the adrenal glands. Norepinephrine is a neurotransmitter that helps the body and brain communicate with each other about stress and about how the body should react physiologically to stress. When cortisol is released in response to stress, it works with the other stress hormones to prepare the body to react to the stressful event. The breakdown of fat leads to increased blood sugar, helping to provide energy for the essential organs – brain, heart, and lungs (more on this later). Cortisol makes blood vessels more responsive to epinephrine and norepinephrine, and in turn these hormones constrict blood vessels to increase blood pressure. In addition, epinephrine acts to increase heart rate. Increased blood pressure and heart rate help deliver nutrients and oxygen faster to the organs that need them most. Acting together, stress hormones ensure that we can think and act quickly and clearly in stressful situations.
In addition to creating the emergency response, stress hormones also divert energy away from non-emergency functions like digestion, reproduction, and maintaining the immune system. For example, cortisol inhibits the immune system by preventing the production of T-cells, important players in the immune system, and by interrupting the distribution of other immune cells to the lymph nodes and bone marrow.
Because stress hormones suppress non-emergency functions, such as maintaining the immune system, chronic stress can leave many bodily systems at risk. Constant suppression of the immune system, for example, leaves us vulnerable to infections. Additionally, as mentioned above, to provide the body with extra energy to deal with stress, stress hormones stimulate the breakdown of stored fat into smaller fatty acids that we can use for short-term energy. These fatty acids, called triglycerides, enter the blood stream waiting to be taken up by our muscles to be used for quick energy if we need flee a stressful situation. This is likely an evolutionarily advantageous response to stress: earlier in time, stress probably meant running from a dangerous situation, and the free fatty acids gave our muscles energy. But if we don’t use the fatty acids for energy through a physical outlet, the fatty acids remain in the blood, eventually causing high cholesterol. Thus, chronic stress leads to high blood pressure and cardiovascular disease, especially in combination with the stress hormones’ direct effects on increasing blood pressure. When we have high blood pressure, our heart rate increases and blood flows more vigorously through our veins and arteries. Branch points in arteries can receive small injuries from the quicker flow of blood. The immune system then repairs arteries, but this process can lead to the deposition of plaque in the damaged areas. These little clots in our arteries block the free flow of blood, causing heart disease. Exercise is a great way to prevent this negative series of events: in addition to providing endorphins that makes us feel better, exercise uses the triglycerides in our blood stream so there are less to become trapped in our vessels as plaque.
As we can see, chronic activation of the stress response can lead to host of health problems. De-stressing and activating a resting state is important for maintaining proper balance between the sympathetic and parasympathetic nervous systems. Transcendental meditation may help to achieve this relaxation response.
Reviving Transcendental Meditation from the Vedas
Based on traditional Indian medicine, known as Ayurvedic medicine (ayus meaning life and veda relating to knowledge or science), transcendental meditation is thought to be one of the most widely practiced meditation techniques in the world. It originated over 5,000 years ago through the teachings of the Hindu god Krishna in the Bhagavad Gita; it was then lost and re-discovered several times throughout Indian history. In 1955, an Indian man named Maharishi Mahesh Yogi began teaching a style of meditation that later became known as transcendental meditation. Maharishi spent the 1950s and ’60s traveling around the world sharing his meditation technique and other forms alternative medicine that emphasize the Ayurvedic values of mind-body balance. Maharishi trademarked Transcendental Meditation and Maharishi Vedic Approach to Health in the 1980s in the United States.
Transcendental meditation is described as spiritual – rather than religious – meditation, and the official Transcendental Meditation website (www.tm.org) describes transcendental meditation as a mental health relaxation technique. Formally, the technique is taught in a seven step course that includes both group lectures on the potential benefits and mechanistic explanations of TM, as well as individual instruction in meditation techniques. Transcendental meditation is supposed to be practiced for 20 minutes, two times per day. No chants are uttered aloud, nor is the individual taught to practice mantras; rather the technique is to focus on a specific thought to bring the mind’s attention to that thought and away from the racing thoughts about the day’s stressful events. The technique is designed to provide “restful alertness” and to bring the individual’s thoughts to a peaceful level of consciousness, a quieter mental state. In medical studies involving transcendental meditation, all participants assigned to transcendental meditation received formal training by certified instructors.
The physiologic benefits of transcendental meditation do seem related to activating the parasympathetic and quieting the sympathetic nervous system. Medical studies have showed that individuals who practice transcendental meditation daily had lower blood levels of epinephrine, norepinephrine, and cortisol. Transcendental meditation also led to lower respiration rates and heart rate and better blood flow to the brain, indicating less constriction of blood vessels. A few studies have compared transcendental meditation to simple relaxation. One such study showed no difference and the other showed that the meditators had lower cortisol levels than then relaxers. In long-term studies, EEGs of individuals who practiced transcendental meditation showed significantly different EEG waves, indicating higher states of consciousness. Another study showed practitioners completed simple tasks more efficiently than non-meditators.
There are small, but concerning downsides to the transcendental meditation. Some earlier studies proclaiming the benefits of TM failed to report that the researchers had financial ties to the Maharishi Vedic Approach to Health. While more recent studies have disclosed associations with Maharishi’s trademark, training in transcendental meditation is quite expensive. The course can be up to $1500 and requires travel to Iowa; experts in transcendental meditation claim it is not a practice that can be learned from a book or DVD. Some skeptics have gone as far as saying transcendental meditation is a scam and its practitioners cult-like.
Reviving transcendental meditation and bringing it in to the world of modern medicine may provide benefits to some individuals. However, more studies are needed to confirm the physiologic benefits. If it does prove to be as effective as promised, it is hoped that learning the technique will become more accessible and affordable. For now, perhaps the best way to reduce stress and its harmful effects is to exercise and take time out each day to practice some form of relaxation, whether it is meditation or simply allowing our minds to rest and not dwell on what keeps us feeling anxious. It may bring us better peace of mind and help restore balance in the autonomic nervous system.
–Megan Lee, Harvard Medical School
For More Information:
APA Stress Survey: Children are More Stressed Than Parents Realize:
< http://www.apapracticecentral.org/update/2009/11-23/stress-survey.aspx >
New York Times article: Can Meditation Curb Heart Attacks?:
< http://well.blogs.nytimes.com/2009/11/20/can-meditation-curb-heart-attacks/ >
Washington Post article: From incarceration to meditation?:
< http://www.washingtonpost.com/wp-dyn/content/article/2009/12/13/AR2009121302680.html >
BBC article: Meditation eases heart disease:
< http://news.bbc.co.uk/2/hi/health/8363302.stm >
Schneider R. et al. Abstract 1177: Effects of Stress Reduction on Clinical Events in African Americans With Coronary Heart Disease: A Randomized Controlled Trial. Circulation. 2009. 120:S461.
Nidich S. et al. A randomized controlled trial of the effects of transcendental meditation on quality of life in older breast cancer patients. Integr Cancer Ther. 2009 Sep;8(3):228-34.
Nidich S. et al. A randomized controlled trial on effects of the Transcendental Meditation program on blood pressure, psychological distress, and coping in young adults. Am J Hypertens. 2009 Dec;22(12):1326-31. Epub 2009 Oct 1.