Meditation is a centuries-old practice of getting in touch with one’s self, observing thoughts without judgment, and finding peace and ease with the present moment.
Despite what many think meditation is, quieting the mind or shutting the mind off, meditation isn’t about that. It’s about connecting, observing, and letting your thoughts move along without attaching yourself to them. Lately, you may read more or hear about meditation from spiritual gurus to celebrities practicing certain forms of meditation, and media outlets touting the benefits of meditation. But what exactly is the science of meditation?
What can we learn from meditation research about the impact on our physical and mental health?
What is Meditation?
Meditation is a mind-body discipline used to quiet the mind and improve health and well-being (1).
Types of Mediation
Meditation can be guided by an instructor or self-directed. There are many different types of meditation, some of the most popular include:
- Mantra Based Meditation: Mantra means a vehicle for the mind, and is a sound, word or phrase repeated silently throughout the meditation. Transcendental Meditation (TM) is a form of mantra-based meditation.
- Mindfulness Meditation: Draws attention to the present moment and acknowledges current circumstances without judgment.
- Deep Breathing Meditation: Focusses on controlling your breath.
- Progressive Relaxation: Involves progressively relaxing all the muscle groups in the body one area at a time.
- Zen Meditation: Buddhist based spiritual practice that promotes awareness and presence.
- Loving Kindness Meditation: Uses words and images to invoke love and kindness to yourself and others.
Although there are many different types of meditation, most forms include finding a quiet and comfortable place, limiting distractions and directing the focus of the mind. Therefore, during meditation, it’s best to acknowledge and dismiss thoughts as they come up without getting caught up in emotions or feelings.
It is unclear in the current meditation research whether the impact on mind and body varies based on the type of meditation practiced or if health benefits are accessible through all types of meditation (2). What can be agreed upon is that meditation is a way to give your brain a break.
The brain is constantly taking in information. Meditation downshifts this work to allow for deep brain rest. As a result, some studies show that you may need less sleep with regular meditation practice (3). Researchers are just beginning to scratch the surface on the science of mediation including how it accomplishes deep rest and the health benefits associated with it.
What is the Science of Meditation?
Exploring the science of meditation presents some very unique challenges to the academic community. This is because meditation is not like a drug where a specific amount can be given and compared with a placebo-like a sugar pill. It is a unique discipline that varies in practice from person to person. Therefore, it is difficult to measure and compare (4).
Despite the challenges in studying meditation, available research shows many positive changes within both the mind and body. And unlike many other health remedies, meditation has few barriers to practice. It is free, can be done anywhere, and typically requires only a small amount of time.
The combination of health benefits and ease of accessibility of meditation and other mindfulness-based practices is drawing the attention of the medical community. As a result, eighty percent of the accredited medical schools in the country incorporate mindfulness-based interventions (MBI) into the care of patients (5).
Although meditation research is still considered new, what has been done shows promise.
The Health Benefits of Meditation
Meditation influences many important parts of the body – both mental and physical (6), including:
- Brain Function and Neuroplasticity: This is the ability of the brain to change and adapt throughout life.
- The Autonomic Nervous System: This system regulates unconscious activity like heartbeat and digestive function.
- Immune Function: This is the system that fights off infection and protects the body from invaders like bacteria and viruses.
- The Endocrine System: This system regulates hormones.
- Metabolism: Includes essential bodily functions that maintain life, like using food for energy.
As humans, our nervous system has two modes: fight or flight and rest and digest. Fight or flight activates in times of stress or danger. Rest and digest activate in times of relaxation. Meditation science shows that practicing meditation is a way to activate the rest and digest mode. This is the time when the body does all its repair and clean up. So it’s hardly surprising that there are many physical and mental health benefits to the regular practice of meditation.
Studies of individuals practicing a mantra-based meditation showed a decrease in heart rate and slowed breathing during practice as well as enhanced wakefulness (7). This helps us understand that the cognitive state achieved during meditation is different from being asleep or awake. In fact, it is most accurately described as somewhere in between.
Meditation Benefits for Mental Health
A recent review of nearly 50 eligible studies on meditation involving more than 3,000 participants concluded that meditation reduces anxiety, depression, and pain (8). Meditation can also improve our response to stressful life events. Stress is a widespread and complex condition with both mental and physical side effects. In fact, some experts suggest that 60-80% of all doctor visits have a stress component (9). Meditation can reduce physical and mental symptoms of stress and increase the perceived level of control over life events (10)
It’s important to acknowledge that meditation doesn’t eliminate stress. But, it does help to manage our response to stress. In quieting the mind and engaging the relaxation response, we take a break from our stress and have the ability to control how we feel.
Having access to a tool that can be used anywhere, at any time, for free with nearly immediate impact is the perfect remedy to the chronic stress most of us face on a daily basis.
Meditation Benefits for Sleep
Meditation impacts several components of sleep (11), including:
- Reducing hormones that interfere with sleep like cortisol and adrenaline (stress hormones)
- Increasing melatonin, a hormone that helps induce sleep
- Enhancing serotonin, a happiness hormone and a precursor to melatonin as well as noradrenaline
Meditating brings about a state similar to sleep where heart rate, blood pressure, oxygen consumption, anxiety, and arousal are all reduced. Not surprisingly, people who meditate have an easier time getting to sleep (12). It is theorized that the similarities between sleep and meditation make it easier to fall asleep.
Not only do meditators fall asleep faster but their sleep may also be more productive. It turns out practicing meditation improves blood flow to the parts of the brain responsible for executive function while you sleep (13). The executive function of the brain helps us to plan and prepare our day, recall tasks, follow instructions and multi-task. A study exploring meditation and executive function confirmed that meditation does, in fact, relate to greater control over executive function (14).
Meditation Benefits for Physical Health
The mind and body are undeniably connected. Therefore, the physical benefits of meditation relate to and often overlap with mental benefits. The physical benefits of meditation extend into every major organ system. Exploring physical health with meditation research is exciting because it points to benefits that can more easily be measured.
Regular meditation improves cardiovascular health. The cardiovascular system includes the heart and networks of blood vessels that run throughout the body. And cardiovascular disease is the number one preventable cause of death in the United States. Cardiovascular disease includes high blood pressure, heart attacks, and strokes. Programs known to reverse heart disease include diet, exercise, and meditation as components of a complete lifestyle intervention (15).
Meditation is effective at lowering blood pressure in individuals with high blood pressure as well as those that fall into the at-risk category (16). TM has also shown to be effective at lowering cholesterol significantly in less than a year (17). Cholesterol is another factor in the development of heart disease.
Your immune system is also impacted by meditation. Immune function refers to the body’s ability to fight bacteria and viruses to keep you healthy. Most of the meditation research done in this area is with mindfulness meditation. Evidence from randomized controlled trials (one of the strongest forms of scientific evidence) has shown that regular mindfulness meditation reduces inflammation, increases immune function and increases anti-aging activity within the immune cell (18).
In addition to impacting the heart and immune systems, meditation affects hormone production as well. Hormones are the chemical messengers of the body that help things run smoothly. Do you need to get out of a burning building? The hormone adrenaline turns on to help you think clearly and move quickly. Are you carb loading for your big race tomorrow? The hormone insulin turns on to help drive that fuel into your cells.
Hormones are a vital part of a healthy mind and body. But, sometimes stress and lack of rest get in the way of healthy hormone balance. Meditation can be a remedy for haywire hormones. Regular meditation reduces the stress hormones, increases the sleep hormone melatonin when its time to sleep and modestly improves blood sugar balance. (19)(20)(21)
Healthy Body Weight
Positive changes in hormone function may also lead to healthier body weight. Obesity and overweight are complex conditions involving genes, environment, and behavior. So, a well-rounded approach to weight management needs to address all these factors contributing to excess body fat.
Higher levels of stress hormones are associated with obesity (22). Regular mindfulness meditation reduces binge eating and emotional eating behavior (23). Therefore, meditation paired with its not so distant cousins, mindfulness and mindful eating, is a promising approach to treating this complex problem (24).
Meditation Changes the Brain
What mechanism is responsible for all of the health benefits of meditation? Based on meditation research, it turns out that the brain actually physically changes in response to meditation (25). Brain imaging studies within the field of meditation science have consistently shown changes in several areas of the brain (26). These include:
- The prefrontal cortex: this part of the brain is related to attention processes.
- The hippocampus: An important structure for learning and memory processing as well as regulation of the stress response.
- The cingulate cortex: A part of the brain that contributes to self and emotional regulation.
- The amygdala: The area of the brain that initiates the stress response.
- The sensory cortices and insula: parts of the brain that contribute to body awareness (ex. feeling full).
In a study led by a Harvard researcher, the brains of 20 volunteers were assessed with magnetic resonance imaging (MRI) (27). The participants completed a week-long meditation retreat involving full days of Buddhist Insight meditation. This type of meditation involves present moment mindfulness. Meditators experienced physical growth in the areas of the brain that handle sensations of the body like feeling hot or cold, attention and sensory processing.
In addition to changes in cortical thickness, the amygdala or “caveman brain” shrinks in response to regular mindfulness-based practice like meditation and yoga (28). The amygdala is known as the caveman brain because it is responsible for our immediate response to danger, most namely the fight or flight response (29).
Physical changes in the brain are consistent with research highlighting meditation’s impact on mental health and behavior.
How Much Meditation do I Need?
The burning question we all want to know – how much meditation do I need to do to see results? What say, you meditation science gods? Unfortunately, there is no general consensus on a specific amount of time. This is bad news for all us type-A personalities! In reviewing the available meditation research, it appears that any amount is beneficial. But, the more you make meditation a regular practice, the greater the benefits. Therefore, consistency should be the overall goal, not quantity.
Setting a realistic goal is the best start for any new health practice. So, aim for a time that is manageable and that can be done with some regularity. Again, you should focus on quality and consistency over the length of time spent in each individual session.
Morning meditation will set the tone for your day. And if it’s part of your morning routine, you’ll face fewer barriers to practice. But if mornings are not a realistic time for you personally you may consider what other time of day works best. So, think through when, where and how long you’ll practice. And don’t forget about logistics. Sure, you can meditate anywhere – your car, your desk, in the waiting room for an appointment, etc., but ideally, you should find a quiet place with few distractions.