Another link between stress and chronic disease has been found in a small, observational study from Deakin University in Australia.
Overweight and obese men secrete higher levels of the stress hormone cortisol in their bodies after eating, which could make them more susceptible to developing chronic diseases, according to the research. The results of the study will be presented this Saturday at the The Endocrine Society's annual meeting in San Francisco.
Study participants included 19 men with a healthy body mass index between 20 and 25, and 17 overweight or obese men with a BMI of 27-35, all between the ages of 50 and 70. The subjects were all asked to prepare and consume a lunchtime meal with the same caloric content and the same amount of protein, fat and carbohydrates. Using a test called enzyme immunoassay, saliva samples were collected to test their cortisol levels 15 and 30 minutes before the men ate lunch, and then again every 15 minutes for 90 minutes after eating.
The overweight and obese men exhibited significantly higher cortisol levels after eating than the normal-weight men: While the men of healthy weight showed a 5 percent increase in salivary cortisol levels after consuming a meal, the cortisol levels of the overweight and obese men increased by 51 percent.
"This research indicates that when we are carrying excess fat stores, we may also be exposing our bodies to increased levels of the stress hormone cortisol every time we have a meal," the study's lead author Anne Turner, Ph.D., said in a statement. "If overweight and obese individuals have an increase in cortisol every time they ingest food, they may be at a greater risk of developing stress‐related diseases."
An extensive body of research has already begun to explore the links between stress and chronic diseases. Studies in the Netherlands found chronically high cortisol levels to be a risk factor in the development of cardiovascular disease, and a 2011 study found that chronic stress can lead to depression. Stress has also been found to help prostate cancer cells survive in the presence of anti-cancer drugs in mice -- but stress management could improve disease outcomes for breast cancer, according to University of Miami research.
"There is evidence that prolonged or chronic stress or exposure to the stress hormone cortisol is associated with greater incidence of chronic diseases such as cardiovascular disease, Type 2 diabetes and mental health problems such as anxiety and depression," Turner told the Huffington Post. "The concern is that frequent repeated exposure to short term or acute stress or elevations of cortisol may also lead to such diseases in the long term."
But the precise reasons why overweight individuals secrete so much more cortisol -- and how cortisol regulation occurs in the body -- are still poorly understood.
"It is thought that the fat cells themselves are somehow involved in regulating cortisol levels in the body but the exact mechanisms for how this occurs are not known," said Turner. "Further research is required to work out the exact reasons for this happening."
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Child's Pose (Balasana)
The calming child's pose is a resting posture that can help quiet the mind, easing stress and anxiety while gently stretching the back. It's also good for the nervous system and lymphatic system, Kennedy notes. "It's one of the key poses that you can come to in the middle of a class whenever you want to to relieve stress," she says. "It's very restorative ... it's child-like and allows us to come inward to ourselves."
Bridge Pose (Setu Bandha Sarvangasana)
Not to be confused with the <a href="http://www.yogajournal.com/poses/473" target="_blank">full wheel</a>, the bridge pose provides gentle stretching of the back and legs while alleviating stress and tension. The pose can reduce anxiety, fatigue, backaches, headaches and insomnia, and is even thought to be therapeutic for high blood pressure. Eva Norlyk Smith, Ph.D., yoga teacher and Managing Editor at YogaUOnline, recommends a supported bridge pose with a block underneath the sacrum as a gentler and more de-stressing way to enjoy the stretch.
Standing Forward Bend (Uttanasana)
Often used as a transition between poses, uttanasana has many benefits when practiced as a pose in itself. The posture stretches the hamstrings, thighs, hips, and is thought to relieve stress, fatigue and mild depression. If your goal is to de-stress in the pose, it's best done with the knees slightly bent, Kennedy says. "It's great for the legs and a lot of different physical things, and it also allows us to calm the mind. You're reversing the blood flow and just hanging out," she says.
Eagle Pose (Garudasana)
The active and empowering eagle pose can help ward off stress by improving concentration and balance, and also by opening up the shoulders, upper back and hips. "Eagle is an empowerment pose because it releases tension in the shoulders, legs and back, and it does require focus for you to remain balanced in it," says Kennedy. "You're literally squeezing the tension out of the body. It's a very active de-stress move"
Corpse Pose (Savasana)
Most yoga practices end with several minutes spent in savasana, and it can easily be the most calming part of the whole thing. The pose puts the body completely at ease and emphasizes total relaxation. Savasana can trigger the body's "relaxation response," a state of deep rest that slows the breathing and lowers the blood pressure while quieting the nervous system. "[Savasana] is <em>the</em> relaxation pose," Kennedy says. "It's actually difficult for many people because we're so not used to being still ... But it encourages the body to come to a more restful state."
Extended Triangle Pose (Utthita Trikonasana)
One of the foundational postures, the triangle pose is an excellent stress-reliever and full-body stretch, <a href="http://www.yogajournal.com/poses/494" target="_blank">according to Yoga Journal</a>. It can also help to improve digestion, and potentially mitigate the symptoms of conditions like anxiety, osteoporosis and sciata.
Legs-Up-The-Wall Pose (Viparita Karani)
Norlyk Smith recommends the resting legs up the wall pose for stress reduction. The pose is traditionally thought to <a href="http://www.yogajournal.com/poses/690" target="_blank">slow the aging process</a>. "It helps renew blood and lymph drainage back into the heart area," she says.
Puppy Pose (Uttana Shishosana)
A variation of child's pose with a heart-opening effect, this mild inversion pose can help to counter our tendency to crouch and slouch the shoulders when stressed, according to Norlyk Smith.
Cat Pose (Marjaryasana)
The cat pose soothes and stretches the lower back, relieving stress while gently massaging the spine. Try arching and rounding the back 10 times in a row while focusing on deep inhaling and exhaling. "[In the cat pose], you're releasing stress in the spine ... If you're in a class, it allows students to begin to slow down and focus on the breath," Kennedy says. "It's one of those transition poses that takes us from the outside world in."
Similar to the downward-facing dog position, except with the forearms on the floor, his standing inversion pose can help to quiet the mind, alleviate stress and reduce anxiety, <a href="http://www.yogajournal.com/poses/2462" target="_blank">according to Yoga Journal</a>. The posture stretches the shoulders, neck and spine.