Article

Sleep and Stress - Their Dynamic Relationship and Impact on Health

Penny M. Kris-Etherton, PhD RD FAHA FASN FNLA 
Evan Pugh University Professor of Nutritional Sciences 
Department of Nutritional Sciences 
Penn State University 
University Park, PA 16802 

 

Introduction 

A central tenant of life is that people want to be happy and healthy.  Of course, there are many other “wants”, but these two are the basis for both psychological and physical well-being.  Many factors affect happiness and health including stress and sleep that have can far reaching consequences on psychological and physical well-being.   

 

We all know how important a good night’s sleep is on all we do the next day.  Good quality sleep is essential for long-term well-being.  Likewise, we all know stress all too well and the need to be able to manage what is at the “doorsteps” of our emotions for psychological well-being in the short term and throughout life.  Simply put, too little sleep and too much stress (as well as the inability to manage it) is not good for our well-being.   

 

Our sleep practices and stress management skills have such a widespread impact on daily life.  Many lifestyle behaviors (like eating healthfully, exercising regularly, managing body weight, avoiding tobacco) and health factors (such as blood pressure, blood glucose and lipid/cholesterol levels, inflammation, coagulation) are affected by perturbations in sleep and being “stressed out”.  It is so important to appreciate that sleep and stress are linked.  For example, having too much stress can compromise sleep quality and likewise, poor sleep can be stressful.  Thus, optimal well-being requires both healthy sleep and minimizing stress. 

 

The purpose of this article to discuss the health benefits of good quality sleep and the importance of managing stress.  Recommendations for sleep and strategies for achieving high quality sleep, as well as strategies for reducing stress will be discussed.  Meeting recommendations for sleep quality and stress management are integral for health, happiness and well-being.   

 

Sleep 

Good sleep practices are needed for overall health, including psychological well-being and brain performance.  Poor sleep quality sleep increases risk of many diseases such as cardiovascular disease, type 2 diabetes, obesity, depression and dementia.  In fact, poor habitual sleep significantly increases risk of all-cause mortality.   In addition to affecting major chronic diseases, insufficient sleep causes many injuries related to motor vehicle crashes and other accidents each year. 

 

Sleep does wonders for the brain and body.  Sleep is essential for learning, concentrating, and remembering things.  In the past decade an important discovery was made about the brain being similar to a waste disposal network (termed the glymphatic system).  Normal brain metabolism generates wastes that need to be cleared which happens during sleep.  While asleep, waste-filled fluid in the brain is flushed out with new (and “clean”) fluid resulting in removal of waste products out of the brain to the circulation for clearance from the body.  Interestingly, some scientists believe that the malfunctioning of this waste disposal system may contribute to the degeneration of brain cells following traumatic brain injury.  It may even contribute to other brain disorders such as age-related loss of cognitive function.  So, sleep is simply not “down time” for the brain but an essential time for a tired brain to prepare for the next wake cycle.  Beyond brain health, sleep benefits everything from blood vessels to the immune system.  Blood vessel dysfunction increases risk of many chronic diseases, and adversely affects many organs such as the heart, kidneys and lungs.  In addition, a compromised immune system increases risk of infectious diseases.  It is without question, that healthy sleep is essential for good health. 

 

So, How Much Sleep Do We Need and How Much Do We Sleep? 

According to the Sleep Foundation, younger adults (18-25 years) and adults (26 to 64 years) need 7 to 9 hours of sleep daily.  Older adults (>65 years) need a bit less sleep, 7 to 8 hours. 

While these are the sleep guidelines, the Sleep Foundation reports that about 35% of US adults get less than the minimum amount recommended (7 hours).  Tellingly, approximately 50% of all Americans report feeling sleepy during the day about three to seven days each week.  Also, sleep quality declines in older adults.  Thus, it is clear that among adults in America there is a “sleep problem”.  And, while many try to catch up on lost sleep during days off from work, school, etc., this is not enough time to make up for one week of too little sleep.  In fact, some studies have shown that an irregular sleep schedule is associated with higher body weight and problems controlling blood glucose.  Along with not getting enough sleep because of our busy schedules, there are also sleep disorders such as insomnia and sleep apnea which result in inadequate.  These typically require medical attention, whereas for most people who aren’t getting the recommended amount of sleep, it’s possible to “fix” the problem simply by prioritizing adequate sleep and adjusting daily schedules to meet sleep recommendations. 

 

Too little sleep is bad, however, too much sleep also has adverse health consequences (> 9 hours per day) and can increase the risk of diabetes, heart disease, stroke, and death.   

Hypersomnia is a sleep disorder characterized by excessive daytime sleepiness resulting in the need to sleep a lot.  This sleep disorder also requires medical attention. 

 

Tips for Healthy Sleep 

According to the Sleep Foundation, better sleep can be achieved by paying attention to sleep hygiene.  Having daily routines, as well as a conducive bedroom environment are recommended for healthy sleep.  A consistent sleep schedule, a comfortable bedroom without disruptions, a relaxing pre-bed routine, and following healthy lifestyle behaviors can promote optimal sleep hygiene. 

 

Stress 

Stress is defined as a feeling of physical, emotional or psychological tension.  Stress is prevalent in the U.S.  According to a 2022 poll conducted by the American Psychological Association, a large majority of adults reported being stressed for many reasons, citing inflation (83%), violence and crime (75%), the current political climate (66%), and the racial climate (62%), among others.  Some signs of stress include being worried, angry, irritable and unable to focus and feeling sad. 

 

Stress is associated with health consequences with about 75% of adults reporting that they have experienced headache (38%), fatigue (35%), feeling nervous or anxious (34%), and/or feeling depressed (33%) due to stress in the past month.  Other health consequences of chronic stress include anxiety and depression, digestive problems, muscle tension and pain, cardiovascular disease (including heart attacks, high blood pressure and stroke), sleep problems, weight gain (leading to overweight and obesity), impaired memory and concentration.   Furthermore, stress is related to unhealthy lifestyle behaviors such as poor diet quality, physical inactivity, use of tobacco, alcohol, and other drugs, and poor sleep hygiene, which contribute to the health consequences of chronic stress.  In contrast, optimism (a sense of hopefulness and confidence that things will work out well) is associated with healthier lifestyle behaviors such as participating in more physical activity, no tobacco use, high diet quality, and better sleep hygiene.  In addition, optimism is associated with healthy aging and lower risk of all-cause mortality, as well as incident CVD events.   

 

Managing Stress 

Stress is ever-present for all of us.  The key is to effectively control it to prevent unhealthy lifestyle practices and consequent health problems.  Stress can’t be avoided but it can be managed with these recommended strategies (from the National Institutes of Health and The American Psychological Association):  

  • Consume a healthy diet and practice mindful eating (i.e., eat to appetite) 
  • Practice meditation, yoga, and deep-breathing techniques 
  • Seek mental health counseling and find a social support network 
  • Balance work and life activities to achieve work-life balance 
  • Schedule fun activities or hobbies at least once per week.  Pursue an activity that is relaxing and soothing. 
  • Exercise regularly.  Even a short walk can boost mood 
  • Review daily accomplishments and focus what has been done not what hasn’t gotten done 
  • Set realistic (and achievable) goals for the day, week and month  

 

Strategies to Prevent Stress 

The age-old adage is apropos – it is better to prevent a problem than try to cure it.  Thus, some strategies to implement (from the Cleveland Clinic) are: 

  • Engage in relaxation activities, which include meditation, yoga, tai chi, breathing exercises and muscle relaxation. There are many programs available online and in-person. 
  • Take care of yourself by eating healthfully, exercising regularly and getting enough sleep. 
  • Think positively and practice gratitude, be thankful for your gifts. Be accepting of life events that can’t be controlled.  Beyond this, control the controllable.   
  • Say “no” to taking on new tasks that are overwhelming. 
  • Interact with people who provide emotional support and help with coping.   

 

Sleep and Stress 

Sleep and stress are life partners that profoundly affect health.  As discussed, they are bi-directionally linked. For example, those with high stress levels are less likely to meet sleep guidelines and poor-quality sleep adversely affects our ability to manage stress.  Thus, to reduce stress, in addition to implementing stress-reduction strategies, optimal sleep hygiene must be attained.  Likewise, to treat poor sleep quality, it is essential to implement effective stress reduction and management strategies.   

 

Conclusion 

In conclusion, stress and sleep play a pivotal role in health.  It is important that they are addressed as partners in health since they are so intertwined.  Effectively addressing sleep hygiene and stress will benefit other healthy lifestyle behaviors that provide further health benefits, including both physical and psychological well-being.   Achieving good health and happiness is an important life goal for everyone.  As the famous English playwright, Shakespeare, shared in MacBeth about the importance of sleep and well-being, “Sleep that soothes away all our worries”.  Similarly, the acclaimed French writer, Voltaire wrote, “I have chosen to be happy because it's good for my health”.   These quotes illustrate what humankind has known for eons that both sleep and happiness are good for the soul.