Sleep, Stress Management and Cancer Prevention

03/31/2014 01:01 pm ET | Updated Mar 31, 2014

Many of us have learned that a diet rich in fresh vegetables, fruits and whole grains, daily physical exercise, and protecting our skin from the sun can significantly reduce our cancer risk. Ending smoking and limiting alcohol are also high on the list of ways to prevent cancer.

But how often do we realize that adequate sleep is necessary to maintain a strong immune system, to prevent the growth of cancer? Do we actively seek to manage stress in our daily lives so that we will not be harmed by its effects on our bodies and mind?

In her new book, Thrive, Arianna Huffington has shared her experiences as a person who's learned the value of quality sleep and stress reduction. In a world where women and men are advised to "lean in," run faster and reach higher, Arianna Huffington has courageously redefined the meaning of success.

What does this have to do with cancer? Simply stated, our bodies and mind are closely connected, and that which affects our state of mind will invariably affect the way in which our bodies function. That is the reason why adequate sleep and stress reduction are of critical importance to cancer prevention.

One highly-regarded cancer researcher told me, "Each day we fight off cancer cells." In order to win that battle, we need to support and maintain our immune systems.

In 2003, a study by Patel, Ayas and others from the Harvard School of Public Health and Vancouver Hospital, British Columbia, reported that women sleeping six or seven hours each night had a lower mortality risk. In other words, women who had a good night's rest had a reduced chance of dying due to cancer, heart disease, and other causes.

What happens when our sleep cycle is interrupted, as in night shift workers? Schernhammer, Kroenke, and others in 2006 studied over 115,022 nurses working the night shift and found an elevated risk of breast cancer after long periods of rotating night work.

This finding was reinforced by David E. Blask of Tulane University School of Medicine in 2008, who demonstrated that night shift workers and others who are regularly exposed to light at night have a higher cancer risk. Suppression of the immune system results, resulting in a higher risk of breast cancer and other cancers.

In 2012, Cheryl Thompson, Ph.D., of Case Western Reserve University School of Medicine reported that lack of sleep in postmenopausal women is linked to more aggressive breast cancers. Li Li, M.D., Ph.D., a co-author of this study, noted that, "Short sleep duration is a public health hazard leading not only to obesity, diabetes and heart disease, but also cancer."

It isn't surprising to learn that our bodies require adequate sleep to restore and protect our bodies and minds. Most likely, the risk for other cancers, including prostate, lung, ovarian and other cancers, is also linked to the presence or absence of adequate sleep in our daily lives.

When our sleep is insufficient, cortisol and hunger hormones both surge, causing a corresponding increase in insulin. There is a decrease in various hormones, including leptin, melatonin, growth hormone, testosterone, and serotonin, all of which lead to weight gain. When we stay up past midnight, hormonal imbalance results, that often causes us to eat more. Between 10 p.m. and 11 p.m. is the optimal time to begin sleeping.

How can we maximize the benefit of our nightly sleep? Turn off cell phones, computers, televisions, and any other distracting devices before bedtime to establish an atmosphere of calm and restfulness.

Exercise and eating and drinking should end several hours before you are ready for sleep at night. Try not to drink caffeinated beverages in the evening.

Keeping the temperature in your bedroom low -- at 70 degrees or less -- is an aid to restful sleep.

Once we awaken, we should allow natural sunlight to fill our living space. Melatonin, a key hormone involved in sleeping and waking, is supposed to be lowest early in the morning. Persistent darkness will keep melatonin levels in your body high, and you may feel drowsy and unable to fully awaken.

As we begin our day, we are bombarded by natural stressors associated with our family members, coworkers, bosses, friends, and others.

While we cannot completely eliminate stress from our daily lives, we can learn how to manage it properly. A direct link between stress and the development of cancer has not been established. However, it makes good sense to maintain and support a healthy immune system which will fight off many diseases.

How can we manage stress each day? Deep breathing exercises, meditation, keeping a journal, yoga, are all ways in which we can relax and relieve stress.

Having a supportive circle of friends and family members, and keeping a positive outlook on life can also help boost the immune system.

There are many ways in which we can reduce cancer risk each day. Adequate sleep and managing stress are two important elements in our goal to prevent cancer.

Margaret I. Cuomo, M.D. -- Author of A World Without Cancer