“Does sleep loss cause low testosterone?” I hear it asked by firefighters at almost every sleep deprivation training class I teach. Don’t hate the messenger, but the answer is yes. In this article, we will look at the reasons. More importantly, we will address how we can fix it amidst increasing call volume that occurs in the middle of the night.
First, we must understand what’s happening in the body. For starters, the body primarily produces testosterone while we sleep. So, it’s a pretty obvious deduction that the longer you are awake, the less testosterone the body will make. This virility hormone is known not only for sex function but also bone density, muscular strength, and mental focus.
The University of Chicago performed a testosterone and sleep study on young healthy men that was published by the Journal of the American Medical Association in 2011. The study found that the testosterone levels of the male participants dropped by 10-15% when sleep was restricted to 5 hours per night in as soon as just one week. This drop was measured in comparison to the participants’ baseline T levels found in 7-8 hours of sleep per night.
During the study, these sleep-deprived men unanimously resulted in progressive decreases in muscular strength, energy, concentration, and vigor–congruent to their testosterone drop. What does this equate to in terms of health? Through normal aging, men’s testosterone levels naturally lower approximately 1%- 2% annually, so after just one week of sleep deprivation, men have the levels of testosterone of men 10 to 15 years their senior. Sleep deprivation quite literally accelerates the aging process.
To understand further reasons of low T in the fire service, we must look at rates of sleep apnea, which is a serious sleep disorder found to be associated with low testosterone. How many firefighters do you personally know that use a CPAP (continuous positive airway pressure) machine–or maybe should? Perhaps you are a firefighter reading this who uses a CPAP machine or have been recently diagnosed with this sleep disorder.
According to a study of 6993 firefighters who were screened for common sleep disorders, almost 40% of them were diagnosed positive with a sleep disorder; the majority were found to have sleep apnea followed by insomnia and work shift disorder. Sadly, 80% of these firefighters who screened positive for a diagnosable sleep disorder had been unaware and untreated prior to the study (Dr. Barger, Harvard). Many firefighters I know tell me that getting diagnosed with sleep apnea and using a CPAP machine changed their life–and their spouse’s life–for the better.
There is also a growing field called Myofunctional Therapy, in which a specialist works with a client to corrective breath practices and to strengthen muscles to enhance the airway. Those who seek this type of clinical support report that they sleep better, have more energy, and have reclaimed their health.
What exactly is the disorder? Obstructive sleep apnea, the type of apnea most firefighters have, is associated with excessively heavy snoring, choking sounds, or pauses in respiration during sleep. This disorder is appropriately named after the Greek word apnea, which means “without breath.” There is a collapse to the airflow due to relaxed or weakened neck muscles, excess neck fat, or a large tongue, resulting in a cessation of breathing, which limits oxygen to the brain and body. It profoundly interferes with the circadian rhythm.
Sleep apnea disrupts access to regenerative slow-wave Delta sleep and REM (rapid eye movement) sleep. Sometimes individuals never enter REM sleep at all, a critically restorative phase when dreaming occurs and when testosterone levels peak and maintain. The overall impact prevents the cardiac, immune, and metabolic systems from resetting and functioning properly. Breathing cessations can occur dozens, or even hundreds, of times per night, lasting for seconds to even minutes. If left untreated, the consequential risks, coupled with the effects of low testosterone levels, include high blood pressure, irregular heartbeat, heart disease, stroke, type 2 diabetes, and something we are all familiar with: daytime fatigue (Johns Hopkins Medicine).
Here’s the double whammy. As a direct response to sleep loss, the body releases a cascade of stress hormones, which cause an increase to blood pressure, a lowering to the immune response, and an unleashing of a pitbull-like grip to hold onto body fat, stored specifically in the mid region. Sleep deprivation and sleep apnea, experienced either independently or combined, regardless, lead to excess weight.
Dr. Eve Van Cauter, a leading sleep scientist, with a team of researchers found that sleep-deprived individuals not only experience starkly elevated stress hormones like cortisol that cause fat retention but they also experience an increase in the hunger hormone (ghrelin) that profusely increases when an individual has reduced sleep, resulting in impulsive eating. Their findings were impactful: Individuals who sleep 6 hours or less, on average, consume 70,000 extra calories annually, which translates to 10 to 15 pounds of weight.
More concerning is the precursor pathway. Cortisol and testosterone share the same precursor for production (think of your hormones like a cake batter–you need all the ingredients for it to come out just right), and when the body has a stress response (such as waking in the middle of the night–even for the most standard call), the body will triage its precursor resources toward the immediate need to secrete cortisol for the body to be awake, and the application for the precursor to go toward testosterone production is robbed, leaving the body at a propensity for lower growth hormone levels.
The good news is, if you learn to reduce stress hormones naturally, the body will balance its growth hormone. This is relevant for both men and women.
Let’s now look at the causation for the prevailing sleep disorder in the fire service. While obesity and higher levels of fat in the neck area are often cited as a cause of sleep apnea, it is a true case of which came first, the chicken or the egg. We know for a fact that circadian disruption (i.e., running calls in the night) leads to weight gain. Regardless of which causes which, it’s an ugly downward cycle.
And not all fat is made the same. Different from subcutaneous fat, abdominal fat, caused by sleep loss, is visceral and it goes deep, enveloping the intestines, pancreas, and liver organs in a dangerous way. It causes an expression of an enzyme called aromatase, which triggers the conversion of male hormone androgens to estrogen, massively lowering testosterone health. A cascade of physiologic effects ensues, causing a disruption to other hormones and health functions. “All of these factors eventually contribute to the CHAOS Complex: coronary disease, hypertension, adult-onset diabetes mellitus, obesity and/or stroke as permanent changes unfold. Other consequences of the chronic hypogonadal state include osteopenia, extreme fatigue, depression, insomnia, loss of aggressiveness and erectile dysfunction all of which develop over variable periods of time.” (Cohen; Aromatase, adiposity, aging and disease. US National Library of Medicine National Institutes of Health.)
This adage is true and false: “If a firefighter has excess fat, all he needs to do is work out more.” My theory is backed by research that proves to rid the body of visceral fat, yes, the body must work out, but equally, if not of higher importance, the body must experience regular, routine stress relief and restorative, high-quality sleep. Stress reduction practices, done before bedtime, actively reset hormones by engaging the parasympathetic nervous system. This may include practices such as a 20-minute walk, a magnesium bath, gentle restorative yoga, qi-gong, meditation, and slow breath practices with an emphasis on prolonged exhalation. The parasympathetic nervous system resets and renews all systems of the body, and it must be engaged to experience deep, quality, restful sleep, which in turn supports ideal weight, heart health, muscle mass, and healthy testosterone levels.
We have created a set of stress-reduction practices that activate the parasympathetic nervous system response and can be done simply in minutes at the firehouse. These practices have been studied and proven to lower blood pressure, reduce stress hormones like adrenaline and cortisol, calm and restore the nervous system, and improve sleep patterns. As one first responder recently said in a feedback form, “Every first responder should be required to take this course and learn these skills.” The fire service should be doing everything possible to maximize quality of sleep to regain healthy testosterone levels and reclaim healthy firefighter lives on and off the job.”
References
Barger, Laura et al. Common sleep disorders increase risk of motor vehicle crashes and adverse health outcomes in firefighters https://pubmed.ncbi.nlm.nih.gov/25580602/.
Leproult Rachel, Van Cauter Eve. Effect of 1 Week of Sleep Restriction on Testosterone Levels in Young Healthy Men https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4445839./
Luboshitzky R et al. Relationship between rapid eye movement sleep and testosterone secretion in normal men Endocrine Institute, Haemek Medical Center, Afula, Israel.
https://www.ncbi.nlm.nih.gov/pubmed/10591612.
A Possible New Approach to Sleep Apnea Institute for Medical Engineering and Science
http://imes.mit.edu/possible-new-approach-stopping-obstructive-sleep-apnea/ .
Bio:
Jacqueline Toomey co-created the First Responder Sleep Recovery Program with her firefighter husband, Sean Toomey. She received her B.A. from Regis University, completed masters-level coursework in education at Metro State University, and trained in Nutrition Therapy. As a Yoga Alliance E-RYT certified instructor with over 1,000 certification hours, she integrates various modalities for mind-body healing in an accessible and effective way for first responders. The Toomeys provide a train-the-trainer certification program and teach across the United States and Canada.
Photo Credit
