You heal while you sleep!

Abida Taher, MD, PhDJune 07, 2023

Sleeping well is an important part of cancer care.

"Sleep is an investment in the energy you need to be effective tomorrow” ― Tom Roth

I know how physically draining and psychologically challenging a cancer diagnosis and the ensuing treatment can be. But resilience does not equal endurance. Being able to cope with the changes surrounding a cancer diagnosis is important to be sure, but how you recharge physically, emotionally and psychological after each stressful event is critical. The quicker you can recharge, the faster you can recover. The capacity to recover quickly or being resilient depends on many factors but none so much as on a good night’s sleep.

An estimated 75% of cancer patients and cancer survivors are affected by a lack of quality sleep and sleep disorders – Cancer Medicine

Generally, quality sleep for an adult is when you fall asleep within 30 minutes of getting into bed, sleep soundly through the night with no more than 1 awakening. When/if you do wake up that one time, then you go back to sleep within 20 minutes. More importantly, quality sleep is when you wake up refreshed and ready to take on the new day. There is data showing that cancer patients report insomnia at double the rate of the general population. It naturally follows that caregivers also suffer from insomnia as you can well imagine.

The side effects of cancer treatment and anxiety can negatively impact the circadian rhythms of your body. These rhythms are your body’s response to light and dark and help determine your sleep patterns.

The human body works in finely tuned rhythms. Within your brain, in a part called the hypothalamus, sits a pacemaker or a rhythm generator. It is called the “suprachiasmatic nuclei” and it is the master clock that controls your circadian rhythm. The circadian rhythm is your body’s response to light and dark. It is how your body knows it's time to sleep or to awaken when the sun is up. Circadian rhythms help determine your sleep patterns. This master clock controls the production of melatonin, a hormone that makes you sleepy. The master clock gets its cues or signals from your eyes that sense light. When there is less light, like at night, the master clock tells the brain to make more melatonin so you get sleepy. A disruption in your sleep rhythms causes the body to produce less melatonin, thereby increasing sleeplessness.

It is also true that you heal better when you sleep better. The deepest sleep, the “slow-wave sleep”, occurs in the first part of the night. It is during this time that blood pressure falls, breathing slows down, hormones are secreted and tissue and muscle repair occurs. Research shows that the signals in the brain that modulate the sleep and awake state also act as a switch that turns the immune system off and on. It is not surprising then lack of sleep causes undesirable immune system changes as well.

Without sufficient sleep, your body makes fewer cytokines, a type of protein that targets infection and inflammation, effectively creating an immune response. Cytokines are both produced and released during sleep, causing a double whammy if you skimp on shut-eye” – National Sleep Foundation.

The immune system responds to sleep loss, especially chronic sleep loss, with a general low grade pro-inflammatory state which increases the risk of cardiovascular diseases. Sleep loss reduces natural killer (NK) cell activity, which can increase the risk for cancer and viral infections. On the other hand, your immune system is also responsible for the increased sleep associated with infection. Certain pro-inflammatory cytokines, in particular tumor-necrosis factor and interleukin-1β usually increase sleep, and anti-inflammatory cytokines inhibit sleep.

All of this is to say that sleep is an incredibly important part of cancer healing. The next blog will address simple, effective ways to improve your sleep quality and consequently, your resilience.

Let’s together begin this journey to reclaim good sleep and heal faster.