Napping reverses the damage caused by poor sleep (SQ-9)
Our body is an amazing machine. Even when we are sleeping, it is working hard, doing amazing stuff at the backend to keep us healthy and rejuvenated. We all know how an all-nighter can make us feel all grumpy, tired and stressed. It is because sleep has a direct impact on the functioning of our central nervous system, the information highway of our body – affecting our mood, internal balance, cognitive and decision making abilities. Sleep deficiency is often cited as one of the biggest reasons for road and aviation accidents. In fact, two of the most tragic nuclear disasters in the recent history such as the 1979 Three Mile Island and the 1986 Chernobyl nuclear reactor meltdown have been linked to the lack of sleep.
Sleep deprivation also creates imbalance in metabolic, hormonal and immune pathways. People who don’t get sufficient sleep for long periods are susceptible to develop diabetes, obesity, cardiovascular diseases, high cholesterol, inflammation, and even depression and anxiety disorders. These conditions affect the quality of life we lead and may even reduce our life expectancy.
It seems sleep is more important than we give it credit for in keeping us healthy overall. But getting enough sleep may be a challenge in today’s hectic and fast paced world. Long working hours, addiction to smart phones and changing lifestyles are contributing to our sleep deficit and the resulting health consequences.
A quick nap may help?
We may have reserved short naps for babies, pregnant women or elderly but there must be a reason why innovative global companies like Google and Apple encourage the concept of power napping during working hours. Studies show that power naps, if taken for less than 30 minutes, can restore alertness and mental efficiency, thereby promoting performance and productivity  .
While napping has a positive effect on mental alertness, does it have the same effect on stress and immunity? A 2015 study published in The Journal of Clinical Endocrinology and Metabolism sheds a new light in this context. It provides substantial evidence that “napping has stress-releasing and immune effects” and even more importantly it reverses the adverse effects that poor sleep exerts on our neuroendocrine and immune system.
Effects of napping on immunity and neuroendocrine stress
The research team analyzed the urine and saliva samples of the participants to understand the impact of restricted sleep and napping on the hormone levels. The study showed that when the participants were allowed to sleep for only two hours in the night, there was an increase in the levels of norepinephrine, a stress hormone involved in the body’s fight or flight response. There was also a drop in the levels of interleukin-6, a protein that helps the body to launch an inflammatory response against any viral attack or injury. This observation suggests that restricted sleep impairs the body’s stress and immune response. But when the participants were given the opportunity to nap, the levels of both the hormones were restored to normal.
Norepinephrine and Interleukin-6: Biomarkers for neuroendocrine and immune health
Have you ever noticed how our body responds to an extremely stressful situation? We feel the blood pumping, our heart starts to beat faster while our breathing increases. It is because our nervous system releases the chemical norepinephrine and gets you ready to respond to the immediate stress – known as fight of flight response.
Norepinephrine is a hormone and a neurotransmitter that along with epinephrine (commonly known as adrenaline) provides the body with much needed burst of energy by releasing glucose into the blood stream, increasing the heart and respiratory rate to make oxygen available to cells. These hormones also increase the blood flow to important organs such as the heart, brain and skeletal muscles where it is needed the most. Continuously high levels of norepinephrine are linked with high blood pressure, headaches, palpitations, anxiety attacks, depression, diabetes and even tremors.
Interleukin 6 (IL 6)
When our body is preparing to fight against any infection, injury or trauma, it signals the immune system to release special proteins called cytokines. Interleukin 6 (IL 6) is one such major cytokine that activates immune response against viral attacks, infections, trauma and even cancer. Low levels of IL 6 in the body suggests decreased ability of the body to fight diseases.
Now this promising research suggests that a brief day-time nap may not only help in re-establishing wakefulness, it may even restore the levels of hormones and proteins directly associated with neuroendocrine stress and immunity – reversing the damage caused by poor sleep. According to Brice Faraut, one of the study authors, “Napping may offer a way to counter the damaging effects of sleep restriction by helping the immune and neuroendocrine systems to recover...The findings support the development of practical strategies for addressing chronically sleep-deprived populations, such as night and shift workers.”
- Takahashi M, Arito H. Maintenance of alertness and performance by a brief nap after lunch under prior sleep deficit. Sleep. 2000;23: 813–819.
- Mednick S, Nakayama K, Stickgold R. Sleep-dependent learning: a nap is as good as a night. Nat Neurosci. 2003;6:697–698.
- Full Text of the study can be downloaded from here: http://hbpleaders.heart.org/resources/item/1/59