Thomas Edison famously considered sleeping a “criminal waste of time, inherited from our cave days.”
Russell Foster disagrees with the prolific American inventor.
“We marginalize sleep, and think of it as a luxury,” said Foster, a circadian neuroscientist who studies the sleep cycles of the brain.
But sleep is so much more important than that, he told those attending a recent lecture series at the Center for BrainHealth in Dallas.
His talk explored theories on why people sleep – why they don’t – and how it affects physical and mental health.
Everyone knows that overachiever who manages to tackle the world on two hours of sleep while others can barely manage on six to seven hours and a serious addiction to Americanos, he said.
But, in terms of time best spent, Foster said sleep is the most important thing people do.
A 2014 Center for Disease Control study found about 65 percent of people were getting enough sleep (which to be clear is seven or more hours a night). While those numbers varied from state to state, Texas was slightly higher with 67 percent.
Too little sleep has been tied to increased risks of a number of health conditions, such as obesity, diabetes, high blood pressure, heart disease, and stroke, Foster said. It also can exacerbate mental distress.
Sleep, foster continued, not only allows people to consolidate memories and process information, but also aides in the retention of positive experiences, helps people come up with novel solutions to complex problems, and it helps them process emotions. Yes, sleep therapy is a thing.
But, as people continue to electrify the night and shy away from natural light during the day, body clocks suffer.
Foster said short-term signs of sleep deprivation include loss of attention, loss of empathy, and a declining ability to process information. The long-term impact, he said, can be seen in immune system suppression, and increased cancer rates and cardiovascular disease.
Lack of sleep also can make people fatter, he added.
Sleep disruption, he said causes the hunger hormone (ghrelin) to be released, causing a person to be hungry even when the body doesn’t need food.
According to the National Sleep Foundation, when sleep is restricted to four hours a night, ghrelin levels go up and leptin (the hormone that suppresses appetite) goes down.
So what should people do?
To start, regulating exposure to light is critical, Foster said.
Morning light advances the internal clock, making the sleeper get up earlier the following day, he said. Catching more rays later in the day has the opposite effect.
Foster suggests decreasing light exposure at least half an hour before bed. He also suggested making the bedroom a haven for sleep by keeping it dark and cool. Turn off mobile phones, computers, and anything that will excite the brain.
One last tip, don’t drink caffeine after lunch.
Listen to the body, Foster said. “If you are dependent on an alarm clock to get up … you’re not getting enough sleep.”