BY SANDI MOYNIHAN | SEPTEMBER 11, 2015
When was the last time someone asked you how well you were sleeping? Chances are, unless you just talked to your mom or visited the doctor, it’s been a while since anyone has taken an interest in your nightly shut-eye habits.
But it turns out that for people looking to live a fit-minded lifestyle, proper sleep habits — in addition to a balanced diet and exercise — are crucial to achieving any health and wellness goals, including weight loss. In fact, new studies show that poor sleep habits, like getting too little or too much sleep, can be enough to hamper the positive effects of maintaining a clean diet and regular workout routine.
So let’s take a break from focusing on diet and exercise and dive into the world of one of the body’s most mysterious and important physiological processes: sleep.
WHAT IS SLEEP AND WHY IS IT SO IMPORTANT?
At its core, sleep is a complex, restorative process that the body does every night to offset all the things it does during the day.
“Sleep is a cleaning process,” said Dr. Helene A. Emsellem of the Center for Sleep and Wake Disorders in Chevy Chase, Maryland. “It’s a resetting and rejuvenating process both for us, physically and psychologically.”
During the day, we are busy moving, learning, and taking in the world around us. From the moment we wake up to the moment we shut our eyes, we are constantly processing information and interacting with our environment, which requires a lot of physical and mental energy. So at night, the body goes to sleep so the brain can sort through all the information we absorbed while we were awake.
“[During sleep] you have to … decide which connections you’re going to fortify and which ones are superfluous and unnecessary and kind of reset your brain so that it’s ready to take on new information again [in the morning],” Emsellem said.
Think of it this way. If your brain was a room, and each day you filled that room up with items, sleep is like the night-time cleaning crew that sorts through all items to make space for any new things you might come across and want to keep tomorrow. Without that night-time cleaning crew coming in to tidy things up, you would eventually run out of room to add more items, and the room would be over-filled.
“So [during sleep] we filter through, prioritize, and stabilize the information we want to keep straight [for tomorrow],” Emsellem said.
SO WHAT HAPPENS WHEN WE RESTRICT SLEEP — EVEN FOR IMPORTANT THINGS, LIKE STUDYING, WORK OR WORKOUTS?
While the body can bounce back from an occasional poor night’s sleep, regularly limiting the amount of time you sleep to less than seven hours — for any reason— is not a good idea.
“In the first third of the night we do most of our slow-wave sleep, which is our physical resetting, but it’s in the second half of the night that we do the majority of our psychological resetting,” Emsellem said. “So when we don’t get enough sleep, we restrict the whole process.”
Also, despite what you’ve heard, it doesn’t matter whether you stay up late or get up early. Cutting yourself short of sleep in any capacity, when done regularly, has its consequences, including an increased risk for obesity, cardiovascular problems, and death.
Even if you’re losing sleep to squeeze in an extra sweat session at the gym, Emsellem notes, digging into your sleep time might actually cause your body to gain more weight.
“It’s just not possible to trade sleep for exercise,” Emsellem said.
WAIT, WAIT, WAIT. LOSING SLEEP CAN MAKE ME GAIN WEIGHT, EVEN IF I WORK OUT MORE? THAT DOESN’T MAKE SENSE!
Actually, it does. Let’s take a look at two of the body’s hormones, called leptin and ghrelin. In the most basic of explanations, leptin’s job is to tell the body how many calories to absorb, while ghrelin, its sister hormone, helps control appetite.
One of the ways leptin decides how many calories to absorb is based on how rested we are. When we don’t sleep enough, leptin assumes we are in danger and tells the body to absorb more calories, causing us to gain weight. Then, because leptin is telling the body to store fat, ghrelin orders the hypothalamus to increase appetite, causing us to eat more.
“In the setting of insufficient sleep, we create a huge metabolic drive to store fat,” Emsellem said.
In addition to contributing to weight gain, insufficient sleep can also make it more difficult for the body to recoverfrom injury and illness and might cause you to perform poorly during workouts.
SO WHAT CAN I DO TO MAKE SURE I GET A SUFFICIENT AMOUNT OF QUALITY SLEEP?
The easiest thing anyone can do to make sure their body gets enough rest is to follow the National Sleep Foundation’s newly updated guidelines on the hours of sleep required per age group. For most adults, seven hours is the minimum amount of sleep required to maintain a healthy lifestyle.
Additionally, sticking to a sleep schedule where you wake up and go to sleep during the same two-hour window every day — including the weekends — will help your body stay on track.
“If there’s a reproducible schedule, your brain actually determines when you’re going to get sleepy at night based on when you wake up in the morning,” Emsellem said. “So particularly for people in school, or for people taking classes at night after work, having a regular and a regimented wake up time becomes pretty important.”
Emsellem also recommends avoiding light-emitting devices like cellphones, iPads, and televisions around bedtime.
“Our very primitive, caveman brain uses dark as the cue to go to bed, and light is the cue to wake up, and we have not figured out how to turn that wiring off yet,” Emsellem said.
Besides staying away from light-emitting gadgets, Emsellem suggests prepping for bedtime by winding down with a warm bath or gentle yoga. Also, if pure silence is hard for you to fall asleep to, she suggests listening to a short 20-minute playlist or a podcast on an old-school mp3 player that doesn’t emit light.
Personally, I enjoy turning on a white noise machine at night, as the consistent sound helps me block out any other noises that might inhibit my sleep. I like the Marpac Dohm White Noise Sound Machine — it’s had me sleeping like a baby for almost a year now.