03 Nov Daylight Savings: Exactly What Are We Saving?
Neither falling back nor springing ahead counts as exercise and what’s worse, all this toggling between times can impact your health and your weight.
Unless you live in Arizona or Hawaii, this weekend Americans turn our clocks back to standard time. Here in Washington (the state), lawmakers have voted to keep our clocks set at Daylight Savings Time. I am a HUGE fan of getting rid of the bi-annual switch between times, but not so keen on keeping the clock on Daylight Savings Time.
We are wired to respond to environmental cues, including light and dark.
You’ve probably heard of the term “circadian rhythm.” It’s not a new style of dance, rather it’s the 24 hour cycle of physiologic processes expressed in pretty much all living beings from cyanobacteria to plants to human beings. So that the significance of this isn’t lost, here’s what I mean by “physiologic processes”:
- Brain wave activity
- Hormone production
- Cell regeneration
- Wake and sleep cycles
Hormones Rule the World
There’s a small glad in the brain called the pineal gland that is the commander of circadian rhythms. Though the pineal gland isn’t completely understood, we do know it produces melatonin. You may be aware that melatonin is important for sleep regulation and adequate, restful sleep is associated with weight management.
Greater exposure to sunlight is associated with a release of the feel-good hormone serotonin. Serotonin is the precursor of melatonin. Connecting the dots, it looks like this:
Morning sunlight means more serotonin, which supports calm, happy mood during the day.
More serotonin translates to more raw material to make melatonin, which translates to better quality sleep at night and the host of health benefits that come with getting enough sleep.
Morning light signals the brain that it’s time to stop melatonin production and increases cortisol production. Cortisol has been getting some bad press lately because of its role as a stress hormone. It’s true that a constant flow of cortisol leads to poor health outcomes, including abdominal weight gain. But cortisol plays an important role in our circadian rhythms. Cortisol is supposed to spike in the morning, giving you a boost of energy to start the day. It then tapers off, which is necessary to fall asleep at night, when melatonin should be back on the rise.
The Short Story
Morning light signals melatonin (sleepy hormone) to turn off and cortisol (go get ’em hormone) to turn on. When the sun goes down, melatonin rises and cortisol should be at its low point, inducing sleep.
When we play this Daylight Savings Time game, we push sunlight hours to the evening. We don’t gain any hours, we just rob ourselves of the morning sunlight that drives important hormonal pathways.
Not only does this impact our health (including weight and mood), it impacts our performance at work, at school, and behind the wheel of a car.
So, let’s get rid of the time change, but make sure we lock it in at Standard Time in the best interest of public health and well-being.