This article was written by Lindsea Willon, MS, NTP
“We recently talked about the relationship of sleep to cortisol. So now, let’s discuss the “sleep hormone” melatonin, which is especially a hot topic amongst night owls, shift workers and jet setters because of its reputation for promoting sleep. In fact, most people have only heard of melatonin in relation to sleep but actually the changing levels of melatonin in the body help regulate functions related to light and dark cycles like metabolism, immunity and reproduction. Therefore, we want to clear up the misconceptions, as well as explain its powerful role.
First, melatonin is produced by the brain during sleep. It does NOT cause sleep and is only secreted when there is darkness. In fact, levels of this hormone peak in the middle of the night and decrease rapidly when a person is exposed to light.
For our ancestors, this process began when the sun went down. The sun would set, melatonin was secreted and they went to sleep, and actually, daylight was the only thing that would depress melatonin secretion. As a result, and because its production preceded sleep, it makes sense why someone today would have the misconception that it is necessary to take melatonin before bed. But the truth is that melatonin cannot be produced in the presence of light, even artificial light.
In today’s society, darkness has nothing to do with the sun. When the sun sets, we turn on the lights, watch television, take our phones and computers to bed and then go to sleep. Closing our eyes is really the first time our brain registers full darkness because the artificial light that is used is just as effective at suppressing melatonin as the sun. In fact, the most egregious artificial light and melatonin suppressor is blue light, which comes from electronic screens. Therefore, modern day melatonin production actually follows sleep. It does not cause it!
So, how does the importance of melatonin affect you?
With the younger generation staying up later and having phones and electronics at earlier ages, this artificial and blue light is causing early sexual development. Even though this is also blamed on synthetic hormones in our food supply, it is important to take note of the prolonged period of suppressed melatonin that naturally precedes puberty. It is critical to not mimic this phenomenon by artificially and repetitively lowering melatonin on our kids with the over-exposure to indoor light. Therefore, implementing a limited screen time and an early bedtime for children is crucial for a healthy puberty.
Melatonin also affects adult sexual function by suppressing sex hormone production. Remember, melatonin production occurs when a person closes their eyes, but it also helps to ensure that it’s time for sleep, nothing else. When we also look at our seasonal breeder biology, melatonin is lowest in the summer when nights are short. This helps to assure that sexual function is at its peak nine months before spring, which is historically the most advantageous time to have a baby. And while natural melatonin in the proper rhythm is beneficial, supplementation can be detrimental to sexual function. So, considering melatonin is recommended 30 minutes before bedtime, it might as well be the anti-“little blue pill.”
After understanding some of the misconceptions and learning about some of the detrimental effects, we are sure that melatonin supplements are much lower on your “to try” list. However, if it is still on your sleepless mind or nightstand, remember that melatonin does not cause sleep and no amount of supplemental melatonin will counteract the brightness of artificial and blue light. In fact, while melatonin is a beneficial hormone crucial for regulating multiple systems in our body, the resulting supplementation will do more harm than good.
So, for those who still struggle with sleep, stayed tuned for next month’s post, the last in our Sleep Series. We will focus on safe and natural alternatives to this misunderstood “sleep hormone” and give recommendations on what to do to support healthy sleep. For now, go to bed early, turn off the lights, put away the computers and cell phones, don’t reach for the melatonin supplement and make sure your kids do the same.