Babies who cry at night rather than sleep can wreak havoc on the health, wellbeing and work performance of their parents, so any natural method of helping the baby to sleep well would be welcomed in most families. One of the best natural methods is to expose the baby to outdoor light, and research showed that infants who slept well were exposed to significantly more early-afternoon light than their counterparts who did not sleep well. We have discussed previously in this blog that circadian rhythms are controlled to a great extent by sun or the lack thereof, and these researchers stated, “These data suggest that light in the normal domestic setting influences the development of the circadian system.” Proper circadian rhythms are also vitally important for adults, and when disrupted predict an increase in illness and death from many maladies, particularly from our number-one killer, cardiovascular disease.
Melatonin, which should exhibit high levels at night, is a sleep inducer, and its production is enhanced when the lights go out at night. But, for that to happen, there must be sufficient bright light earlier in the day.
For babies or adults, here is how the system should work: When we awake to sunshine, light enters the eye and stimulates serotonin production; we then quickly become awake and invigorated, and melatonin is suppressed. At day’s end, however, the bright light disappears (or at least that is how nature intended it), melatonin levels rise, and serotonin levels diminish. We begin to feel sleepy and ideally go to bed for a good night’s rest. It is a perfect system for our needs—that is until we stay up far beyond biologically natural hours by using artificial lighting.
Is there and answer to a disrupted circadian rhythm and poor sleep quality? Yes! A paper entitled Circadian clocks optimally adapt to sun for reliable synchronization has the answer. In it, the authors explain that circadian rhythms are best synchronized by sun. It therefore occurs that to escape the ravages of electric lighting, it would be a good idea to reset our biological clocks daily by being out in the morning sun and at other times, when possible, and to avoid long hours of light exposure at night. This could be one of the best therapies possible when we feel “out of synch.” And, catching some sun throughout the day would also keep serotonin levels higher and keep our moodiness in check. All of us know that we feel better when we are in the sun. This, coupled with enhancement of health, demonstrates that our friend, the sun, is an essential companion for optimal living.
So take care of your babies as nature intends, and also take care of yourself with non-burning daily sun exposure.
 Harrison Y. The relationship between daytime exposure to light and night-time sleep in 6-12-week-old infants. J Sleep Res. 2004 Dec;13(4):345-52.
 Jason Brainard, Merit Gobel, Benjamin Scott, Michael Koeppen and Tobias Eckle. Health implications of disrupted circadian rhythms and the potential for daylight as therapy. Anesthesiology. 2015 May ; 122(5): 1170–1175.
 Hasegawa Y, Arita M. Circadian clocks optimally adapt to sun for reliable synchronization. J R Soc Interface. 2013 Dec 18;11(92):20131018.