Sunlight is on my mind this week since Southern California has been overcast and massive snow has fallen on the eastern United States. Sunlight gives us so many things, like vitamin D (which is what the sun’s UV rays help our bodies make which is important for our bones, blood cells, and immune systems). WebMD also says that morning sunlight may help people with weight loss by “shrinking the fat cells below the skin’s surface”.
Sunlight also boosts our seratonin levels which can give you more energy and help you feel calm and happy and focused. And as Richard Weller says in the video below, sunshine may be healthy for your heart.
And sunlight is used to treat jaundice in newborn babies. Jaundice is a yellowing of the skin that happens when too much of the chemical bilirubin is in the blood.
Maybe you knew all of these healthy benefits of sunlight, but did you know it is essential for eye health, especially in children?
Sunlight and Children’s Eye Health
Have you asked yourself if spending time outdoors really matter? According to a slew of studies it does, especially to the health of children’s eyes. Ophthalmologists and eye health researchers around the world have been determining why myopia (nearsightedness) rates have skyrocketed, doubling over the last century. And they think the answer lies in exposure to sunlight.
Myopia, according to the National Eye Institute, is a disorder or “refractive error where close objects appear clearly, but distant objects appear blurry.” This is caused when the eye is slightly elongated or the cornea is too steep, making the light rays then focus in front of the retina instead of on it. Myopia appears in school-age children and adolescents because that is when the eye is growing.
Originally, myopia was thought to develop in kids who read too much and whose parents with the disorder. Researchers now realize that reading a lot is not a cause of nearsightedness, but genetics and not spending time in sunlight is.
Dr. Donald Mutti, of The Ohio State University College of Optometry explained, “Brighter visible light outside stimulates the release of dopamine from the retina and that dopamine slows down the growth of the eye.” Dr. Mutti and his colleagues have studied and published widely on how playing sports and spending time outdoors affects children’s eye health. They found that “children who are genetically predisposed to nearsightedness are three times less likely to need glasses if they spend at least 14 hours a week outdoors compared to children who spend less than 5 hours a week outdoors.” UVB rays create vitamin D, which may benefit the eyes, but that theory needs more testing.
Dr. Ian Morgan, of Australian National University and Sun Yat-sen University in China, and his colleagues found in East and Southeast Asia, where children are subject to intensive schooling and get outside for less than an hour per day, the children become very myopic. Dr. Morgan said, recent controlled trials that have introduced a two-hour outside period per day halved the rate of new myopia cases.
Dr. Morgan said, 10,000 lux is necessary to get a protective eye health effect. (Lux is a unit of light measurement or intensity on a surface.) Both Drs. Morgan and Mutti said that even on cloudy days light intensity could be sufficient to get enough lux. And Nature put lux into perspective by stating that even the brightest of offices or classrooms emits only about 500 lux, so staying indoors most of the day will never give eyes enough dopamine stimulation for eye health.
And it is the sunlight exposure and the length of that exposure not the outdoor activity that matters in children’s eye health. One study found reading outside or having a picnic was just as effective for myopia prevention as playing sports.
So encourage your child to take a break from studying or playing videogames or watching TV and go outside and play. The health of his or her eyes depends on it. Just don’t forget the sunscreen and the sunglasses.