If you have teenage kids, you know that hormones affect both physiology and
behavior. They can also affect our vision in several ways at those times in our lives when hormonal activity is high.
Adolescence is, of course, prime time for hormonal activity. It’s the time when arms and legs are growing, and so are eyeballs, which can cause blurry vision and contribute to the development or progression of myopia.
For women, hormonal changes throughout adult life can affect vision, particularly during pregnancy and menopause, or while taking birth control pills. Changes in estrogen and progesterone levels can cause dryness, leading to blurry vision and dryness. Estrogen can also make the cornea less stiff, which along with dryness can change the way the eye refracts light and make it difficult to wear contact lenses. Middle-aged men and men with low testosterone may also experience and decline in visual activity.
Conversely, the eyes can also affect hormone production. The recently-discovered intrinsically photosensitive retinal ganglion cells (ipRGCs) are believed to signal the brain to stop producing melatonin, the hormone that helps regulate our sleep cycle. These sensors are stimulated by blue light in roughly the range of 460-485nm. Because digital screens emit significant quantities of light in this range, it is generally believed that prolonged use of digital devices at night can delay sleep. Vision and hormone levels are both moving targets throughout our lives. This fact gives us yet another reason to encourage patients to have annual eye exams.