Hormones are chemicals in your body that control activities throughout your body. Often called the body’s “messengers,” hormones travel through your bloodstream and other fluids to organs and tissues, telling the body’s cells what to do and when to do it. Hunger, behavior, sleep, reproduction and mood are just a few of the body’s major functions that hormones coordinate and control. Everyone experiences hormonal changes throughout their lives, and these changes affect all parts of your body, including your eyes.
Hormones and Children’s Vision
Children’s bodies grow and change quickly during puberty, when hormones are surging. As their arms and legs grow longer, so do their eyeballs. This lengthening of the eyeball can cause blurry vision from myopia (nearsightedness).
“Once a teenager’s hormones stabilize, vision should become more stable as well,” explains Stephen Lipsky, MD, a pediatric ophthalmologist in Atlanta, Georgia. “But it's important to have annual eye exams during and after puberty to make sure your child has the best vision possible.”
Women and Hormonal Vision Changes
Thanks to hormones, women may experience vision changes throughout their adult lives. The hormones estrogen and progesterone have a lot to do with this. Their changing levels can affect the eye’s oil glands, which can lead to dryness. Estrogen can also make the cornea less stiff with more elasticity, which can affect how light travels into the eye. The dryness and the change in refraction can cause blurry vision and can also make wearing contact lenses difficult.
“With the hormonal influence of birth control pills, pregnancy, and menopause, women can deal with a lifetime of fluctuating vision,” says Elena Jimenez, MD, a comprehensive ophthalmologist in Puerto Rico. “We may have some blurry vision or irritated, uncomfortably dry eyes. Often, lubricating eye drops can help with the dryness associated with hormonal changes.”
Fortunately, blurry vision due to hormonal changes often resolves when hormones level out. However, if your vision doesn’t return to normal a couple of months after pregnancy, or it suddenly changes or becomes very blurry, it is very important to see your ophthalmologist right away to rule out more serious medical eye conditions like diabetes.
Thyroid Hormones and Vision
Thyroid hormones play a crucial role during the body’s development, including development of the eyes.
Thyroid eye disease develops when the body’s thyroid gland does not produce the correct amount or type of hormones. One condition, called Graves’ disease, develops when an antibody (a blood protein) attacks the thyroid gland, often leading to over- or under-production of thyroid hormone. This same antibody can attack tissues around the eye. Symptoms include bulging eyes. However, while the same antibody attacks the thyroid gland and the eye, the resulting thyroid problems and eye problems are two separate issues. Thyroid eye disease can occur even when someone’s thyroid gland functions normally.
Abnormal thyroid hormone levels can impact other aspects of eye development and disease.
Research has shown that people with higher levels of a certain thyroid hormone (T4) are at increased risk of having age-related macular degeneration (AMD) and other retinal changes. And in another study, thyroid hormone levels appear to affect the ongoing development and regulation of the eye’s cones (cells responsible for your color vision).
When Should You See a Doctor About Your Vision Changes?
It is normal to have vision changes as we age. However, here are some changes that signal a possible problem with your eyes:
• Bulging of one or both eyes;
• Dark curtain or veil that blocks your vision;
• Decreased vision, even if temporary;
• Distorted vision;
• Double vision;
• Excess watering/tearing;
• Halos (colored circles around lights);
• Loss of peripheral (side) vision;
• New floaters (black "strings" or specks in the vision) and/or flashes of light;
• Pain in the eye;
• Unusual red eye.
If you have any of these symptoms, or you feel your vision changes happen suddenly, see an ophthalmologist right away. Your ophthalmologist may ask you to visit your medical doctor to find out if out-of-balance hormones are a factor in your vision changes.