How do hormones affect vision?

Hormones play a vital role in many of the activities that our body carries out on a daily basis. Acting as messengers, they help with metabolism, growth, and even the way we see. Yes, hormones affect our eyes and vision. Depending on the hormone(s) involved, your gender, and age, the effects on your vision can vary.

Which hormones affect our vision?

Here are some of the main hormones that affect our vision:

• Gonadotropin-releasing hormone (GnRH)
• Estrogen
• Progesterone
• Testosterone
• Thyroid hormones: triiodothyronine (T₃) and tetraiodothyronine (T₄)
• Insulin

Different life stages and vision changes

Other than refractive errors, such as myopia (nearsightedness) or hyperopia (farsightedness), changes to our vision can occur for other reasons, such as hormonal changes. These can occur naturally, due to age, like in menopause, or they can happen because of disease, such as in diabetes.

• Adolescence: GnRH travels to the pituitary gland to signal the release of other hormones to begin puberty. Growth spurts during this time can temporarily lengthen the eyeball, causing myopia, or nearsightedness, in both boys and girls.
• Pregnancy: fluctuations in estrogen and progesterone can cause changes to the glands in the eyes and eyelids, causing dry, irritated eyes. An increase in estrogen can also affect the shape of the cornea, causing temporary vision changes that are typically reversed after pregnancy.
• Menopause: a decrease in estrogen can cause the structures of the eye to become dry and less elastic, causing dry eye and blurry vision. Menopausal women also tend to have higher intraocular pressure which, if left untreated, could lead to glaucoma.
• Middle-age for men: as testosterone levels naturally drop with age, men may experience dry eyes and blurry vision, in the same way menopausal women do. This is due to changes in the tear ducts and the oily film in the eyes that keeps them moist.
• At any age: people who experience excessively high or low thyroid hormones can experience changes to their vision. For example, high levels of the T₄ hormone can increase the risk of age-related macular degeneration. The thyroid hormones also contribute to the development of cones, the cells in our eyes responsible for colour vision. Furthermore, for people with diabetes: low levels of insulin can make it difficult for your eyes to produce tears, causing dry eyes. This can affect people with both type 1 and type 2 diabetes.

If you experience any sudden changes in vision, especially flashes of light or a dark “curtain” descending over your field of vision, it’s important to see an eye doctor right away.

LASIK candidacy and vision changes

The best way to determine if you’re a candidate for LASIK, or another laser vision correction procedure, is to book a free consultation with us. If your vision has been stable for some time, you can likely get LASIK. However, some vision changes from hormones will require that you wait, like during pregnancy.