10 Common Vision and Eye Myths

Eye Myths

This week’s blog post is written by Dr. Careen Caputo. 

1. Contact lenses can get lost behind the eyeball

Although contact lenses can dislodge while on the eye it is impossible for them to go behind the eyeball.  The conjunctiva of your eye forms a barrier (connecting the inside eyelid to the eyeball) preventing objects from going behind the eye.  However, sometimes a contact lens can fold and get up under the upper lid causing discomfort

2.  Eating vegetables can improve your prescription

While eating vegetables is important to maintain good health for obvious reasons, it does not change the refractive status of your eyes, i.e. nearsightedness, farsightedness, or astigmatism.  This is determined by the shape of your eye and the natural lens system of the eye and its ability to focus images on the retina for the best clarity.

3. Needing glasses means you have a medical issue

As mentioned above, needing glasses is most often associated with having a refractive error or the inability of the eye to focus images on the retina.  If you are farsighted your eyeball is too short or the cornea has too little curvature, not bending the light enough to get it focused on the retina.  Conversely, if you are nearsighted your eyeball is too long or the cornea has excess curvature, causing light to focus in front of the retina.  Like nearsightedness and farsightedness, astigmatism is a refractive error due to an irregular shaped cornea causing light to not focus on a single point.

4. 20 / 20 is the best vision

The term 20/20 vision is a benchmark term to describe normal visual acuity measured at 20 feet.  However, 20/20 is not the best possible eyesight.  Some people have 20/15 vision indicating they see objects at 20 feet that a person with 20/20 can only see at 15 feet.  Similarly, if you have 20/10 vision you see objects at 20 feet that people with 20/20 vision can only see at 10 feet.

5. My eyes will get weaker if I wear the prescribed glasses

Frequently, I explain to patients that glasses can only bend the light to focus images on the retina so they are seen clearly.  Otherwise, the image is out of focus.  Glasses correct refractive error created by the shape of the eye and therefore cannot weaken the eye.

6. Doing eye exercises will delay the need for glasses

Just as wearing glasses will not weaken your eyes, exercises cannot strengthen the eyes to avoid the need for glasses.  Your vision depends on many factors, including the shape of your eye, which eye exercises cannot alter.  Special eye exercises do exist for people with eye conditions such as amblyopia, strabismus or other ocular motor problems to help the eyes work together and is called Vision Therapy.

7. Sitting too close to the TV will damage your vision

As a youngster, I heard my parents say, “Don’t sit too close to the TV or you’ll ruin your eyes”. I’m sure this has been heard by many children throughout the years.  The fact is sitting too close to the TV may cause some eye strain or a headache but it cannot damage your eyes or vision.  Sometimes children who are nearsighted may sit too close just to see the screen clearly.

8. Reading in the dark will weaken your eyesight

Similar to sitting too close to the TV, reading in the dark will also cause eye strain or a headache but does not pose a threat to your vision or weaken your eyes.

9. Staring at a computer screen all day is bad for the eyes

Another good example of an activity that leads to eye strain or tired eyes.  Focusing on a computer screen is not harmful to your eyes. In each case, whether watching TV, reading, or computer screen time, it is a good idea to rest your eyes briefly to lessen eye strain if you are spending several hours doing any task that keeps you focused at a constant distance.

10. Color blindness means you see only black and white

A better term for color blindness is color deficiency.  Some people cannot differentiate between certain colors such as distinguishing between red and green, or blue and yellow but they do see color.