Glaucoma is one of the leading causes of blindness in the world and many people who have it don’t even know it.

Because the damage happens slowly, people often notice the problem only after significant vision loss has already occurred.

Yesterday was World Glaucoma Day, a reminder of the importance of protecting our eyesight.

Here are five important things everyone should know about glaucoma:

1) Glaucoma damages the optic nerve

Glaucoma refers to a group of eye conditions that damage the optic nerve, the nerve responsible for vision.

2) Vision loss is often gradual

Many people do not notice symptoms until the disease is already advanced.

3) High pressure inside the eye is a common cause

Fluid normally flows in and out of the eye. When drainage is blocked, pressure builds up and damages the optic nerve.

4) Some people are at higher risk

Risk factors include:

Family history of glaucoma

People over 60 years of age

People of African descent over 40 years

Certain medical conditions such as hypertension

5) Early detection can protect vision

Glaucoma cannot be cured and damage to the optic nerve cannot be reversed. However, early treatment can slow or prevent further vision loss.

Bonus tips:

Treatment may include eye drops, medication or surgery.

The best protection is regular eye examinations, especially if you are in a higher-risk group. Eating healthy is also helpful as you stock up on vitamins that are beneficial for sight. Exercising and reducing caffeine intake may also help.