What are the Main Causes of Night Blindness?

What is Night Blindness (Nyctalopia)?

Night blindness, or nyctalopia, is poor vision at night or in dim lighting, like in a movie theater. It occurs when the eye can’t adapt to dim light from a brightly lit environment. Night blindness differs from complete blindness because daytime vision isn’t affected. 

True night blindness is not the same as having an eye disease that causes poor night vision. Examples include:

• Cataracts
• Myopia
• Glaucoma

Night blindness isn’t a disease but a symptom of an underlying condition. Treatment depends on identifying and addressing the root cause. It’s crucial to see an eye doctor for a comprehensive eye exam if you experience night blindness.

Symptoms of Night Blindness 

Because night blindness is a symptom of an underlying eye problem, symptoms vary depending on the cause.

The most common signs and symptoms of night blindness include:

• Loss of night vision
• Blurry vision in low light
• Halos or glare around lights
• Light sensitivity
• Trouble seeing distant objects in low-light conditions
• Total vision loss when entering a dark room
• Difficulty seeing faces in a poorly illuminated environment
• Inability to see stars in the night sky
• Difficulty driving at night

What is the Main Cause of Night Blindness?

Many different eye conditions can lead to night vision problems. The most common causes of night blindness are:

Myopia (Nearsightedness)

This common refractive error causes blurred vision when looking at distant objects. People with severe myopia may have impaired night vision.

Glaucoma

This eye condition damages the optic nerve, which connects the retina to the brain. 

Glaucoma medication causes the pupil to constrict, which prevents enough light from entering the eye. This can make people with glaucoma experience poor night vision.

Cataracts

A cataract is the clouding of the normally clear lens of the eye. It causes everything to appear blurry or hazy. Poor lighting can worsen these symptoms.

Vitamin A Deficiency

Vitamin A is essential for good eye health. Night blindness is an early sign of vitamin A deficiency.  

Diabetes

Uncontrolled blood glucose levels can damage the blood vessels in the eyes and lead to diabetic retinopathy. Poor night vision is one of the first symptoms of diabetic retinopathy. 

Genetic Conditions

Night blindness can be a symptom of a genetic condition affecting the retina. These include:

• Retinitis pigmentosa
• Usher syndrome
• Choroideremia

How Does Night Vision Work?

To see in the dark, your eyes must adjust properly. This starts with your pupils. 

When you move from a well-lit area to dim lighting, your pupils become larger (dilated). This allows more light to enter your eye and reach your retina.

The retina is a layer of light-sensitive tissue at the back of the eye. It contains specialized cells called rods and cones (photoreceptors). Rod cells are extremely light-sensitive, enabling you to see in dark conditions.

Problems with night vision can occur if the rod cells in the retina stop working. This can result from acquired or inherited eye diseases or injuries.  

How is Night Blindness Treated?

Because night blindness is due to an underlying condition, treatment will depend on the cause. 

Your eye doctor will review your medical history and perform a comprehensive exam to diagnose your condition. They might run special tests to confirm a diagnosis. Then, they will recommend the best treatment for your needs. 

Treatment may be as simple as wearing corrective lenses, such as glasses or contact lenses, or switching glaucoma medications. Some conditions, such as cataracts, require surgery. 

People with a retinal disease should consult a retina specialist to determine if treatment or care support is possible. 

How Can I Cure Night Blindness Naturally?

Night blindness is not treatable at home. Instead, consult an optometrist and seek medical advice for proper treatment. 

Steps can be taken to help prevent night blindness, including: 

Eating Vitamin A-Rich Foods

Foods high in vitamin A include:

• Eggs
• Leafy green vegetables like spinach
• Orange and yellow fruits and vegetables like cantaloupe, sweet potatoes, and carrots
• Cod liver oil
• Fortified milk and cereals

Vitamin A supplements may be helpful, but it is best to speak with a healthcare provider first. 

Scheduling Regular Eye Exams

An eye care specialist can identify early-stage eye problems and provide the most appropriate treatment plan. 

Wearing Sunglasses

UV exposure raises the risk of cataracts, macular degeneration, and glaucoma. These eye problems could impact vision and lead to night blindness. 

Exercising

Working out could reduce eye pressure and lower blood glucose. This helps minimize the risk of further eye problems.

Summary

Night blindness is when you have trouble seeing clearly at night or in dimmed lighting. This condition usually indicates an underlying problem. 

Consult an eye doctor to determine the proper treatment. Different preventative steps are also available to minimize the progression and risk of night blindness.