Iron deficiency, also known as anemia, is a common condition that occurs when the body does not have enough of the mineral iron. Iron is an essential nutrient that is needed to produce hemoglobin, a protein in red blood cells that transports oxygen throughout the body. When iron levels are low, the body cannot produce enough hemoglobin, resulting in a reduced ability for blood cells to carry oxygen. This can lead to a variety of symptoms, including changes in the eyes.
What are the most common eye symptoms of low iron?
Some of the most common eye symptoms associated with iron deficiency anemia include:
- Dry eyes
- Eye twitching
- Light sensitivity
- Blurred vision
- Double vision
- Strange sensations in the eyes
- Swelling or redness of the eyelids
Many of these symptoms occur because iron deficiency can reduce blood flow to the optic nerve and disrupt nerve signals between the eye and brain. The lack of iron leads to reduced oxygen supply to eye tissues, which can cause abnormal functioning.
Why does low iron cause dry eyes?
Dry eyes are a very common symptom of iron deficiency anemia. This occurs for a few reasons:
- Iron helps stimulate tear production. When iron is low, tear gland function may decline.
- Anemia can reduce blood flow to tear glands, limiting their ability to produce tears.
- Iron plays a role in mucin production. Mucin is a component of tears that helps keep the eyes lubricated. Without enough iron, mucin production may decrease.
- Inflammation caused by anemia can disrupt tear film stability and lead to increased tear evaporation.
The reduced tears means the eyes are not getting lubricated properly. This causes dryness, irritation, burning or stinging of the eyes. Using artificial tear drops can help provide temporary relief.
Why does iron deficiency cause eye twitching?
Involuntary eye twitching or spasms of the eyelid are common when iron is low. This can occur for several reasons:
- Iron is needed for muscular contractions. Anemia can disrupt signals between nerves and eye muscles, leading to uncontrolled twitching.
- Lack of oxygen from anemia causes eye muscle fatigue. This can trigger spasms as the muscles try to compensate.
- Anemia leads to inflammation that may irritate nerves and muscles around the eyes.
- Stress and anxiety from anemia symptoms can trigger eye twitching.
Eye twitches caused by anemia are usually temporary and disappear once iron levels are restored. Using an eye patch, staying hydrated, and reducing stress can help manage this symptom.
Why does low iron make eyes sensitive to light?
Photophobia or light sensitivity is a common visual disturbance with iron deficiency anemia. Reasons this occurs include:
- Inflammation caused by anemia can make the eyes more sensitive to sunlight, artificial lights and glare.
- Iron is needed to produce melanin pigment that protects the eyes from excessive light exposure. Anemia reduces melanin levels.
- Low iron disrupts signals between light-sensing nerves in the retina and the brain that control pupil size. This makes it harder for the eyes to adjust to different light conditions.
Wearing sunglasses, brimmed hats or transition lenses can help reduce light sensitivity from anemia until iron levels are restored.
Why do you get blurred vision with low iron?
Blurred vision or difficulty focusing with iron deficiency occurs due to:
- Changes to the cornea and lens shape from anemia that disrupt how light is refracted to the retina.
- Inflammation and dry eyes that distort the visual image.
- Reduced blood and oxygen supply to eye muscles, making it harder for the eyes to focus properly.
- Disruption of retina and optic nerve signals that affect visual processing in the brain.
This blurred vision tends to come and go. Using reading glasses, taking frequent breaks when using the eyes, and keeping hydrated may help reduce blurry episodes until anemia is treated.
Why do you get double vision with low iron?
Some individuals with iron deficiency anemia experience diplopia, or double vision. Potential mechanisms include:
- Imbalances in eye muscle coordination and control due to reduced oxygenation, causing the eyes to become misaligned.
- Inflammation or fatigue of the cranial nerves that control eye movements.
- Impaired transmission of images from each eye to the brain, preventing proper fusion of the two visual fields.
- Swelling of the optic nerve or retinal hemorrhages resulting in two overlapping visual images.
Double vision from anemia often resolves once iron levels improve. Prism eyeglasses may help realign the visual axes in severe cases.
What kind of strange eye sensations can occur?
Some individuals with iron deficiency report unusual eye sensations or perceptions, such as:
- Seeing random flashes of light
- Seeing strange shapes, colors or geometric patterns
- Having a burning, crawling or watery sensation in the eyes
- Tunnel vision
- Having difficulty coordinating eye movements
These visual disturbances are likely caused by inflammation, fatigue and abnormal signaling between the eyes and brain due to anemia. They tend to resolve once the anemia is treated and iron levels improve.
Why do your eyelids swell with low iron?
Swollen or reddened eyelids can sometimes occur with iron deficiency. This is generally caused by:
- Fluid retention and mild inflammation associated with anemia that causes puffiness around the eyes.
- Allergic reactions to anemia-related changes in eye tissues.
- Rubbing or irritation of the eyelids from dry eyes or photophobia.
- Bleeding in the eyelids from fragile blood vessels (rare).
Applying cool compresses can provide relief from swollen eyelids until iron levels are restored. Severe swelling may require medical treatment.
How are eye symptoms diagnosed as being from low iron?
Eye symptoms alone may have many causes, so iron deficiency anemia must be confirmed through diagnostic blood tests for a diagnosis. These may include:
- Complete blood count (CBC) to check hemoglobin and hematocrit levels
- Iron level blood test
- Ferritin blood test to measure stored iron
- Total iron binding capacity test
A detailed eye exam can check for direct signs of anemia like pale conjunctivae, retinal hemorrhages or optic disc swelling. Your doctor may also evaluate for other potential causes of your eye symptoms.
What is the treatment for low iron eye symptoms?
The main treatment for eye problems from iron deficiency anemia is to increase iron intake, usually with oral iron supplements. This helps restore normal hemoglobin production and oxygen delivery to eye tissues.
Some additional treatments that may help manage eye symptoms include:
- Over-the-counter artificial tear drops for dry eyes
- Wraparound glasses or sunglasses for light sensitivity
- Eye patches or prisms for double vision
- Resting the eyes when fatigued
- Ensuring adequate hydration
For severe swelling or hemorrhage, surgery or injections may be needed. But in most cases, the eye symptoms resolve once the anemia is successfully treated with iron supplementation.
Can low iron cause permanent eye damage?
In most cases, the eye symptoms and visual disturbances from iron deficiency anemia are temporary and reversible with proper treatment. However, some potential risks if anemia is left untreated include:
- Chronic dry eye leading to corneal abrasions or ulcers
- Retinal damage from bleeding
- Cataracts
- Optic nerve atrophy
- Glaucoma
Significant or long-standing iron deficiency has been associated with higher risks of certain eye diseases. However, early detection and iron supplementation can prevent permanent eye damage in the vast majority of patients.
When should you see a doctor?
You should see a doctor promptly if you experience any new onset eye symptoms potentially associated with iron deficiency anemia, including:
- Blurry vision
- Double vision
- Dry eyes
- Swollen eyelids
- Light sensitivity
- Eye twitching
- Flashing lights or floaters
It’s important to identify or rule out iron deficiency anemia as the cause. Timely detection and treatment can resolve symptoms and prevent complications. Persistent or concerning eye issues should always be evaluated by an optometrist or ophthalmologist.
Who is most at risk for low iron eye problems?
Those at highest risk for developing eye symptoms related to iron deficiency anemia include:
- Women of childbearing age due to blood loss from menstruation
- Young children and teens with increased iron needs for growth
- Pregnant women
- Vegans, vegetarians, or those with poor dietary iron intake
- Individuals with chronic medical conditions that impair iron absorption like celiac disease
- People with heavy menstrual bleeding or ulcers that cause iron loss
Routine screening through a complete blood count test can help detect iron deficiency in at-risk populations and prevent complications like eye issues.
Can you prevent low iron eye problems?
Some ways to help prevent iron deficiency anemia and associated eye symptoms include:
- Eating iron-rich foods like red meat, seafood, nuts, beans, and leafy greens
- Consuming foods high in vitamin C to improve iron absorption
- Taking a prenatal vitamin with iron during pregnancy
- Treating underlying gastrointestinal conditions that reduce iron absorption
- Donating blood no more than twice yearly for men and postmenopausal women
- Having routine CBC testing to monitor iron levels if at high risk
Getting adequate iron intake and monitoring levels can reduce the likelihood of developing anemia and experiencing eye complications.
Takeaway points
- Iron deficiency anemia can cause many eye symptoms like dryness, light sensitivity, double vision, swelling and strange visual perceptions.
- These occur due to insufficient oxygen, inflammation, and impaired nerve signals between the eyes and brain.
- Eye symptoms may be the only noticeable manifestation of anemia and usually resolve with iron supplementation.
- It’s important to get evaluated promptly for iron deficiency if new eye problems develop.
- Early detection and treatment helps reverse symptoms and prevent permanent eye damage from anemia.