What vitamin deficiency is associated with blurred vision?

From the Guidelines

Vitamin A deficiency is the primary vitamin deficiency associated with blurry vision, and adults experiencing such symptoms should consider oral supplementation with 10,000-25,000 IU of vitamin A daily for 1-2 weeks for clinical improvement, as recommended by the British Obesity and Metabolic Surgery Society guidelines 1.

Key Considerations

• Vitamin A plays a crucial role in maintaining the health of the retina and cornea, and its deficiency can lead to night blindness, dry eyes, and more severe vision problems.
• Good dietary sources of vitamin A include liver, sweet potatoes, carrots, spinach, and dairy products.
• Other vitamins that can affect vision include vitamin B1 (thiamine), B12, and E deficiencies, which may also contribute to vision problems through different mechanisms.

Treatment and Prevention

• For adults, oral supplementation with 10,000-25,000 IU of vitamin A daily for 1-2 weeks is recommended for clinical improvement 1.
• If vitamin A deficiency does not respond to treatment, referral to a specialist for assessment and consideration of intramuscular vitamin A injections may be necessary 1.
• Pregnant women or those planning to conceive should restrict their vitamin A intake to 5,000-10,000 IU/d to avoid hypervitaminosis A and potential teratogenic risks 1.

Important Notes

• If blurry vision persists despite dietary changes, it is essential to consult an eye care professional promptly, as it could indicate other serious conditions requiring medical attention.
• Vitamin A deficiency can be particularly problematic for bariatric patients due to limited absorption area, fat malabsorption, and bacterial overgrowth, making regular monitoring and supplementation crucial 1.

From the Research

Vitamin Deficiency and Blurry Vision

• Vitamin A deficiency is a major cause of blindness in children worldwide, and it can also cause blurry vision 2.
• Lutein and zeaxanthin are carotenoids that can help prevent age-related macular degeneration (AMD) and cataracts, which can cause blurry vision 3, 4, 5, 6.
• A diet rich in dark leafy vegetables and fruits can help prevent vitamin deficiencies and reduce the risk of blurry vision 3.
• The Age-Related Eye Disease Study (AREDS) formulation, which includes antioxidants and zinc, has been shown to reduce the risk of progression to advanced AMD 5, 6.
• Adding lutein + zeaxanthin, DHA + EPA, or both to the AREDS formulation may not further reduce the risk of progression to advanced AMD, but lutein + zeaxanthin could be an appropriate carotenoid substitute in the AREDS formulation 6.

Specific Vitamins and Blurry Vision

• Vitamin A deficiency can cause xerophthalmia, which can lead to blurry vision and even blindness 2.
• Lutein and zeaxanthin can help protect the eyes against oxidative stress and reduce the risk of AMD and cataracts 3, 4, 5, 6.
• Omega-3 fatty acids, particularly DHA, have been found to improve dry eye syndrome (DES) and reduce the risk of AMD 4, 5, 6.

Prevention and Treatment

• A balanced diet rich in fruits, vegetables, and whole grains can help prevent vitamin deficiencies and reduce the risk of blurry vision 3, 4.
• Nutritional supplements, such as the AREDS formulation, may be recommended for individuals at risk of AMD or cataracts 5, 6.
• Regular eye exams and early treatment can help prevent or slow down the progression of eye diseases that can cause blurry vision 2, 4, 5, 6.