Are Your Eyes Getting Enough Vitamin D?
Vitamin D is essential for healthy vision, yet many of us don't get enough of this important vitamin. Luckily, increasing your intake of vitamin D is fairly simple.
Why Is Vitamin D So Important?
Most Americans don't get enough vitamin D in their diets. In fact, 28.9% of U.S. adults were considered deficient in vitamin D, while another 41.4% received insufficient amounts of the vitamin, according to the National Health and Nutrition Examination Survey.
Vitamin D helps your bones absorb calcium, bolsters your immune system, keeps your muscles strong, and prevents some types of cancer. Good lung, brain and heart health depend on this crucial nutrient.
Vitamin D may also play a part in these eye conditions and diseases:
- Dry Eye. Do your eyes ever feel dry and itchy? Those symptoms, in addition to redness, burning, tearing and sensitivity to light, may mean you have dry eye.
- Glaucoma. High pressure inside your eye causes glaucoma, which may damage the optic nerve. The nerve sends electrical impulses from the eye to the brain. If any part of the optic nerve is damaged due to glaucoma, you'll suffer permanent vision loss. Fortunately, it may be possible to prevent or reduce vision damage if glaucoma is detected early.
- Macular Degeneration. Macular degeneration affects the center of the retina, the light-sensing tissue at the back of the eye. The disease causes blurry central vision or a blank spot in your central vision. Macular degeneration is often referred to as "age-related" macular degeneration (AMD) since it usually affects older people.
- Cataracts. Cataracts dull your vision, cause haloes around lights and make it difficult to handle glare. These problems happen when the clear lens inside your eye becomes cloudy. The lens, a curved structure located behind your iris and pupil, changes shape to help you see clearly whether you're looking at a near or far object.
- Diabetic Retinopathy. Diabetic retinopathy causes vision loss when blood sugar is consistently high in people who have diabetes. Blood vessels in the retina leak blood or fluid, obstructing vision. New, abnormal blood vessels may form and begin to leak. In some cases, scar tissue also forms, worsening vision.
What Research Tells Us About the Link Between Vitamin D and Eye Health
Researchers have been curious about the effects of vitamin D for some time. Among the most interesting discoveries are:
- Vitamin D Deficiency Might Make the Retina or Macula Thinner. Research participants who were deficient in the vitamin had thinner central macular areas, according to a study published in Cureus in 2021. Researchers also noted thickness differences in the retinal nerve fiber layers when comparing results from patients with severe deficiencies compared to those who were less severe.
- Adequate Vitamin D Levels May Lower the Risk of Age-Related Macular Degeneration. According to a systematic review published in Maturitas, a high 25-hydroxyvitamin D concentration is associated with a reduction in AMD.
- The Link Between Vitamin D and Dry Eye: In another study published in the Indian Journal of Ophthalmology in 2022, researchers discovered that people with vitamin D deficiencies were more likely to have dry eye than those with normal levels of the vitamin.
Although these study results are fascinating and certainly help support the link between low vitamin D and eye disease, researchers note that more research is necessary.
3 Ways to Get Vitamin D
Wondering how you obtain vitamin D? Your level of the nutrient increases through any of these methods:
- Eat Foods that Contain the Vitamin. These include fortified milk and orange juice, soy drinks, egg yolks, salmon, sardines, tuna, and beef liver.
- Take Supplements. Supplements can help you increase your vitamin D intake if the foods you eat don't provide enough vitamin D.
- Spend Time in the Sun. Your body produces vitamin D when you venture outdoors on a sunny day. Unfortunately, most people don't get enough vitamin D through sun exposure alone. Doctors don't recommend that you use low vitamin D as an excuse to sunbathe though, as sun exposure increases your skin cancer risk.
In addition to increasing your vitamin D intake, visiting the optometrist will help you keep your eyes healthy. Need to make an appointment? Give our office a call to schedule your visit.
Sources:
NCBI: The British Journal of Nutrition: Vitamin D Deficiency and Insufficiency Among US adults: Prevalence, Predictors and Clinical Implications, 4/11/2018
https://pubmed.ncbi.nlm.nih.gov/29644951/
NCBI: Cureus: Ocular Findings Among Patients with Vitamin D Deficiency, 5/21/2021
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8215305/
Indian Journal of Ophthalmology: A Study of the Association Between Vitamin D Deficiency and Dry Eye Syndrome (DES) in the Indian Population, 2/2022
Maturitis: Circulating Vitamin D Concentration and Age-Related Macular Degeneration: Systematic Review and Meta Analysis, 6/2016
https://www.maturitas.org/article/S0378-5122(16)30072-X/fulltext
Review of Optometry: Vitamin D Comes to Light, 11/15/2013
https://www.reviewofoptometry.com/article/vitamin-d-comes-to-light-45073