Carrots are rich in beta carotene --- the plant form of vitamin A, which is critical to eye health. Vitamin A's primary ocular benefit is to the outer surface of the eye, but it also helps to boost the immune system. This helps control inflammation, one contributing factor to elevated eye pressure. If you have chronic high eye pressure, see an eye doctor to get your pressure checked regularly. Early intervention can help to prevent irreversible damage to your optic nerve.
Definition
Your eye contains two fluids --- a gel-like substance called vitreous humor that fills the posterior portion your eyeball and gives it its shape, and a thinner liquid called aqueous humor that occupies the much smaller front chamber of your eye. The combined force of these two fluids pressing on your eyeball from the inside is your intraocular pressure, informally called eye pressure. The amount of vitreous humor in your eye remains constant throughout your life, but your body continually produces and drains aqueous humor, which provides nourishment to the delicate structures inside your eye, including the lens and the muscles that bend it. Normal eye pressure is between 10 and 20 mmHg. It varies throughout the day, depending on your level of activity, and tends to be lowest in the early morning.
Elevated Eye Pressure
Sustained high eye pressure usually is the result of a problem in the eye's drainage system. In some cases, the problem is structural. For example, damage to the eye tissues from inflammation may cause a narrowing of the drainage canal. Often, the problem is a build-up of debris that clogs the trabecular meshwork, which filters aqueous humor as it drains from your eye. High intraocular pressure causes damage to your optic nerve and may lead to glaucoma, which causes a loss of peripheral vision and, eventually, blindness. Eating carrots does not clear debris from the meshwork inside your eyes, but it can help with inflammation and structural problems that contribute to abnormally high eye pressure.
Eye Health
Carrots contain beta carotene, which your body converts into Vitamin A. This vitamin is an important antioxidant that helps to support your immune system and the tissues of the tiny structures within your eyes. A healthy immune system can help to fight viruses and diseases that cause inflammation and associated structural damage that increase eye pressure. A study conducted by a research team led by Anne L. Coleman and reported in the February 2008 edition of the "American Journal of Ophthalmology" found that women who consumed two or more servings of carrots per week were 64 percent less likely to suffer from glaucoma than women who consumed one or fewer servings per week.
Amount
The Institute of Medicine recommends a minimum 3,000 IU of vitamin A daily for adult males and 2,310 IU for adult females. Children between the ages of 9 and 13 need 2,000 IU daily and younger children, ages 4 through 8 need only 1,380 IU. Toddlers between the ages of 1 and 3 need only 1,000 IU daily. Consuming very small amounts of carrots will enable you to reach this goal. For example, a single raw carrot contains 8,666 IU of the beta carotene form of vitamin A and 1/2 cup of boiled carrots provides 13,418 IU. If you prefer carrot juice, 1/2 cup will provide 22,567 IU of beta carotene. Although too much vitamin A can be detrimental to your health, the beta carotene found in carrots is safe because your body simply stops converting it into vitamin A when you have reached sufficient levels.
References
- Open Optix: ABO Study Guide; Version 1.3; July 2009
- MayoClinic.com: Glaucoma; July 2010
- Glaucoma-Eye-Info.com: What Is Intraocular Pressure?
- "American Journal of Opthalmology"; Glaucoma Risk and the Consumption of Fruits and Vegetables Among Older Women in the Study of Osteoporotic Fractures; Anne L. Coleman et al; January 2008
- Office of Dietary Supplements: Vitamin A and Carotenoids; April 2006
- Institute of Medicine: Dietary Reference Intakes for Vitamins; January 2001
