According to the study, consuming high amounts of beta-carotene, vitamins C and E, and zinc was associated with a substantially reduced risk of AMD in elderly patients. However, it is important to note that the high levels of beta-carotene that produced such results were obtained from vitamin and mineral supplements, and it would be very difficult to reach the same level of intake by eating lots of carrots.
Also, there is no evidence that excessive carrot consumption prevents macular degeneration or other diseases affecting vision at any age. Again, consuming excessive beta-carotene may result in carotemia. During World War II, the British Royal Air Force invented the myth tying carrots to clear, sharp vision as a way to explain the sudden increase in Nazi bombers being shot down.
A disinformation campaign spread the rumor that British fighter pilots were eating carrots to improve their vision, when in reality the British had a new radar system they wanted to keep secret from Germany.
The story caught on though, and it remains popular to this day. Although there is a grain of truth to the claim, most people will not experience positive changes in their vision from eating carrots unless they have a vitamin A deficiency. Dietary supplement fact sheet: vitamin A and carotenoids. Accessed June 8, Recovery from impaired dark adaptation in nightblind pregnant Nepali women who receive small daily doses of vitamin A as amaranth leaves, carrots, goat liver, vitamin A-fortified rice, or retinyl palmitate.
Am J Clin Nutr. Kruszelnicki, KS. Great moments in science—carrots and night vision. Myths about Vision and Eyeglasses. Health and Age website. Accessed June 7, A case of carotenemia associated with ingestion of nutrient supplements. J Dermatol. There's hope for people with age-related macular degeneration. American Academy of Ophthalmology website. Dietary intake of antioxidants and risk of age-related macular degeneration. Though there is truth to this, the association between carrots and eyesight originated from a myth.
In an effort to keep this new technology a secret, the visual accuracy of the pilots — especially at night — was attributed to eating carrots. This led to a longstanding propaganda campaign that promoted carrots for better eyesight. This embellished link between eating carrots and improved night vision remains today. Carrots are a rich source of beta carotene and lutein, which are antioxidants that can help prevent eye damage caused by free radicals.
Free radicals are compounds that can lead to cellular damage, aging, and chronic illnesses, including eye diseases, when their numbers become too high 1. Beta carotene gives many red, orange, and yellow plants their coloring. Orange carrots are especially high in beta carotene, which your body converts into vitamin A.
Deficiency in vitamin A can lead to night blindness, which is often reversible by supplementing 2 , 3. Vitamin A is needed to form rhodopsin, which is the reddish-purple, light-sensitive pigment in your eye cells that helps you see at night 4. Your body absorbs and utilizes beta carotene more efficiently when you eat cooked carrots rather than raw ones.
Furthermore, vitamin A and its precursors are fat-soluble , so eating carrots with a fat source improves absorption 5 , 6 , 7. Yellow carrots contain the most lutein, which may help prevent age-related macular degeneration AMD , a condition in which your vision is gradually blurred or lost.
So how many carrots are ideal? Indeed, if a person eats too many carrots his or her skin may turn a bit orange—a harmless symptom that is not a health concern.
Most eye problems stem from vision-impairment caused by issues such as genetics, aging or diabetes that cannot be aided with an infusion of beta-carotene. The issue of night blindness is far from new. It was detailed in ancient Egyptian texts. When it comes to eating nutrient-rich foods to improve eyesight, more generally, Chew suggests stocking up on green, leafy vegetables.
Spinach, kale or collard greens—all chock-full of lutein and zeaxanthin which are other food-derived nutrients —could help protect your eyes by filtering high-energy wavelengths of visible light that can damage the retina.
Such foods may also help to protect against age-related macular degeneration, the major cause of blindness in the elderly. Dina Fine Maron, formerly an associate editor at Scientific American , is now a wildlife trade investigative reporter at National Geographic.
Already a subscriber? The studies concluded that patients with moderate and advanced AMD could benefit from antioxidant supplements. The American Academy of Ophthalmology offers this rundown on specific foods that are good for your eyes. Your eyes rely on tiny arteries for oxygen and nutrients, just as your heart relies on much larger arteries. That means you get a two-for-one benefit when you eat a rainbow of fruits and vegetables as well as omega-3 fatty acid-rich foods like salmon, tuna, and sardines.
In addition to carrots sweet potatoes have even more beta-carotene and other vegetables, fruits, cold-water fish, vitamin and mineral-rich foods, including eggs, beans, nuts, lean red meats, and poultry, all contribute to better vision at all stages of life.
While a lot of people may not realize it, good nutrition is incredibly important for overall eye health.
0コメント