- 十二月 11, 2019
Do carrots really help you see in the dark? What about kiwis
or kale? Can eating certain foods improve your eyesight or prevent
your eyes degenerating? Perhaps we should all be
taking supplements to benefit our vision? Research in both the US
and Ireland has shown that supplementing the diet with certain
key chemicals can significantly benefit your vision. These can
be taken as supplements but they are also found widely in many green
leafy plants and green and yellow fruit and vegetables.
报告标题：The Power of Small Molecules to Explain How We See and How We
We all know that the blue light that emits from our smartphones isn’t
good for our eyes, but a new study has discovered just how much damage
it can cause.
1. Your daily swim
报告人：Nasri Nesnas professor， Florida Institute of Technology
The retina is the part of our eye that contains cells sensitive to
light. The most delicate area of this tissue– the macula– is
protected from harmful blue and UV light by yellowish
‘macular pigment’. This acts like sunglasses, blocking the damaging
light. It comprises three pigments
–lutein,zeaxanthin and meso-zeaxanthin.
Researchers say that this light is absorbed by vital molecules in our
retina and triggers the production of a toxic chemical that kill cells.
Swimming is hugely beneficial for your cardiovascular system but if
you’re not wearing goggles, your eyes might be suffering, especially if
you’re a contact lens wearer and you open your eyes underwater.
A research team led by Professor Nolan in Ireland has recently completed
a year-long trial investigating the benefits of taking supplements of
macular pigments. 100 participants took part in the experiments. The
results showed that by taking lutein, zeaxanthin and meso-zeaxanthin,
there was a significant improvement in the protection of the macula, as
well as in overall eyesight. There was also some evidence that these
chemicals can help to slow down macular degeneration, which is the main
cause of sight loss in the UK. However, this is somewhat
Abstract:Vision is inarguably the most dependable of the five senses.
The retina contains light sensing protein receptors (rhodopsins) that
incorporate a small polyene molecule derivative of vitamin A, known as
11-cis-retinal. Major clues on understanding the visual cycle have been
established through the design of variations of the vitamin A light
absorbing molecule, some of which will be presented. A detailed
understanding of the inner workings of rhodopsin is not only critical
from the stand point of solving mysteries of visual diseases, like
Age-related Macular Degeneration (the leading cause of blindness), but
also serves as a well established model for elucidating the mechanism of
other G-protein coupled receptors . Furthermore, we show that the value
of light absorbing molecules expands beyond vision and can be used to
trigger neurons thereby aiding the delineation of complex neural
This damage can lead to large blind spots in our vision that are the
hallmark of macular degeneration, a disease that leads to blindness.
‘The water in pools, rivers and the sea, or even the shower can leave
your eyes vulnerable to bacterial infection,’ warns Vision Direct
optometrist Brendan O’ Brien.
Lutein is a yellow compound found only in plants, which produce it
to absorb light. We can get lutein by eating foods like kale and
spinach. It is also present in egg yolk. Zeaxanthin, another yellow
compound similar to lutein, is found in such foods as corn, yellow bell
peppers and saffron. Meso-zeaxanthin is not generally found in food
sources, though it can be found in some fish. It is created in the
retina from ingested lutein. It can be taken in supplements made
with marigold extracts.
The team from the University of Toledo in Ohio says it is urging the
public to not use phones in the dark because this can dilate pupils and
lead to even more harmful blue light entering our eyes.
‘The microorganism acanthamoeba lives in water and can cause serious
damage if it gets into your eye’.
As for carrots, it turns out that it’s the leafy green bits on the top
that contain the key compounds beneficial to eyesight, rather than the
vegetable itself. So next time you’re told carrots help you see in the
dark, save them for the rabbit and chop up some kiwi instead!
澳门新萄京最大平台：玩手机对眼睛到底有多大伤害，这8个日常习惯正在偷偷伤害你的眼睛。Age-related macular degeneration (AMD) is the leading cause of vision
loss for those aged 50 or older, according to the National Eye
‘Wearing contact lenses makes us more vulnerable because the bacteria
attaches to the lens and can cause the surface of your eye to become
inflamed and eventually infected,’ says O’Brien.
The condition occurs when the macula, an oval area near the center of
the retina that allows for sharp vision, becomes damaged.
Contact lenses will also naturally absorb any water around them, which
could change their shape dramatically. This will make them uncomfortable
to wear, often causing your vision to become distorted and blurry.
Sufferers will experience blurred vision or even ‘blind spots’ in their
central vision that may grow larger as the retina dies.
If you really must wear your lenses in the pool stick to daily
disposables along with waterproof swimming goggles, or better still
invest in a pair of prescription goggles which will help you see clearly
without water coming in direct contact with your eyes.
Treatments include medications that stop new blood vessels from forming
in the eye as well as laser therapies that destroy abnormal blood
2. Your out of date mascara
For this study, the team decided to focus on retinal, a form of vitamin
A found in the retina that coverts light into metabolic energy.
You know how your mascara gets all clumpy after three or four months,
but you don’t want to buy a new one because that stuff is pricey?
Photoreceptor cells, known more commonly as rods and cones, use retinal
to covert light into signals that are sent to the brain.
Well, it’s time to cull your make-up bag of all out of date eye make-up,
especially mascara, yes even your favorite Chanel one you bought in
‘The human eye reflects UV light (such as from the sun) very well but it
allows blue light to enter and the retinal can absorb blue light very
well,’ lead author Dr Ajith Karunarathne, an assistant professor in the
UT department of chemistry and biochemistry, told Daily Mail Online.
Mascara can harbor bacteria which can cause infections leading to
redness, light sensitivity and irritation and, in rare cases, even
blindness. Liquid liner and mascara have a shelf life of around three
months once opened.
Dr Karunarathne noted that blue light alone or retinal that hadn’t
absorbed blue light did not have any effect on the cells.
Unopened, well-formulated cosmetics can remain stable for a couple of
He added that there was no activity when retinal was exposed to other
light colors such as green, red or yellow.
澳门新萄京最大平台 ，What’s more, eye make-up applied inside the eyeline, such as eyeliner,
can increase the risk of eye infection, according to research from the
University of Waterloo published in the peer-reviewed journal.
The team did find a molecule, a vitamin E derivative known as alpha
tocopherol, that can stop the cells from dying.
The research by the scientist Dr Alison Ng found that contact lens
wearers were more vulnerable to infection from eye make-up. Dr Ng
recommends preventing bacterial transfer by sharpening eye pencils
thoroughly before each use.
‘When you damage the photoreceptor cells, they’re damaged for good, so
the vitamin E derivative currently just mitigates damage,’ said Dr
Similarly, false eyelashes could put your eyes at risk. According to
experts, false eyelashes are a hygiene risk because they tend to trap
dirt and bacteria, while poor quality, unhygienic lashes increase the
risk, so it’s important to find a reputable beautician.
‘We’re currently screening for more molecules to see if they can quench
this damaging reaction.’
3. Skipping your annual eye test
He explained that as we get older, the ability to prevent attacks from
retinal that has absorbed blue light became weaker, which leads to
‘An eye test can turn up health problems like diabetes, glaucoma and
high blood pressure, all of which can lead to serious eye problems and
even blindness if left unchecked,’ says O’Brien.
Dr Karunarathne says some of the ways we can protect ourselves include
wearing sunglasses that can filter both UV and blue light, using blue
light filters on our phones, and not looking at cell phones or tablets
in the dark.
Even arthritis which causes joint inflammation can be spotted with an
eye test, because the inflammation also turns up in the eye and will
eventually attack the eye too if left untreated.
‘Looking at cell phones in the dark can be very harmful because the
pupils are dilated so more blue light can get in and cause damage,’ he
‘Most optometrists recommended taking an eye test every two years,
unless you have eye issues or are over 70, in which case, a test every
12 months is best to catch any health problems early,’ says O’Brien.
‘Children up to the age of 16 should be tested annually too, according
to the College of Optometrists, as children’s vision can change very
rapidly at this stage of their lives.’
4. Staring at your smartphone
Staring at your smartphone or computer screen or TV for hours on end is
not good for your eye health, says research by the University of Toledo,
published in?Scientific Reports.
That’s because these screens emit blue light which is absorbed by vital
cells in the eye’s retina triggering toxic chemicals, which can
eventually kill the photoreceptors we need for vision. And the older you
get the more vulnerable you are.
The study’s lead researcher Dr Ajith Karunarathne, an assistant
professor in the UT department of chemistry and biochemistry says we
shouldn’t be checking phones and tablets in the dark, because this can
dilate the pupils making them more vulnerable to damage.
Dr Karunarathne explains wearing glasses with an anti-glare coating that
filters blue light, or adding a blue light filter screen to your phone
5. That casual smoking habit
We hardly need to say it: smoking is BAD, but few of us realize it
damages our eyes. ‘Smoking increases risk of cataracts and age related
macular degeneration (AMD), which is a common condition that affects the
middle part of your vision. In fact, AMD is Britain’s leading cause of
‘AMD occurs when the small central portion of the retina, known as the
macula, deteriorates and is the major cause of blindness in the over
fifties, ‘ says O’ Brien.
Risk of AMD doubles with smoking over fifty, says one British study
published in?The British Journal of Ophthalmology. So that’s another
reason to sign up for Stoptober.
6. Forgetting to wear sunglasses
You might think your sunnies are no longer needed now that the dark
nights are closing in. Not so says O’Brien. UV is still an issue on
overcast winter days.
‘Although the UV count is typically higher on sunnier days, it is
important to bear in mind that up to 80% of UV radiation can penetrate
cloud, meaning that forgetting to wear sunglasses on an overcast day can
still damage your eyes,’ says O’Brien.
‘That means it’s just as good an idea to pop on a pair of shades on a
sunny December morning as it is on a hot July afternoon.’
But don’t think just because your glasses are dark tinted they offer
ultra violet protection. ‘The tint of a sunglasses lens has no effect on
UV protection,’ says O’Brien.
‘While wearing darker lenses means that less light will enter your eye
and will help you see better, the same amount of UV is blocked as if you
were wearing shades with a lighter tint.’
And unless your sunglasses are offering good UV coverage, the tint means
they will dilate your pupils and allow more UV light in than normal, so
it’s potentially worse than going without sunglasses if your glasses
aren’t up to scratch.
The message? Don’t fall for those designer look-alikes, unless you can
verify their UV credentials. ‘Look for a CE mark (a European standard of
UV protection),’ says O’Brien.
Look for styles that fit close to your face and don’t let light in at
the side and if you’re a contacts wearer opt for brands like Acuvue with
UV filters included or remember to wear sunglasses with your contact
Warning: Your eyes are even more susceptible to burning than your skin.
As it’s harder to tell when your eyes are getting burnt than it is when
your skin starts turning red, it’s easy to end up doing lasting damage
to your eyes without knowing.
Frequent exposure to UV can lead to the development of eye conditions
such as cataracts and AMD which can impair sight and even cause partial
or total blindness.
Indeed, one systematic review published in 2014 of scientific research
on the subject found that sunlight exposure to eyes was a key risk
factor in the development of AMD.
7. Your fan
Leaving a fan running all night can increase irritation and dry eyes for
contact lens wearers. Why? Because fans blow allergens like dust or
pollen towards your eyes as you sleep, so that when you insert your
lenses in the morning these deposits cause irritation and discomfort.
The fix? Thoroughly dust bedroom surfaces, including the fan blades and
keep a bottle of contact lens solution handy to cleanse your lenses to
remove any impurities.
Consider setting a timer on your fan, so it switches off shortly after
you doze off and wear a sleep mask, so your eyes are protected.
8. Over-using eye drops
While it’s tempting to reach for the eye drops rather than put up with
looking like a pink-eyed bunny, you can have too much of a good thing,
say experts, as plenty of eye drops can lead to a rebound effect.
Rebound redness results because the blood vessels in the eye dilate as
the effects of the medication in the drops wears off, creating a vicious
circle. What should we do instead? ‘Try to pinpoint the cause and deal
with it, ‘ says O’Brien.
If, for example, your eyes are dry due to cold winter weather and
central heating, invest in a humidifier and try not to sit too close to
Rehydrate by drinking lots of water and eat plenty of foods rich in A, C
and E vitamins and omega-3 fats, like salmon. And when the wind starts
whistling, don your sunglasses to protect your eyes from the biting
How often you can use eye drops safely will depend on the type, says O’
‘There are two types: eye drops with preservatives and preservative-free
eye drops. Eye drops that contain preservatives have a longer shelf
life. The preservatives are chemicals that prevent bacteria from
growing. This allows you to use one bottle of eye drops for a length of
‘However, the preservatives in OTC eye drops cause eye irritation to
become worse. Eye specialists typically recommend that you use this type
of eye drop no more than four times a day.’ Preservative-free eye drops
are best for those with sensitive eyes.