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Why Do Onions Make Us Cry?

Onions are one of the most common staple foods around the globe. Ironically, for a vegetable so delicious, they can often be tear-jerkers.

Read on to learn why onions cause your eyes to tear and sting, and what you can do to minimize discomfort.

Why Does Cutting Onions Cause Tearing?

Onions produce a sulfur compound called propyl sulfoxide that is stored in the cells of the onion bulb (the part of the onion we eat). Onions grow underground, where they can be eaten by all types of creatures. This odorous sulfuric compound acts as a deterrent to small animals with big appetites.

When one slices into an onion and breaks open its cells, the sulfur compound is released and mixes with the moisture in the air — turning it into smelly and irritating sulfuric acid. When this chemical rises up and comes in contact with your eyes, it stings!

To keep your eyes from potentially being damaged from this chemical exposure, your brain triggers your eyes to tear and flush out the irritating gas particles. Once enough tears have flushed out the sulfuric acids particles from the eye, clear vision and comfort is usually restored. Although your eyes may sting and feel unpleasant, symptoms are temporary and the sulfuric acid won’t damage your eyes.

How Can I Reduce Eye Discomfort When Chopping Onions?

Most experienced chefs will tell you that chilling your onions in the fridge for at least 30 minutes before slicing them will reduce the amount of tearing they cause. Propyl sulfoxide escapes slower in cooler temperatures, reducing the amount of sulfuric acid in the air.

You can also try cutting the onions at arm’s length, or direct the odorous air away with a small fan. Some say that chopping onions immersed in water also helps. Another option is to wear kitchen goggles to protect your eyes.

Furthermore, try to use fresh onions whenever possible. The longer an onion has been stored, the more likely it will induce tearing and discomfort. Try to avoid slicing near the root end of the bulb, as that area has the highest concentration of sulfuric compounds.

Still Having Eye Problems Out of the Kitchen?

If you frequently suffer from eye irritation — and not just while cutting onions — we can help. At Optometry at Redwood Shores, we treat a wide range of eye conditions and can provide you with the treatment and relief you seek.

For further questions or to schedule an eye exam, call us today.

At Optometry at Redwood Shores, we put your family’s needs first. Talk to us about how we can help you maintain healthy vision. Call us today: 650-264-9887 or book an appointment online to see one of our Redwood City eye doctors.

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REFERENCES

https://www.britannica.com/story/why-do-onions-make-you-cry

https://theconversation.com/why-do-onions-make-you-cry-129519

Pink Eye? It Could Be Coronavirus

How to prevent conjunctivitis and protect your eyes

When you have a virus, especially one that causes a hacking cough, runny nose, and other symptoms of a common cold or flu, it’s typical for your eyes to also get puffy and red. You may be suffering from viral conjunctivitis, also known as pink eye.

How do viruses get into your eyes?

It’s rather simple. When you’re sick, you can easily transfer viruses to your eyes by sneezing, coughing into your hands, or blowing your nose – and then touching the area around your eye.

The coronavirus – pink eye connection

According to the American Academy of Ophthalmology (AAO), doctors have discovered that COVID-19 can cause conjunctivitis. If you’re standing within six feet of an infected person, and they cough or sneeze, the virus can enter your eye. Alternatively, if someone sneezes and virus particles land on the shopping cart that you take and push around a store, and then you touch your eyes without washing your hands first – you’re giving the virus direct access.

However, despite the apparent ease with which coronavirus can infect eyes, the AAO reports that only about 1 – 3% of all patients with the virus contract pink eye.

Preventing pink eye

Like always, prevention is the most effective medicine! Eye care professionals recommend following these tips to help prevent getting viral conjunctivitis:

  • Wash your hands correctly

The CDC instructs people to wash their hands in accordance with these steps: wet your hands, turn off the tap, apply soap, lather and scrub for 20 seconds, turn on tap and rinse. Air dry your hands, use a disposable paper towel and discard it immediately, or use a clean (not shared) towel.

  • Keep your fingers away from your face

No rubbing or wiping your eyes! Even if you don’t feel any symptoms of coronavirus, it’s essential not to touch any part of your face. To wipe away tears or remove makeup, use a clean tissue.

  • Don’t share your personal things

As generous as you may feel about letting others use your personal items, now’s the time to keep things to yourself. For example, the CDC recommends not sharing eye drops, makeup, makeup brushes, contact lenses cases, pillowcases, or towels. Pink eye is highly contagious.

  • Consider wearing glasses instead of contacts

While there’s currently no evidence to prove that wearing contacts raises your risks of contracting the novel coronavirus, there’s some evidence that shows you can get Covid-19 by touching a contaminated surface and then touching your eyes. In general, contact lenses wearers touch their eyes more often than people who wear eyeglasses, so it may be smart to make a temporary switch from contact lenses to glasses. However, this is only a friendly recommendation and not a hard-and-fast rule. If you prefer to stick with wearing contacts, washing your hands thoroughly can help keep you and your eyes safe.

Treatment for conjunctivitis

Regardless of whether your pink eye is caused by coronavirus or a different virus, there is no treatment for viral conjunctivitis. Usually, it goes away on its own within one to two weeks.

To alleviate your painful symptoms, eye doctors recommend:

  • Taking an over-the-counter pain medication, such as acetaminophen, ibuprofen or any anti-inflammatory drug
  • Applying a warm compress on your eye for a few minutes; take care to use a clean wash cloth each time and for each eye
  • Use artificial tears (lubricating eye drops) to soothe your eye irritation; don’t touch the bottle tip to your eye

Are you sick and have pink eye symptoms?

Now is not the time to make a DIY diagnosis. Eye redness, even if you have a virus, doesn’t necessarily indicate that you have conjunctivitis. A wide range of other conditions can lead to the same symptoms. Contact an eye doctor near you for help to figure out what’s causing your eye pain. Don’t visit your eye care practice without calling for guidance first, because extra precautions must be taken with patients who may have COVID-19.

At Optometry at Redwood Shores, we put your family’s needs first. Talk to us about how we can help you maintain healthy vision. Call us today: 650-264-9887 or book an appointment online to see one of our Redwood City eye doctors.

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Trouble Seeing at Night? All About Night Blindness

At this time of year when the sun sets earlier, many people are affected by night blindness. Night blindness or nyctalopia refers to difficulty seeing at night or in poor or dim lighting situations. It can be caused by a number of underlying conditions, sometimes completely benign and sometimes as a symptom of a more serious eye disease. So, if you are experiencing trouble seeing in low light, especially if it is a sudden onset of the condition, it is worth having it checked out by your eye doctor.

Signs of Night Blindness

The main indication of night blindness is difficulty seeing well in dark or dim lighting, especially when transitioning from a brighter to a lower light environment, like walking from outside into a dimly lit room. Many experience difficulty driving at night, particularly with the glare of streetlights or the headlights from oncoming traffic.

Causes of Night Blindness

Night blindness is a condition that can be present from birth, or caused by a disease, injury or even a vitamin deficiency. In order to treat the condition, your eye doctor will need to determine the cause. Here are some of the common causes:

  • Nearsightedness (myopia) – many people with nearsightedness (or difficulty seeing objects in the distance) experience some degree of night blindness, especially when driving.
  • Retinitis Pigmentosa – a genetic condition in which the pigmented cells in the retina break down causing a loss of peripheral vision and night blindness.
  • Cataracts – a clouding of the natural lens of the eye causing vision loss.
  • Glaucoma – a group of diseases that involve damage to the optic nerve and subsequent vision loss.
  • Vitamin A Deficiency – vitamin A or retinol is found in greens (kale, spinach, collards, broccoli etc.), eggs, liver, orange vegetables (carrots, sweet potatoes, mango etc.), eggs and butter. Your doctor may also prescribe Vitamin A supplements if you have a serious deficiency.
  • Eye Surgery – refractive surgery such as LASIK sometimes results in reduced night vision as either a temporary or sometimes permanent side effects.
  • Injury – an injury to the eye or the part of the brain that processes vision can result in reduced night vision.
  • Uncorrected Visual Error – many people experience better daytime vision as the pupils are smaller and provide greater depth of field to compensate for any vision problems. At night, the pupils dilate, so blur is increased from uncorrected nearsightedness, farsightedness, astigmatism or distortions/aberrations on the cornea from refractive surgery. Even a slight prescription for someone who may not need glasses during the day can make a significant improvement in night vision.
  • Eyewear Problems – even if your vision correction is accurate, badly scratched glasses or poor/defective lens coatings can also cause trouble seeing at night. Special lens coatings are now available on glasses for night time and foggy conditions.

Treatment for Night Blindness

Some causes of night blindness are treatable, while others are not, so the first step is a comprehensive eye exam to determine what the root of the problem is. Treatments range from simply purchasing a special pair of glasses, lens coatings or contact lenses to wear at night (for optical issues such as myopia) to surgery (to correct the underlying problem such as cataracts), to medication (for diseases like glaucoma). In some cases, your doctor may recommend that you avoid driving at night. During the day, it may help to wear sunglasses or a brimmed hat to ease the transition indoors.

As with any change in vision, it is critical to get your eyes checked as soon as you begin to experience symptoms, and on a routine basis even if you’re symptom-free. Not only will this improve your chances of detecting and treating a vision-threatening disease if you have one brewing, but treatment will also keep you more comfortable seeing in low-light, and keep you and your loved ones safe at night or in poor light conditions.

At Optometry at Redwood Shores, we put your family’s needs first. Talk to us about how we can help you maintain healthy vision. Call us today: 650-264-9887 or book an appointment online to see one of our Redwood City eye doctors.

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Diabetes Awareness Month – Learn about Diabetic Eye Health in Redwood City

November is Diabetes Awareness Month, a time to learn more about diabetes of all types – type 1, type 2, and gestational diabetes.

Everyone knows the word “diabetes,” but can you define the condition? Diabetes is a disease characterized by higher than normal glucose levels in your blood. Blood glucose is what fuels your body, and it comes from the food you eat. When blood sugar flows through your bloodstream, insulin is needed to help it enter your body cells so it can be used for energy. However, if you have diabetes, your body may make insufficient insulin or not be able to use the insulin properly. As a result, all that sugar stays circulation in your blood – unable to be converted into energy.

Diabetes can be managed very well through diet, exercise, and taking medication. Without controlling diabetes by keeping blood sugar levels within the parameters recommended by your doctor, the high blood sugar can damage many organs – including your eyes. Staying healthy by following your personalized diabetes management plan and making sure to visit your eye doctor for regular eye exams, you can pave your path to good vision and eye health!

Diabetic eye health & diabetic eye disease

To state the facts – diabetes-related eye disease can lead to vision loss, but if you have diabetes, you can minimize your risk of developing diabetic eye disease. Taking charge of your health and visiting our Redwood City eye doctor for regular eye exams can help prevent these diseases from developing.

Diabetic eye disease comprises several ocular conditions:

  • Diabetic retinopathy – occurs when the small blood vessels in your retina bleed and leak
  • Macular edema – swelling that occurs along with retinopathy; it happens when the retinal blood vessels in the macula (central region of the retina) leak and lead to inflammation
  • Cataracts – a clouding of the lens in the eye, which can cause blurry vision
  • Glaucoma – increased intraocular pressure, which damages the optic nerve and can cause loss of peripheral vision

Diabetes eye exams

With regular check-ups by our Redwood City eye doctor, you can help prevent eye problems or keep the problems minor. One mistake that many people with diabetes make is to assume that a diabetes eye exam is only necessary if they notice any symptoms. This couldn’t be further from the truth! A comprehensive eye exam is the only reliable way to detect several eye conditions that can cause vision loss, such as diabetic retinopathy, glaucoma, and cataracts. Early detection of these problems can make the difference between effective, successful treatment and damage to your vision. During your dilated eye exam, the eye doctor will use high-powered magnification to inspect the inner tissues of your eye thoroughly, checking the retina for signs of diabetic retinopathy and checking the optic nerve for any damage.

According to the American Diabetes Association (ADA) guidelines:

  • People with type 1 diabetes should have their first diabetic eye exam within the first five years
  • People with type 2 diabetes should visit their eye doctor for the first diabetic eye exam immediately after diagnosis. Type 2 diabetes can remain undetected for years, and vision damage can occur during this time.
  • Women with gestational diabetes should have an eye exam during the first trimester of pregnancy

After the first diabetic eye exam at Redwood City, our eye doctor advises all adults with diabetes to visit yearly for a comprehensive dilated eye exam.

At Optometry at Redwood Shores, we put your family’s needs first. Talk to us about how we can help you maintain healthy vision. Call us today: 650-264-9887 or book an appointment online to see one of our Redwood City eye doctors.

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6 Tips for Having Healthy Eyes & Contact Lenses

Your eyes do so much for you every day, show your love and appreciation by taking care of them! When you wear contact lenses, caring for them properly will help keep your eyes and your vision in top shape. However, if you don’t practice correct hygiene and handling with your contacts, you increase your odds of getting a serious eye infection and put your sight at risk.

Read the following contact lenses health tips from our friendly, knowledgeable eye doctor near you to ensure that you give your eyes the attention they deserve:

1. Keep your contacts away from water

Yes, that includes showering, swimming, and rinsing or storing your contact lenses in water. Although water may look clean and sparkling, it’s actually teeming with dangerous germs that can transfer into your cornea and lead to a sight-threatening eye infection. In particular, water-borne bacteria can cause acanthamoeba keratitis, a rare eye infection that can lead to blindness.

Recently, a woman in England was diagnosed with acanthamoeba keratitis after showering and swimming in her contact lenses. An article published in the New England Journal of Medicine, in July 2019, reported how the woman wore monthly disposable soft contact lenses and began to experience painful, blurry vision and light sensitivity in one eye. After two months of these disturbing symptoms, she booked an appointment with her eye doctor.

At her eye exam, it was discovered that her vision in her left eye was only 20/200. By taking a corneal scraping and inserting dye into her eye, her eye doctor was able to confirm a diagnosis of acanthamoeba keratitis. She was treated with antimicrobial eye drops, and the infection cleared up. However, her vision loss remained due to a corneal scar and a cataract that had developed. About a year later, she had eye surgery that was able to relieve all pain and restore her vision to 20/80.

Why is the risk of acanthamoeba keratitis higher for contact lenses wearers?

This uncommon, aggressive eye infection affects only one to two million contact lenses wearers in the United States per year. It shows up more frequently in people who wear contacts because the lenses absorb water and anything contained in that water. As contacts rest directly on top of your eye, they provide a clear path to your cornea. Acanthamoeba keratitis must be treated immediately, because it can damage vision quickly.

To protect against all types of eye infection, our eye doctor near you recommends never coming into contact with water while you are wearing contact lenses!

2. Treat your contact lenses to fresh solution every time you clean or store them.

Never top up used solution with additional new solution to make the bottle last longer! Doing this reduces the cleaning power of your disinfectant, leaving your contact lenses susceptible to bacteria.

3. Don’t sleep with contact lenses, unless your eye doctor lets you

Sleeping with contacts is contraindicated, unless your eye doctor instructs you that your type of contacts is suitable for overnight wear. Many scientific studies have shown that wearing lenses while sleeping raises the risk of eye infection six to eight times higher!

4. Clean your contacts by rubbing them

According to the American Academy of Ophthalmology, not only should you clean your hands well before touching your contact lenses, but you should also take care to rub your contacts. Rubbing your lenses helps to loosen any bacteria build-up, and studies show it’s a very effective way to reduce your chances of getting an eye infection.

5. Throw out your contact lenses on time

Only wear your lenses for the duration of time that your eye doctor recommends. For example, if you have monthly contact lenses – don’t continue to wear them after 30 days have passed.

All of the above tips from our eye doctor near you will optimize the health of your eyes as you enjoy the clarity and comfort of wearing contact lenses!

Is School Work Causing Computer Vision Syndrome in Your Child?

Eye health tips for students from our Redwood City eye doctor

The start of fall means back-to-school for kids of all ages – and our team at Optometry at Redwood Shores wishes everyone a smooth and successful return to the classroom!

When your child enters school after a summer of outdoor fun, many of the summer’s vision hazards are left behind. Yet, that doesn’t mean all eye health risks are eliminated! Nowadays, the majority of learning is computer based – exposing students’ eyes to the pain and dangers of blue light and computer vision syndrome. Fortunately, a variety of helpful devices and smartphone apps are available to block blue light and keep your child’s vision safe and comfortable.

To help you safeguard your child’s vision for the upcoming semesters and the long term of life, our Redwood City optometrist explains all about computer vision syndrome and how to prevent it.

Symptoms of computer vision syndrome

It’s smart to familiarize yourself with the signs of computer vision syndrome. If your child complains about any of these common symptoms, you can help prevent any lasting vision damage by booking an eye exam with our Redwood City eye doctor near you:

  • Eye irritation and redness
  • Neck, shoulder and back pain
  • Blurry vision
  • Dry eyes, due to reduced blinking
  • Headaches

Basics of blue light

Students spend endless hours in front of digital screens, be it a computer monitor, tablet, or smartphone. There is homework to be done, research to be conducted, texting with friends, and movies and gaming during downtime. All of this screen time exposes your child’s eyes to blue light.

Many research studies have demonstrated that flickering blue light – the shortest, highest-energy wavelength of visible light – can lead to tired eyes, headaches, and blurry vision. Additionally, blue light can disrupt the sleep/wake cycle, causing sleep deprivation and all the physical and mental health problems associated with it. As for your child’s future eye health, blue light may also be linked to the later development of macular degeneration and retinal damage.

How to avoid computer vision syndrome

Our Redwood City eye doctor shares the following ways to block blue light and protect against computer vision syndrome:

  • Computer glasses, eyeglasses lenses treated with a blue-light blocking coating, and contact lenses with built-in blue light protection are all effective ways to optimize visual comfort when working in front of a screen. These optics reduce eye strain and prevent hazardous blue-light radiation from entering the eyes.
  • Practice the 20-20-20 rule; pause every 20 minutes to gaze at an object that’s 20 feet away for 20 seconds. This simple behavior gives eyes a chance to rest from the intensity of the computer or smartphone screen, preventing eye fatigue.
  • Prescription glasses can be helpful when using a computer for long periods – even for students who don’t generally need prescription eyewear. A weak prescription can take the stress off of your child’s eyes, decreasing fatigue and increasing their ability to concentrate. Our Redwood City optometrist will perform a personalized eye exam to determine the most suitable prescription.
  • Moisturize vision with eye drops. One of the most common symptoms of computer vision syndrome is dry eyes, namely because people forget to blink frequently enough. Equip your child with a bottle of preservative-free artificial tears eye drops (available over the counter) and remind them to blink!
  • Blue light filters can be installed on a computer, smartphone, and all digital screens to minimize exposure to blue. A range of helpful free apps are also available for download.
  • Limit screen time for your child each day, or encourage breaks at least once an hour. Typically, the degree of discomfort from computer vision syndrome is in direct proportion with the amount of time your child spends viewing digital screens.
  • Set the proper screen distance. Younger children (elementary school) should view their computer at a half-arm’s length away from their eyes, just below eye level. Kids in middle school and high school should sit about 20 – 28 inches from the screen, with the top of the screen at eye level.

For additional info, book a consultation and eye exam at Optometry at Redwood Shores

When you and your child meet with our Redwood City eye doctor, we’ll ask questions about your child’s school and study habits to provide customized recommendations on the most effective ways to stay safe from computer vision syndrome and blue light. Our optometrist stays up-to-date with the latest optic technologies and methods to prevent painful vision and eye health damage from using a computer, so you can depend on us for contemporary, progressive treatment.