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Expert Q&A: Your Top Vision Questions Answered

May is Healthy Vision Month, so it’s a great time to reflect on the important ways you can proactively protect your sight. Delta Dental of Iowa asked Dr. Chad Overman, our director of vision benefits, to answer our top eye health questions and inspire our members to take a closer look at their eye health.

Q: We know wearing sunglasses is important to protecting our eyes from the sun. What do people need to know about sunglasses to ensure they're getting the best possible protection?

Dr. Overman: When it comes to sunglasses, UV transmission is the key. UV rays—or ultraviolet rays—are the harmful light rays that can damage your skin and your eyes. You want to ensure that your sunglasses offer as close to 100% UV protection as possible; this means that the lenses will block harmful UV rays from reaching your eyes.

You want your sunglasses to block as much UV light as possible, and over-the-counter sunglasses often do not do a good job of totally blocking these rays. In addition to UV protection, I also suggest purchasing polarized sunglasses as these lenses will reduce glare (an important factor, especially if you’ve ever dealt with blinding glare while driving).

Sunglasses range greatly in price and quality, and it can be challenging to select a pair that is worth the money. It’s a good idea to ask your eye doctor for his or her recommendation on quality sunglass brands that take your specific eye health and budget needs into account.

Q: Staring at computer and device screens for long periods is part of daily living for many. Why should people be concerned about their screen time use as it relates to eye health – and what can they do to minimize these risks?

Dr. Overman: Digital eyestrain is a real thing. What most people don’t realize is we tend to not blink as often when we are on digital devices. As we look at a digital device, we tend to stare, so we blink about a third as much as we do when we’re not looking at a screen. This leads to eye dryness and strain.

Our visual system is not meant to stare at screens all day, so our eyes tire over the course of the day. Nevertheless, using computers, phones and tablets is a part of modern daily living.

To combat the effect, I am an advocate of the 20/20/20 rule that should be used throughout the day. Here’s how it works: You should look 20 feet away for 20 seconds every 20 minutes. This exercise gives your eyes a break and allows them to relax and refocus. While doing this, it is also wise to excessively blink to ward off dryness and get your tears working properly.

Q: Diet is a crucial element to overall health. What foods/nutrients have been shown to support eye health?

Dr. Overman: Omegas, especially omega-3 fatty acids and lutein are very important to eye health. These are antioxidants proven to bolster the tissues of the eyes and improve both function and protection.

Many types of fish are rich in omegas, as are walnuts, flax seeds and chia seeds. Green leafy vegetables are the best sources of lutein. You can also purchase supplements containing these nutrients that are designed to boost eye health.

Q: One of the lesser-known links to good eye health is physical activity. Can you share why staying active is good for your eyes?

Dr. Overman: Physical activity is important for your eyes for the same reasons it is good for the rest of your body. Increasing blood flow, decreasing blood pressure, cholesterol and blood sugar and strengthening vessels are all important aspects of an exercise program—and they all help promote long-term eye health.

Q: What's the one thing people can do today to improve the long-term health of their eyes?

Dr. Overman: Have a yearly eye exam and stop smoking! Smoking causes oxidation issues with all your body’s tissues, including your eyes.  I mentioned omegas and lutein as antioxidants for your eyes—smoking does the opposite.  Macular degeneration, a prominent eye disease that progressively causes vision loss, is heavily affected by smoking.

With Healthy Vision Month fast approaching, there’s no better time to make changes to proactively protect your eye health. Delta Dental of Iowa offers DeltaVision for individuals, families and older Iowans who also have our dental coverage. Learn more about DeltaVision and get covered.

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Shifting Shades: What Color Should Your Teeth Be? 

When it comes to teeth color, one shade pops to mind: white – pearly, sparkling, brilliant white. In reality, teeth come in an array of shades. Many factors influence the color of your teeth, but your dentin is primarily responsible.

Dentin Defined

The color of your teeth is determined by dentin, which is the main bony part of your tooth that lies just below your enamel. Dentin isn’t typically a perfect white color; it actually has a gray or yellowish tint. The darker the dentin, the more likely it can show through the bluish-white enamel outer layer of the tooth.

A Closer Look at Colors


Not surprisingly, baby teeth (primary teeth) are typically whiter than adult teeth (permanent). The dentin of baby teeth is very light yellow, almost white, so it’s not dark enough to show through the translucent enamel covering. Baby teeth also look extra white because the primary tooth structure is more calcified.

Light gray or light yellow

As people age and lose their primary teeth, their permanent teeth take on a light gray or light yellow shade. This is because the color of your dentin darkens as you get older. As your dentin becomes more yellow or gray, it’s more likely to show through your enamel.


Yellow teeth are usually the result of years of staining from certain foods and drinks. Typical teeth-staining culprits include coffee, tea, soda and wine as they have strong colors that bind to your enamel. Aging also shifts the shade of your teeth toward the yellow end of the spectrum. Another cause of yellow teeth is tartar. If you haven’t been to the dentist in a while for a good cleaning or you don’t floss, your yellow teeth may be from tartar. Tartar is naturally yellow, and it can permanently stain your teeth yellow if it sticks on your teeth too long.


Brown or dark brown teeth are considered advanced tooth staining. Brown teeth are usually caused by tobacco use (chewing or smoking), but age, genetics and some medications can also darken your teeth. If you notice brown spots on your teeth, talk to your dentist as this could be a sign of tooth decay.

Should You Whiten Your Teeth?

Expecting a naturally white smile throughout your life might not be realistic, but several products are available to help whiten teeth. Before starting a whitening regimen, it’s important to talk with your dentist. Your dentist will share recommended over-the-counter products and help you avoid common complications (like tooth sensitivity) and pitfalls (whitening may not work on all teeth, particularly if you’ve had crowns or fillings).

If you would like to explore your dentist’s clinical-level whitening programs, we recommend you call your Delta Dental of Iowa customer service number on the back of your ID card to understand your coverage around whitening procedures, as these treatments are typically not covered under most dental plans.

Fortunately, your twice-yearly preventive exams are always covered. These visits are excellent opportunities to not only get a professional cleaning but also to talk with your dentist about ways you can whiten your teeth between appointments.