Our annual “fall back” time change that gives us an extra hour of sleep is welcome news for most of us. But there are some unintended consequences of darker evenings, especially for drivers. According to the National Safety Council, traffic death rates are three times greater at night than during the day.
In a special rebroadcast of the Healthy Vision with Dr. Val Jones show, I interviewed Dr. Christina Schnider, Senior Director, Professional Communications for VISTAKON® Division of Johnson & Johnson Vision Care, about common nighttime driving problems such as dry eyes, headaches, and eye fatigue. I also spoke with John Ulczycki, Group Vice President – Strategic Initiatives, for the National Safety Council, about safe driving tips. You can listen to the show here:
Most people experience a drop in visual acuity in the dark, and this can cause difficulty seeing traffic signs, pedestrians and roadside objects. The primary reason why it’s difficult to see at night is that our pupils dilate to let in as much light as possible. The trade off with large pupils is that visual acuity suffers. It’s normal for the average person’s visual acuity to drop from 20/20 to 20/40 in low light conditions.
Because of vision challenges, driving in low-light conditions can fatigue the eyes and head and neck muscles as the driver strains to see the environment more clearly. Dry eyes can occur from reduced blink rates and motor vehicle heating and cooling systems. Glasses wearers may have a reduced field of vision which further complicates driving in the dark. In fact, in a recent survey one -in-three drivers reported that they didn’t see well at night.
Dr. Schnider and Mr. Ulczycki suggest that night time driving may be safer (and more comfortable) with these tips:
1. Update your eyeglass or contact lens prescription(s). Since darkness reduces visual acuity, wearing lenses that correct your vision to 20/20 in normal light conditions is extra important. Old glasses or contacts with outdated vision correction power can make driving in the dark more hazardous. If you experience significant challenges seeing at night, you may have a condition called “nighttime myopia” and should visit your eye doctor for advice.
2. Avoid driving long distances in low-light conditions. Since we already know that driving in the dark can cause eye fatigue, dry eyes, and reduced visual acuity, it’s best to minimize the time you spend behind the wheel during dark hours. Whenever possible, plan your travel so that the majority of your driving time occurs during daylight hours.
3. Take frequent breaks. Even though it’s tempting to push through your fatigue and finish driving those last miles to your destination, it’s safer to give yourself (and your eyes) a break. Stopping for gas or at a rest area may improve your alertness and visual fatigue. Remember that impaired drivers are more likely to be on the road at night, so vigilance on your part may prevent an accident.
4. Decrease your night-time driving speed. If you do need to drive in the dark, doing so more slowly may prevent accidents. Traveling at a slower speed can improve reaction time under lower-visibility conditions.
5. Check your headlights. It is estimated that 50% of all motor vehicle headlights are not optimally aligned. Potholes and bumps in the road can jolt the lights out of alignment. It’s important not to look directly at oncoming headlights. This can temporarily blind you as your pupils adjust to a quick change in lighting conditions.
For more safety tips, please listen to the full Healthy Vision podcast.
*Val Jones, M.D. is a paid consultant for Johnson & Johnson Vision Care, Inc.*