Most people know what stresses them out. It could be their boss, the in-laws, or even their physical fitness. What guys don’t expect are seemingly harmless things you do every day to be building up tension in ways science is just beginning to understand.

Here are 5 things that are secretly causing you stress:

1. Cell Phones

There’s a cost to having all the power of a computer in your pocket. The convenience of that super-powered cell phone comes at the price of your ability to concentrate for extended periods of time.

According to a study by Loughborough University, every time you check text messages, email, or one of the apps on your smartphone, it takes 64 seconds before your brain can get back to whatever you were doing before. Those 64 seconds accumulate and gradually begin to stress you out.

Since the average Canadian checks their phone every 5 minutes, this means most people are struggling to get back on task for 8.5 hours a week. Instead of constantly checking your phone throughout the day, set aside five minutes every hour to get everything done in one go.

2. Computers

Whether you enjoy spending time on a computer or not, research is beginning to show that regular computer usage leads to higher levels of stress.

According to Dr. Erik Peper, Director of San Francisco State University’s Institute for Holistic Healing, “Your breathing rate goes up 30 percent, your blinking rate goes way down, and you tend to tighten your arms and shoulders without knowing it.” These side effects add a considerable amount of physical tention and leave you more irritable throughout the day.

To counter these symptoms, it’s important to take short breaks to walk, stretch your muscles, close your eyes for a bit, and flex your wrists.

3. Background Noise

When you think you’re in a quiet room, chances are you’ve just acclimatized to the constant stream of sounds around you. The engines humming from cars outside, the kids playing down the street, or the faint buzzing from the refrigerator are common examples of background noise.

According to a study commissioned by the Austrian Ministry of Health, the noisier your neighborhood, the higher your blood pressure, heart rate, and level of stress hormones. That means when it comes to stress, silence really is golden.

It’s not easy to rid yourself of all background noise, but do your best to find some peace and quiet every day, and you’ll find yourself feeling refreshed and hopefully less stressed.

4. Driving

Even if you don’t give in to road-rage, your daily commute has lasting effects on your temperament throughout the day. According to a Canadian study lead by Dr. Dwight Hennessy, adult men who have an irritating drive to work were more likely to behave hostile and act stressed out.

Those who aren’t in as much of a hurry aren’t affected to the same degree. “People who have more flexibility in their work environment have less stress when they drive, because the time factor isn’t such a big concern,” says Dr. Hennessy.

One way to calm your nerves while on the road is to give yourself some extra time to get from point A to point B, that way even if you hit traffic or need to stop for gas, you’ll still make it on time.

5. Lighting

Not many people have ever experienced total darkness. There’s always a sliver of light creeping in from under the door, or a blue glow coming from your computer across the room.

According to research by Dr. Joshua Gooley of Harvard Medical School, “This exposure to indoor light has a strong suppressive effect on the hormone melatonin.” You may think you’re getting a good nights sleep, but if you’re sleeping with the lights on your melatonin levels are likely off. “This could, in turn, have effects on sleep quality and the body’s ability to regulate body temperature, blood pressure and glucose levels,” says Dr. Gooley.

To keep your melatonin happy, it’s important to sleep in a dark room. If possible, adapt your sleeping schedule to match when the sun is down, and consider getting blackout curtains.