Eight hours in a chair in front of a computer, five days a week can take a toll on your body. From avoiding eye strain and tension neck syndrome to passing on those extra calories that co-workers leave invitingly on their desks, experts give 10 tips that will help you stay healthy and in shape at work.

Eight hours in a chair in front of a computer, five days a week can take a toll on your body. From avoiding eye strain and tension neck syndrome to passing on those extra calories that co-workers leave invitingly on their desks, experts give WebMD 10 tips that will help you stay healthy and in shape at work.

1. The snacks that your co-workers so nicely place on their desk can add a few hundred calories to your daily diet if you're not careful, and they can leave you with unwanted pounds if you help yourself day after day.

"If it's out of sight, it's out of mind, so if you know someone has a candy dish on their desk, walk around his or her desk so you don't feel the temptation," says Dawn Jackson, a registered dietitian and spokeswoman for the American Dietetic Association. "Take a break, get a breath of fresh air, and skip the candy. Or, if you are hungry, have fruit at your desk, like cherries or grapes."

Three out of five Americans are overweight, explains Jackson, which means there is likely more than one person in your office who is dieting.

"In most offices, people are trying to lose weight, so go in with people and get fruit bowls instead of candy bowls," says Jackson. "And see if you can get people to replace their candy bowls with something healthier."

2. Drinking an adequate amount of water -- eight to 10 glasses every day -- can help keep you hydrated. Many foods are also good sources of water; fruits like oranges, grapefruit, grapes, watermelon, and apples can help keep you healthy and hydrated.

"The 3 o'clock lull that many people feel at work can be due to dehydration, so drink lots of water," Jackson tells WebMD. "Set goals: Bring a 16 ounce bottle of water to work and try to finish it by lunch, and then fill it up again and finish that by 3 p.m. By 5 p.m., finish a third bottle."

Another tip from Jackson: Set your computer alarm to go off so you remember it's time to refill.

3. One of the most important things you can do during the day to stay healthy and in shape is to exercise.

"Walking during lunch is a great idea," says Jackson. "Not only are you burning calories, but you're de-stressing and refreshing."

Jackson recommends you find a walking partner whom you can depend on for a daily walk --someone who will drag you out even if you claim you're too busy. If you really can't get out during lunch, park farther away than you normally do so you have a short walk to work in the morning and evening, or make it a habit to take the stairs instead of the elevator.

4. Eating a healthy lunch is an important part of a balanced diet. But eating reasonable portions is an important part of your health.

"Eat a healthy lunch at work, but also practice portion control so you aren't consuming too many calories and then sitting in a chair all afternoon," says Jackson. "Many times, it's not that you are eating unhealthy food, it's just that you are eating too much."

For instance, Jackson explains that pizza isn't inherently bad, it's just that a person will eat three or four slices too many, and that's where the problem lies. Instead, share a large slice of piece of pizza with a co-worker, and then eat a salad that's packed with veggies.

5. Tension neck syndrome (TNS) can occur when the neck and upper shoulders are held in a fixed, awkward position for long periods of time, according to the National Institute of Environmental Health Sciences. It can happen to people in the workplace who talk on the phone for a most of the day or type a lot.

"You want to make sure your neck isn't bent to the side for long periods of time, " says Alan Hedge, professor of ergonomics at Cornell University. "Tension neck syndrome can cause neck and shoulder pain, muscle tightness, and tenderness. So use a speakerphone, a shoulder cradle, or use a headset at work when you're on the phone."

6. Eyestrain is another problem that can be encountered in front of a computer. It can cause headaches, difficulty focusing, and increased sensitivity to light, according to the University of California at Davis.

To prevent eyestrain, Hedge tells WebMD, "The distance to the screen from your eyes should be about an arms length away. You should also be able to comfortably read what's on your screen at that distance, without having to squint."

If you can't read your screen from an arm's length away, simply increase the font size on your computer.

7. A healthy tip that all of us want to hear is that vacations are an important part of staying healthy at work.

"It's very beneficial to get away for a long vacation that will help you recharge your 'batteries,'" says Jonathan Kramer, a clinical psychologist and president of Business Psychology Consulting. "Vacations help reduce stress and get your mind off work, especially if you're having a conflict, such as a problem with your boss, a co-worker, or a project."

Stress can impair your immune system, increasing the risk of illness, explains Kramer, so minimizing it is essential -- and fortunately, vacations are just the way to do that.

8. Another way to stay healthy at work is to avoid long stretches of long days.

"Occasionally, people focus on the task at hand and getting a project done, and they aren't aware of the impact it's having on their health," says Kramer. "They may not be aware of it until the stress is at a really high level, and it's affecting their relationships and their moods."

This, explains Kramer, is another type of stress, commonly referred to as burnout. Burnout can also impair a person's immune system, as well as interfere with sleep and his or her ability to concentrate.

9. Your keyboard, mouse, and phone can harbor thousands of germs that are just waiting to make you sick. So get out the disinfectant.

According to Science Daily, researchers at the 100th General Meeting of the American Society for Microbiology reported, "We know that viruses can survive (remain infectious) for hours to days on a hard surface ... if a virus such as the rotavirus (a diarrheal virus) were on the surface of a telephone receiver, infectious doses could easily be transferred to persons using the telephone."

To clean these objects, the National Consumers League recommends using a disinfectant cleaner or spray that is registered with the Environmental Protection Agency and proven effective against a wide variety of viruses.

10. What's the most important thing you can do to stay healthy at work? Kramer sums it up for WebMD.

"The most important way to stay healthy at work starts with self-awareness," says Kramer. "Know yourself and know your limits and do the best you can to stay within those limits given your job. Know when to take breaks and know when to take a vacation. And get plenty of exercise, which helps you both physically and mentally, both at work and at home."