We know smoking is bad for us. We've all heard that being inactive puts us at higher risk for health problems. And who hasn't been told to put sunscreen on to protect their skin? There are a litany of ways to ruin your health, many of which we already aware. But as you've probably heard before: What you don't know can hurt you. Here, six unexpected factors that may be detrimental to your health.

1. Using the computer

In the age of the Internet, few Americans go a day without using a computer. Although your seemingly harmless computer may be the center of your work-life, it can have real-life health effects. Eye strain, carpal tunnel syndrome, neck and back strain are possible issues associated with long hours spent in front of the computer screen. Furthermore, a study conducted by Statistics Canada found that adults who spend over three hours a day sitting in front of a computer are more likely to be obese, which carries inherent health risks.

2. Being in debt

Possessing large amounts of debt can cause physical and mental tolls, an Associated Press poll found. According to the survey, of those with reported "debt stress," 27 percent had ulcers or digestive tract problems, 44 percent had migraines or other headaches, 23 percent had severe depression, and 51 percent had muscle tension, including pain in the lower back. Apparently not all the pain is located in the wallet.

3. Not getting married

Proud singletons may be taken aback by this one: not getting hitched may be detrimental to your health. Data collected by the Australian Bureau of Statistics on age-specific death rates in Australia showed that married people have lower death rates than non-married people in almost all age groups, for both men and women. The reasons for this finding are debatable, but the fact remains: married people live longer.

4. Getting divorced

The National Institute of Mental Health asserts that the most powerful factor of stress-related physical and emotional illness is marital disruption. Researchers have found that, when compared with their similar married counterparts, women who have separated from their husbands for one year or less had poorer immune function in five out of six immunological evaluations. In the broad category of total cancer mortality, men showed an increased risk when they were divorced or separated.

5. Consuming a lot of sugar

Unfortunately, this sweetener invades our diet through sucrose, dextrose, and high-fructose corn syrup. The average American consumes an astounding two to three pounds of sugar each week. Although high sugar intake raises your risk of obesity, simple sugars may cause even more harm than expected. For instance, high amounts of sugar in a person's diet can aggravate asthma, boost susceptibility for heart disease and hypertension, cause mood swings, and hasten the growth of gallstones.

6. Biting your nails

Thumb-sucking and nail-biting are common childhood habits, but only five percent carry the practice into adulthood. Aside from unsightly fingertips, severe nail biting can be a sign of anxiety or compulsive behavior. Biting one's nails can transport infections such as the flu or the common cold. What's more, it can transfer pinworms from the anus region to the mouth. Severe pinworm infestation may be associated with an increased risk for appendicitis. This seemingly innocuous habit is also related to various dental problems, including gingival injury.