One of our biggest stressors is not finances or marriage but the lack of a regular routine. Even simply eating lunch an hour later than usual can spike levels of the stress hormone cortisol and disrupt your body's ideal state. Try to eat, sleep, and exercise at the same time every day, 365 days a year. Watch out for the silent signs stress is making you sick.

Your fruit and veggie selections

By the time produce travels from its source to store shelves, it has lost many of its disease-fighting compounds. Buy fresh veggies locally or when in season. If not, stick to frozen, which is prepared at peak ripeness to lock in nutrients.

Even if you exercise vigorously, spending the rest of your day sitting could affect cholesterol, blood sugar, and blood pressure. Find little ways to get moving all day long, including these sneaky ways to stay fit without working out.

Your heels

You know that stilettos aren't comfy, but the pain they cause is also a sign of inflammation linked to chronic disease. While Dr. Agus doesn't say that heels trigger heart attacks, he does believe that sticking to comfortable shoes can protect your body from inflammation's long-term damage. Can't give up your perfect pair of pumps? Here's how to wear heels and still feel comfortable.

Your nail biting

Nail biting is more than just a bad tendency; it can also wreak havoc on your health. In a small Turkish study, 76 percent of nail-biters tested positive for diarrhea- and vomit-causing bacteria like Escherichia coli, compared to just 26.5 percent of non-biters. Doctors say these little habits hurt your health, too.

Your smoking habit

If the cancer risk alone wasn't a good enough reason to quit this vice, here's one more: Smoking can decrease your immune function, making you more likely to catch the flu, cold, or pneumonia. Don't miss these clear signs you're getting sick.