Stress

Frayed nerves are a frequent cause of "tension" headaches and may also trigger migraines. Ideas: Take 30 minutes a day just to dream, meditate or otherwise relax.

Diet

Certain foods contain substances that can trigger headache pain. Examples: caffeine, red wine, processed meats, chocolate, cheese, citrus fruits, lentils, snow peas and monosodium glutemate (MSG).

Eye Strain 

Concentrating on one object for a ong time (such as a computer screen) can cause temporary head pain. Suggestions: Take occasional "eye breaks" by looking out a window --- consider an eye exam to see if a vision problem may be a factor.

Sitting

Staying seated for long periods, especially if you are constantly on the phone or hunched over, can tighten muscles and lead to tension headaches. Self-defense: shift position, stretch once an hour, stand during phone conversations and take a lunchtime walk.

Sleep

Too little or, surprisingly, even too much sleep can bring on headaches. Best: control your brain's "clock" by going to bed and getting up at the same time each day - even on weekends.