If you're a migraine sufferer, you probably go to great lengths to avoid your triggers. But do you really know what they are?

Two small studies were just released at the annual meeting of the American Headache Society one focusing on whether the weather brings on migraine. The other on whether red wine pours on the pain.

First the weather: researchers in Taiwan tracked a group of 66 migraine patients for a year. The scientists looked at their personal headache logs, and found that temperature change was associated with approximately 21 percent of mild headaches, but only 4-point-8 percent of severe ones. Those temperature sensitive patients seemed to be more sensitive to cold dips.

Meanwhile, researchers in Brazil followed migraine patients who reported painful attacks when they drank wine. Participants were asked to drink 4 different types of red wine, a minimum of 4 days apart. They were also instructed to keep detailed headache calendars.

About half of the subjects reported migraines on at least two of the drinking occasions, and only about 12 percent didn't have a single attack. For those who had headaches, Tannat and Malbec wines triggered migraines more often; the theory being the different level of tannin in these red wines might make a difference.

Migraines can be extremely disabling and costly, accounting for more than $20 billion each year in medical expenses and lost work in the United States. If you suffer from debilitating headaches, talk to your doctor; help is available.

I'm Dr. Cindy Haines of HealthDay TV, with the news that doctors are reading; health news that matters to you.