Coffee May Have Health Perks, Research Shows

(CBS) -- Millions of Americans jump-start their day with a cup of coffee.  And it turns out, that may be a good thing.

CBS 2's Mary Kay Kleist shows us seven ways coffee may help your health.

"I smell the coffee and I'm like, 'Ohh.' You know, it just calls you," says coffee drinker Judith Meza Vazquez.

And research shows answering that call may serve up a lot of potential health benefits:

-- In one study, people who drank 4 to 5 cups of coffee a day lived longer than those who only drank a cup or less.

-- Another found the caffeine in coffee helps ease headache pain by narrowing dilated blood vessels in the brain.

-- A third study found that the compound in coffee responsible for its aroma and bitter taste can prevent cavities.

Coffee drinker Cady Sanders says she thinks coffee definitely makes her mind sharper.

"Absolutely, and I can definitely tell if I haven't had my coffee in the morning," she says.

Want to catch a mistake before you send that important memo? Have a cup of coffee.  According to researchers, it takes 200 mg of caffeine a day to make you a better proof-reader.  That's equal to a "tall" at Starbucks.

"Definitely. There's actually an improvement in attention, in working memory, all of those kinds of things," says clinical nutritionist Christine Tangney of Rush University Medical Center.

Drinking coffee may also reduce the risk of several types of cancer, including colon, liver, pancreatic and basal cell carcinoma.

Meanwhile, there's some evidence caffeine helps asthma sufferers breathe easier by relaxing airway muscles.

And can coffee really boost your mood? Maybe.

"Oh yes. I think there's some good data, especially among the elderly folks, that it does improve mood," Dr. Tangney says.

So, how much should you drink?

Tangney says one to three cups is "probably the most optimal," based on the research.