WASHINGTON: A new study has revealed that a daily aspirin can help lower the risk of heart attack and clot-related strokes.

The new study has revealed why millions of people opt to take a daily low-dose aspirin and also how this therapy seems to work a bit differently for women and men.

Aspirin reduces the clumping action of platelets, the blood's clotting cells. Clotting helps a cut or wound stop bleeding. But clots also form within blood vessels that supply the heart and brain. If the vessels are already narrowed from a build-up of fatty deposits, a blood clot can quickly block an artery, causing a heart attack or stroke.

Previous studies on aspirin therapy only involved men. New studies confirm that women may benefit from aspirin therapy, too, but not exactly the way men benefit.

Recent studies identified the following differences and similarities between the sexes and showed that aspirin:

- Helps prevent a first stroke for women. There's no risk reduction for men.
- Helps prevent a first heart attack for women over age 65 and for all men.
- Helps prevent a second heart attack for men and women, regardless of age.

However, the study recommends that people should consult their doctor before starting an aspirin a day. Regular aspirin use increases the risk of stomach ulcers or a bleeding (hemorrhagic) stroke.

The current studies have suggested that women who are at high risk of heart disease should be on daily aspirin therapy. However, people should weigh the benefits and risks with their doctor.

The study is published in the November issue of Mayo Clinic Women's HealthSource.