Overweight and obese women need to exercise about an hour a day, five days a week, to lose weight and sustain it, a new study has found.

Researchers from the University of Pittsburgh and colleagues tracked 201 overweight and obese women over a two-year period. The participants were randomly assigned to one of four groups based on how much and how intensely they exercised and how many calories they burned

Consumption of as much as two fruit juices a day could increase the risk of diabetes in African-American women by almost a third, a new study suggests.

The study, published in the Archives of Internal Medicine, tracked 43,000 participants in the Black Women's Health Study for a decade to find out how drinking patterns affected diabetes risk. Women who had fruit drinks including Kool- Aid, fruit punch, Snapple and juices were 31 percent more likely to develop type 2 diabetes than those who did not

A medical disaster caused by a likely shortage of medical isotopes looms due to the shutdown of the Chalk River National Research Universal reactor.

Fifty percent of the global supplies of raw materials for medical isotopes are obtained from the Chalk River reactor, which was closed because it failed to meet licensing requirements that seven upgrades be fully operational by Dec. 31, 2005

People exposed to passive smoking, also known as second hand smoking, are at a greater risk of stroke, a new study says. This is also true of a non-smoker married to a smoking partner, respiratory health experts say.

The study, carried out by a Harvard University team, looked at records of more than 16,000 people aged over 50 and their spouses over a period of, on average, slightly more than nine years. The results showed that non-smokers living in the same house as a smoker were at far greater risk of stroke

Google Inc. and four medical schools vie for a share of Wikipedia's patron base with the launch of their respective versions of the popular free online encyclopedia on Wednesday.

Unlike Wikipedia, the search engine company's Google Knol will have bylines and fees for authors as well as ads. Google will not edit entries and readers can rank the usefulness of articles, add comments, and ask questions