Have a sweet tooth? It could protect you from a stroke, according to a large Swedish study published Tuesday on women chocolate-lovers.

"We followed 33,000 women over the course of 10 years, and we found that those who ate most chocolate had a much lower risk -- 20 percent lower -- of suffering a stroke," said Susanna Larsson, one of three researchers at the Karolinska Institute in Stockholm who carried out the study.

The study, published this week in the Journal of the American College of Cardiology, began in 1997 when the researchers asked 33,372 women in Sweden between the ages of 49 and 83 to fill out a questionnaire on their eating habits.

The women were asked to indicate how often they on average had consumed chocolate and 95 other foods during the previous year.

Over the following decade, a total of about 1,600 strokes were registered in the group.

After taking into account all the known risk factors for stroke, the researchers discovered that the women who ate the least chocolate -- between eight grammes (0.3 ounces) a week and none -- "were the ones who suffered most strokes," Larsson told AFP.

The women who ate the most chocolate -- on average 66 grammes (2.3 ounces) per week -- were the least likely to suffer a stroke, she said.

While the women were not asked to distinguish between light and dark chocolate, she points out that in the 1990s, about 90 percent of all chocolate eaten in Sweden was milk chocolate.

"If we had been able to separate light and dark chocolate we think that the connection would have been clearer with dark, since it's cocoa that is the protective substance," Larsson said.

She said she and her colleagues had found what they had expected to find.

"We weren't really surprised, because our hypothesis was that chocolate would help protect against strokes," she said, pointing out that it had already been shown that "chocolate reduces blood pressure, and high blood pressure is a high risk factor."

Other studies have also shown that antioxidants in chocolate "can reduce oxidation of the bad (low-density lipoprotein) cholesterol, and has been shown to improve insulin resistance," she pointed out.

A few smaller studies have previously hinted that eating chocolate could help protect against strokes, but the Karolinska Institute team's decade-long study of such a large number of test subjects is the first to reach a clear connection.

Larsson said she and her colleagues now planned to check if they could find the same connection in men.

"We expect we will see the same connection," she said.