Genetics, head injury and poor nutrition have all been linked to dementia. Scientists are now adding both heavy drinking and abstaining from alcohol to the list, a report said.

Researchers from the French National Institute of Health and Medical Research based in France and the United Kingdom observed more than 9,000 people, 35 to 55, to determine the relationship between midlife alcohol consumption and risk of dementia into early old age.

They found both abstinence in midlife and drinking more than 14 units of alcohol a week were associated with higher risk of dementia, compared to drinking 1 to 14 units weekly. In fact, they discovered that heavy drinkers who increase their consumption by 7 units a week may have a 17 percent increase in dementia risk. A unit is approximately 8 grams of alcohol.

The findings "strengthen the evidence that excessive alcohol consumption is a risk factor for dementia," the authors said. They said it "should not motivate people who do not drink to start drinking given the known detrimental effects of alcohol consumption."

Cauliflower, kale may cut breast cancer risk

Eating substantial amounts of fruits and vegetables may lower the risk for breast cancer, a study found, and some kinds may be more effective than others.

Researchers used questionnaires to examine the association of diet with the risk of invasive breast cancer in 182,145 women, who were followed for an average of 24 years.

The scientists found that compared with having less than 2½ servings (about one cup) of fruits and vegetables a day, having 5½ servings or more was associated with an 11 percent lower breast cancer risk. The researchers found that cruciferous vegetables like cauliflower, Brussels sprouts and kale were especially strongly associated with reduced risk, as were yellow or orange vegetables including carrots, winter squash, yams and sweet potatoes.