Certain food combinations, including fish, fruit, and nuts, are linked to a reduced risk of contracting the brain-wasting disease Alzheimer's, according to a study released Monday.

The study published in the online edition of the journal Archives of Neurology, also found a link between decreased Alzheimer's risk and consumption of fewer high-fat dairy products, red meats, organ meats and butter.

Researchers at the Columbia University Medical Center in New York, observed 2,148 adults aged 65 and older who did not have Alzheimer's.

Participants provided information about their diets and were assessed for the development of dementia at year-and-a-half intervals for an average of four years.

During the study, 253 of these test subjects developed the disease, the scientists said.

Among the foods associated with reduced Alzheimer's risk were salad dressing, nuts, fish, tomatoes, poultry, fruits, and dark, leafy green vegetables.

Reducing intake of high-fat dairy, red meat, organ meat and butter also were associated with a reduced Alzheimer's risk.

"Our findings provide support for further exploration of food combination, based dietary behavior for the prevention of this important public health problem," the researchers concluded.

They noted that past scientific literature regarding the impact of individual nutrients or food items on Alzheimer's has been inconsistent, partly because most people combine in their meals a complex array of nutrients and food items that are likely to be "synergistic."