Following Diets to Lower Blood Pressure Protects Women from Dementia

A new study provides increasing evidence that women who follow diets designed to lower blood pressure are less likely to report memory loss and other signs of cognitive decline later in life.

The study, published in the journal Alzheimer's and Dementia, analyzed data from over 5,000 of the more than 14,000 women enrolled in New York University Grossman School of Medicine's long-running Women's Health Study. The study examines how lifestyle factors influence the risk of developing cancer and other chronic conditions.

The investigators analyzed the women's dietary habits between 1985 and 1991, when they were around 49 years old, on average. Then, they followed them for 30 years to see what medical conditions they developed as they aged.

The women are now, on average, 79 years old. Forms they answered as part of the study included six questions about cognitive issues considered precursors to dementia. The questions included things like have you experienced difficulties remembering recent events? Have you had trouble understanding spoken instructions? Have you had trouble remembering how to navigate familiar areas?

One-third of the women reported having more than one of the six cognitive difficulties. Still, those who ate closest to the DASH diet in middle age were 17 percent less likely to report having experienced multiple cognitive difficulties.

DASH stands for Dietary Approaches to Stop Hypertension. The diet emphasizes eating higher levels of plant-based foods rich in potassium, calcium, and magnesium and lower fat, cholesterol, salt, and sugar levels.

"Our data suggest that it is important to start a healthy diet in midlife to prevent cognitive impairment in older age," Yixiao Song, a researcher at the NYU School of Global Public Health and a lead author of the study, said in a statement.

Fen Wu, a senior associate research scientist at NYU School of Medicine and co-author of the study, agreed: "Following the DASH diet may not only prevent high blood pressure, but also cognitive issues."

Next, the authors will test their findings across varying racial and ethnic groups to see if it holds.

The study is important because women currently make up more than two-thirds of those diagnosed with Alzheimer's disease, the most prevalent form of dementia.