Heart-healthy diets, such as the Mediterranean diet or the Dietary Approaches to Stop Hypertension (DASH) diet, emphasize a balanced consumption of fruits, vegetables, whole grains, lean meats, and healthy fats while minimizing saturated and trans fats, added sweets, and sodium. A new study indicates that women who followed blood pressure-lowering diets during their middle years were roughly 17% less likely to report memory loss and other indicators of cognitive decline decades later.
The new findings, led by researchers from NYU Grossman School of Medicine, suggest that adopting the Dietary Approaches to Stop Hypertension, or DASH diet, in midlife may improve cognitive function later in life for women, who account for more than two-thirds of those diagnosed with Alzheimer’s disease, the most common form of dementia.
The findings, which were published online in the journal Alzheimer’s & Dementia, have implications for the 6.5 million Americans over the age of 65 who will be diagnosed with Alzheimer’s disease in 2022. By 2060, that figure is predicted to more than double.
Subjective complaints about daily cognitive performance are early predictors of more serious neurocognitive disorders such as Alzheimer’s. With more than 30 years follow-up, we found that the stronger the adherence to a DASH diet in midlife, the less likely women are to report cognitive issues much later in life.
Yu Chen
“Subjective complaints about daily cognitive performance are early predictors of more serious neurocognitive disorders such as Alzheimer’s,” said Yu Chen, PhD, MPH, a professor in the Department of Population Health and the study’s principal author. “With more than 30 years follow-up, we found that the stronger the adherence to a DASH diet in midlife, the less likely women are to report cognitive issues much later in life.”
The DASH diet emphasizes plant-based foods rich in potassium, calcium, and magnesium while limiting saturated fat, cholesterol, sodium, and sugar. Long-standing research indicates that high blood pressure, particularly in middle age, is a risk factor for cognitive decline and dementia.
How the Study was Conducted
The researchers examined data from 5,116 of the more than 14,000 women who participated in the NYU Women’s Health Study, one of the longest-running studies of its kind that looks at the impact of lifestyle and other factors on the development of the most common cancers in women, as well as other chronic conditions.
The researchers used questionnaires to ask study participants about their diets between 1985 and 1991, when the subjects were, on average, 49 years old. The subjects were monitored for more than 30 years (with an average age of 79) before being asked to disclose any cognitive concerns. Participants who did not return surveys were called.
Self-reported cognitive complaints were assessed using six validated standard questions that are indicative of later mild cognitive impairment, which leads to dementia. These questions were about difficulties in remembering recent events or shopping lists, understanding spoken instructions or group conversation, or navigating familiar streets.
Three-thirds of women reported having more than one of the six cognitive symptoms. Women who followed the DASH diet the most carefully had a 17 percent lower risk of having numerous cognitive problems.
“Our findings suggest that it is critical to begin a healthy diet in midlife to prevent cognitive impairment in later life,” said Yixiao Song, the study’s lead author. “Following the DASH diet may not only prevent high blood pressure but also cognitive issues,” stated Fen Wu, Ph.D., senior associate research scientist and study co-author.
Future research across numerous racial and ethnic groups is needed, according to the researchers, to determine the generalizability of the findings.
