A woman preparing food in a kitchen.Share on Pinterest
New research suggests that women who follow a heart-healthy diet during midlife may have a lower risk of cognitive decline as they age. Adam Kaz/Getty Images
  • A heart-healthy diet was linked with less risk for cognitive decline during aging.
  • Additionally, better compliance with the diet yielded greater protection.
  • Heart-healthy diets have positive effects on blood pressure and brain cell health.
  • They include beneficial foods while reducing those linked to cardiovascular risk.
  • People on a heart-healthy diet also often adopt other lifestyle changes.

The DASH diet is a way of eating designed to help people lower their blood pressure.

It has also been shown to reduce people’s risk for cardiovascular disease and stroke.

Now, according to a new study published in the journal Alzheimer’s & Dementia, it could also be helpful in preventing cognitive decline in later life.

The study found that women who followed the heart-healthy plan during midlife were less likely to show signs of cognitive decline as they grew older.

Additionally, the more closely they followed the diet, the less likely they were to experience these issues.

The study included data from 5,116 women out of over 14,000 who were enrolled in the NYU Women’s Health Study.

The women included in the analysis were, on average, 46.3 years old when they entered the study.

To see what sort of diet the women consumed, the researchers had them fill out food frequency questionnaires.

The collected data was next scored on how closely it matched the DASH diet.

The women were then followed for the next three decades; and, toward the end of that period, were asked to report any sort of cognitive issues that they experienced.

To evaluate the women’s reports, the researchers asked them six questions known to be indicative of mild cognitive impairment that can lead to later dementia.

For example, they were asked about such things as whether they had had problems finding their way on familiar streets or difficulty in remembering recent events.

One-third of the women said they had more than one of the six types of cognitive complaints that they were asked about.

However, those who had the strongest adherence to the DASH diet had a 17% lower risk of reporting multiple complaints.

According to Kelsey Costa, M.S., RDN, a registered dietitian and nutrition consultant for the National Coalition on Healthcare, heart-healthy diets like the DASH diet are rich in certain nutrients and bioactive compounds that are commonly found in vegetables, fruits, legumes, nuts, and seeds.

“These components possess anti-inflammatory and antioxidant properties,” she explained, “potentially reducing brain oxidative stress while promoting neurogenesis (nerve cell formation) and neuronal connectivity, contributing to our brain’s overall health and functionality.”

The DASH diet also reduces high blood pressure, she noted. Elevated blood pressure is a known risk factor for cognitive decline.

Costa additionally noted the benefits of what a heart-healthy diet doesn’t include.

“By limiting the consumption of red and processed meats, along with sugary foods,” she stated, “a heart-healthy diet can potentially mitigate the damaging impacts of high fat and sugar on triggering brain inflammation and the production of amyloid-beta proteins, which are linked with Alzheimer’s disease.”

Finally, she said that a heart-healthy diet can create positive changes in the gut microbiome. This might help stave off cognitive decline as we age by reducing inflammation and supporting the production of neurotransmitters that affect mood and cognitive function.

Dr. John Higgins, a cardiologist with UTHealth Houston, said that, in addition to the DASH diet, the two other main heart-healthy diets are the Mediterranean diet and a plant-based diet.

“There is a lot of overlap between these diets,” he noted.

“These all are associated with improved blood pressure,” explained Higgins, adding that they can generally produce a reduction in systolic blood pressure (the top number of your reading) of 11.5 mm Hg in people with hypertension, and 7.1 mm Hg in participants without hypertension.

Higgins said these diets also share the following core aspects:

  • They contain monounsaturated fat or polyunsaturated fat from sources like extra-virgin olive oil or salmon.
  • They provide reduced amounts of cholesterol and sodium.
  • They are high in potassium-rich foods like spinach, yams, avocado, and banana.
  • They provide plenty of fresh vegetables, legumes, nuts, whole grains, and lean protein.

Most people following a heart-healthy diet also follow other healthy lifestyle habits …,” added Higgins, including the following:

  • Engaging in physical activity of at least 150 minutes per week
  • Socializing at least weekly, preferably in person
  • Losing weight to reach a normal BMI below 25
  • Bringing blood lipids, blood pressure, and blood sugar into a normal range
  • Quitting smoking or never starting, including avoiding secondhand smoke
  • Getting 7-9 hours of sleep per night

Women who ate a diet most closely resembling the DASH diet when they were middle-aged reported fewer symptoms of cognitive decline as they grew older.

Heart-healthy diets like the DASH diet, the Mediterranean diet, and plant-based diets appear to provide several potential benefits for brain health, including reduced inflammation, lower blood pressure, and a healthier gut microbiome.

It is recommended that people adopt other heart-healthy lifestyle habits along with making good dietary choices. These include getting more physical exercise; socializing regularly; normalizing your weight, lipids, blood pressure, and blood sugar; quitting smoking; and getting adequate sleep.