- A healthy diet has been linked to a reduced risk of many health problems, including heart disease and some cancers.
- New research provides further evidence that a varied, plant-rich diet may reduce the risk of cognitive decline and dementia later in life.
- The results show that an unhealthy diet is strongly associated with poorer cognitive abilities, but a high-quality diet during youth and middle age helps maintain brain health as you age.
- Adopting healthy eating habits at any age will improve your chances of staying mentally sharp as you age.
There is strong evidence that a diet rich in plants and low in salt, saturated fats and processed foods is beneficial for overall health. A healthy diet can reduce the risk of cardiovascular disease, diabetes and cancer.
Today, research presented at NUTRITION 2024, the annual meeting of the American Society for Nutrition, provided new evidence that healthy eating throughout life is essential for maintaining cognitive function as we age.
The study suggests that the earlier people adopt healthy eating habits, the more likely they are to remain mentally alert into old age.
The results have not yet been published in a peer-reviewed scientific journal.
Kelsey Costa, a registered dietitian and scientific communications manager at Examine, said: Today’s Medical News:
“This study adds to a growing body of evidence suggesting a strong link between diet and cognitive health, highlighting the importance of food choices in maintaining brain function as we age. The key novelty of the study is that it tracked cognition as well as self-reported diet across the lifespan, which is one of the major contributions of the research.”
The study collected data from 3,059 people over a period of seven decades. All participants were born in March 1946 and were enrolled as children in the Medical Research Council’s National Survey of Health and Development in the United Kingdom.
For more than 75 years, participants in this survey have completed questionnaires and tests about diet, cognition, general health and other factors.
For this study, researchers assessed participants’ dietary intake at five time points between the ages of 4 and 63, using recalls and food diaries. They also measured their cognitive abilities at seven time points between the ages of 8 and 69.
They then used group-based trajectory modeling to study the relationship between diet and cognition.
Scott Kaiser, MD, a board-certified geriatrician and director of geriatric cognitive health at the Pacific Neuroscience Institute in Santa Monica, Calif., said: MNT:
“While this study, and other related seminal studies in this area, are not designed to specifically establish a cause-and-effect relationship, there are many clear causal pathways and plausible biological mechanisms that support the likelihood that various diets and nutritional factors may either protect our brain health or accelerate cognitive decline and impact our mental well-being.”
Researchers used the U.S. Department of Agriculture’s Health and Nutrition Service’s 2020 Healthy Eating Index (HEI) to assess participants’ diet quality.
In this index, higher intakes of foods such as fruits and vegetables, whole grains, protein, dairy, and seafood increase scores, while higher intakes of refined grains, sugar, sodium, and saturated fat lower scores.
The researchers found a strong association between diet quality over time and cognitive trajectory.
Participants who retained high cognitive abilities into old age tended to eat more foods that scored high on the index, such as vegetables, fruits, legumes and whole grains, and less added sugars, refined grains and sodium, foods that lowered HEI scores.
According to the study abstract, 47% of participants who ate the poorest quality diet were in the lowest cognitive trajectory, and only 7% were in the highest cognitive trajectory. Conversely, 48% of participants who ate the highest quality diet were in the highest cognitive trajectory (8% were in the lowest cognitive trajectory).
Although all participants tended to adopt healthier diets as adults, differences in diet quality during childhood influenced later eating habits, as noted by Kelly Cara, Ph.D., senior research scientist at the Friedman School of Nutrition Science and Policy at Tufts University:
“This suggests that dietary intakes during early childhood may influence our dietary decisions later in life, and the cumulative effects of diet over time are linked to progression of our overall cognitive abilities,” she said in a press release.
Costa agrees, but points out that improving your diet later in life can still have a beneficial effect.
“The reported results … suggest that changes made to adopt a healthier diet up to middle age are well correlated with later cognitive outcomes,” Costa said. “This adds a glimmer of hope that the effects of poor early eating can be at least somewhat reversed.”
Diets that have been shown to have health benefits include high intakes of fruits, vegetables, and whole grains, combined with low intakes of sugars, saturated fats, and processed foods. These include the Mediterranean diet,
“A diet rich in antioxidants and anti-inflammatory components, such as fruits, nuts, vegetables, dietary fiber and omega-3s, may help reduce age-related cognitive decline and reduce the risk of neurodegenerative diseases,” Costa said.
“These nutrients protect brain cells from damage related to oxidative stress, support brain structure and function, and maintain a healthy vascular system, which helps promote healthy blood flow to the brain,” she added.
Dr. Kaiser explained the MIND diet to MNT:
“A combination of the Mediterranean and Diet to Stop Hypertension (DASH) diets, the Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND) diet has been shown to slow brain aging by about
All of these diets provide a high intake of
Polyphenols are antioxidants that fight cellular damage and have anti-inflammatory and
Costa advised the following dietary recommendations:
“Brain-healthy foods typically include green leafy vegetables, berries, whole grains, nuts, seeds, beans, seafood, poultry, and olive oil. In contrast, red meat, cheese, butter, refined grains, sweets, baked goods, and fried or fast foods are considered less optimal for brain health. However, a healthy diet is not just about specific foods; it is also about the overall balance of nutrients and calories consumed.
Ultimately, adopting a healthy diet rich in brain-boosting foods can help maintain mental alertness and overall vascular health, promoting a sharper mind well into old age.”