Older adults with mild cognitive impairment who followed the MIND diet for 12 weeks improved in cognition, nutritional status, quality of life and daily functioning compared with a control group, although researchers cautioned that the small trial does not show the diet can prevent dementia or reverse cognitive decline.
By yourNEWS Media Newsroom
A 12-week randomized trial involving 80 older adults with mild cognitive impairment found that participants assigned to a MIND-style diet showed improvements in several measures of cognitive and everyday functioning compared with people who received no intervention.
Participants who received MIND-based meals and snacks improved in cognitive function, nutritional status, quality of life and daily functioning, according to researchers. A second group that followed the same diet while also completing digital cognitive training showed similar gains and additionally improved in muscle strength.
Researchers cautioned that the findings are preliminary.
The study was relatively small, lasted only three months and involved older adults attending daycare centers. It did not establish that the MIND diet can prevent dementia, cure mild cognitive impairment or permanently reverse age-related changes in memory and thinking.
The results instead add to a growing body of research examining whether dietary patterns rich in plant foods, whole grains, fish and unsaturated fats may be associated with healthier cognitive aging.
The MIND diet — short for Mediterranean-DASH Intervention for Neurodegenerative Delay — combines elements of the Mediterranean diet with the Dietary Approaches to Stop Hypertension, or DASH, diet.
It places particular emphasis on foods researchers have associated with cardiovascular and neurological health, including leafy green vegetables, other vegetables, berries, nuts, beans, whole grains, fish, poultry and olive oil.
It recommends limiting foods such as red meat, butter, cheese, fried foods and sweets.
The 80 participants in the trial were randomly assigned to one of three groups.
One group received MIND-based meals and snacks five days per week.
A second group received the same dietary intervention in addition to structured digital cognitive training intended to exercise thinking skills.
A third group received neither intervention and served as the control.
Researchers measured several outcomes before and after the 12-week study period, including cognition, nutritional status, quality of life, ability to perform daily activities and muscle strength.
Both intervention groups showed improvements in cognition, nutrition, quality of life and daily functioning relative to the control group.
Only the group receiving both the MIND diet and cognitive training showed a significant improvement in muscle strength.
Researchers did not conclude that cognitive training directly increased muscle strength.
The finding could instead reflect broader changes associated with engagement, activity, nutrition or other differences between groups, and the short trial was not designed to determine a biological mechanism.
The cognitive findings are consistent with previous research examining diet and aging.
The MIND eating pattern has previously been associated with slower cognitive decline among older adults, although observational studies cannot prove that the diet itself produces the effect.
Other research has examined related dietary patterns.
One large study involving approximately 29,000 adults in China older than 60 found that people who followed a balanced diet and other healthy lifestyle habits experienced slower age-related memory decline.
The association was also observed among people carrying APOE variants associated with a higher risk of Alzheimer’s disease.
Dietary fiber has emerged as another area of interest.
Long-term studies conducted in Japan and Italy and published in recent years followed participants for periods of roughly 15 to 20 years and reported associations between higher fiber intake and lower risk of Alzheimer’s disease or other forms of dementia.
Those studies, like most nutrition research, cannot prove that fiber alone was responsible for the difference.
People who consume more fiber may also eat more vegetables, fruits, legumes and whole grains, exercise more often or have other health behaviors that contribute to better outcomes.
The new MIND trial is notable because participants were randomly assigned to intervention groups rather than simply observed based on their existing eating habits.
Randomization can reduce some of the differences that complicate observational research.
The study’s short duration and modest sample size, however, limit how much can be concluded.
Twelve weeks is enough time to detect changes in some measures of function and well-being, but it is far too short to determine whether an eating pattern changes the long-term risk of dementia or neurodegenerative disease.
Researchers said larger studies lasting considerably longer will be necessary to determine whether the improvements persist.
The study also leaves unanswered whether similar results would occur among older adults living independently, people with different medical conditions or populations with more advanced cognitive impairment.
The finding involving muscle strength in the combined diet-and-training group adds another dimension to the growing research on the relationship between physical health and cognition.
Separate research has suggested that resistance and strength training may benefit brain health by supporting memory, preserving brain volume and improving cognitive performance in some older adults with mild cognitive impairment.
Those findings have contributed to increasing interest in multidomain interventions that combine nutrition, physical activity, cognitive engagement, sleep and social connection rather than relying on a single strategy.
The MIND diet itself was designed around that broader understanding of brain health.
Many of its recommended foods are also associated with cardiovascular benefits, and vascular health is closely related to cognitive aging because the brain depends on consistent blood flow and healthy blood vessels.
Leafy greens, berries, beans and whole grains also provide vitamins, minerals, antioxidants and fiber that may influence inflammation, metabolic health and cardiovascular risk.
Researchers have not established which individual components of the diet matter most or whether the overall pattern is more important than any single food.
That uncertainty is one reason experts generally describe the diet as a healthy eating pattern rather than a treatment for cognitive disease.
The results also come amid broader research into how lifestyle may influence brain health throughout life.
Some studies have associated diets high in ultra-processed foods with unfavorable measures of brain structure and metabolic health, while healthier dietary patterns have repeatedly been linked with better cardiovascular and cognitive outcomes.
Those associations do not establish direct causation, and nutrition studies are especially vulnerable to confounding factors because eating habits are closely connected with income, education, physical activity, healthcare access and other behaviors.
The randomized design of the 80-person trial helps address some of those concerns, but its limited duration makes it impossible to determine whether the observed improvements represent lasting neurological changes.
Researchers also stressed that mild cognitive impairment can have many causes.
Some people with the condition remain stable for years, some improve and others progress to dementia.
Changes in memory or thinking can also be influenced by medications, sleep disorders, depression, cardiovascular disease, nutritional deficiencies and other treatable conditions.
For that reason, significant cognitive changes should be evaluated by a healthcare professional rather than assumed to be part of normal aging.
The study does not establish that changing diet alone can halt cognitive decline.
What it does show is that, over 12 weeks, older adults assigned to MIND-style meals performed better across several measures than a control group, while those who combined the diet with digital cognitive training also showed improvement in muscle strength.
The findings support continued investigation into whether dietary interventions can play a meaningful role in maintaining function among people already experiencing mild cognitive impairment.
For now, researchers say the results are encouraging but preliminary.
The MIND diet offers a practical framework centered on vegetables, berries, whole grains, nuts, beans, fish, poultry and olive oil while limiting foods higher in saturated fat and added sugar.
Whether that pattern can produce durable protection against dementia remains unanswered, but the latest trial suggests it may improve several aspects of well-being and function over the short term in older adults with mild cognitive impairment.
Explainer Infographic
Comments