A diet rich in leafy green vegetables, whole grains, nuts and fish has been linked to fewer signs of Alzheimer’s disease, researchers have found.
A study of older people found that those who followed the MIND and Mediterranean diet had fewer amyloid plaques and tau tangles in their brain.
While researchers say they have yet to identify a ‘cause and effect’ relationship, they say their findings show that eating more of certain foods can boost brain health.
For those following a Mediterranean diet, the amount of plaque and tangle in their brain was similar to being 18 years younger in comparison to participants who scored lowest for the amount of brain-healthy food they ate.
The figure for people following the MIND diet was 12 years younger.
What is a Mediterranean diet?
A Mediterranean diet comprises of foods from countries that border the Mediterranean Sea – places like Greece, Cyprus, Italy and Spain.
The diet contains olive oil, dairy products, fish, poultry, fruits, vegetables, whole grains, legumes, nuts, and seeds.
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What is the MIND diet?
The MIND diet is also known as the Mediterranean-DASH Intervention for Neurodegenerative Delay.
While not many people have heard of it, the approach combines the DASH diet, or Dietary Approaches to Stop Hypertension diet, with the Mediterranean diet.
Notably, the MIND diet encourages leafy green vegetables, berries, nuts, and whole grains.
Less plaque associated with healthier habits
Study author Dr Puja Agarwal, PhD, from RUSH University in Chicago, said: “These results are exciting – improvement in people’s diets in just one area, such as eating more than six servings of green leafy vegetables per week, or not eating fried foods – was associated with fewer amyloid plaques in the brain similar to being about four years younger.
“While our research doesn’t prove that a healthy diet resulted in fewer brain deposits of amyloid plaques, also known as an indicator of Alzheimer’s disease, we know there is a relationship and following the MIND and Mediterranean diets may be one way that people can improve their brain health and protect cognition as they age.”
The two diets have similarities, but the Mediterranean diet promotes eating vegetables, fruit and at least three portions of fish each week while the MIND diet recommends leafy green vegetable such as kale and spinach and other vegetables, along with berries and at least one serving of fish a week.
Both diets recommend a small quantity of wine.
The study involved 581 older participants who agreed to donate their brains to research at death.
Just before death, 39% had been diagnosed with dementia and just after death, researchers found that 66% reached the criteria for Alzheimer’s disease. At the start of the study, participants began completing yearly questionnaires about the type of food they eat.
Autopsies looked at the amount of plaque and tau tangles in each participants’ brain, while the food questionnaires were analysed and each person’s diet quality was ranked.
Each person was then given a score as to how much they consumed certain types of food, including legumes, olive oil and vegetables. Lower scores were given for things like red milk and full-fat dairy foods.
Notable findings
One of the most notable findings was among those who ate the most amount of green leafy vegetables, with researchers noting that the amount of plaque found in their brains corresponded to being almost 19 years younger than people who ate much less.
Dr Agarwal said: “Our finding that eating more green leafy vegetables is in itself associated with fewer signs of Alzheimer’s disease in the brain is intriguing enough for people to consider adding more of these vegetables to their diet. Future studies are needed to establish our findings further.”
The study adds to a growing body of research demonstrating the potential benefits of a real food approach to eating.
A real food approach to eating focuses on natural, unprocessed or minimally processed foods while minimising processed or ultra processed foods.
Read the study in the journal Neurology.
