Mediterranean and MIND diets reduce signs of Alzheimer’s disease in brain tissue, study finds

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People who ate foods from the brain-focused Mediterranean plant-based and MIND diets had fewer hallmark signs of Alzheimer’s disease — sticky plaques of beta-amyloid and tau tangles in the brain — during autopsy, according to a new study.

The MIND diet is short for Mediterranean-DASH Diet Intervention for Neurodegenerative Delay.

In fact, people who followed either diet most closely had “nearly a 40% lower chance” of having enough plaques and tangles in brain tissue to be diagnosed with the disease. Alzheimer’s, according to the study.

“People who scored highest for adherence to the Mediterranean diet had average amounts of plaque and tangles in their brains similar to being 18 years younger than people who scored highest. low,” according to a statement from the study. “Researchers also found that people who had the highest scores for adhering to the MIND diet had similar mean amounts of plaque and tangles 12 years less than those who had the lowest scores.”

That’s not all. Adding just one food category to either diet—such as eating the recommended amounts of vegetables or fruit—reduced amyloid buildup in the brain to levels similar to the one about four years younger, according to the study.

“Making a simple dietary change, like adding more green vegetables, berries, whole grains, olive oil, and fish, can actually delay the onset of Alzheimer’s disease or lower your risk of dementia. when you get older,” said study author Puja Agarwal. , assistant professor of internal medicine at Rush University Medical Center in Chicago.

People benefit from eating leafy green vegetables.

The most benefit comes from leafy greens, she said. However, adding more berries, whole grains and other healthy diet-recommended foods also helped, she said.

“While this study does not definitively prove that it is possible to slow brain aging through food choices, the data is compelling enough for me to add green leafy vegetables to most of my meals and to suggest the diet Mediterranean style to my at-risk patients,” said Alzheimer’s disease researcher Dr. Richard Isaacson, a preventive neurologist at the Florida Institute for Neurodegenerative Diseases. He was not involved in the new study.

“Of course, the Mediterranean diet is also heart-healthy…reducing the risk of stroke and neurovascular damage which can also increase the risk of Alzheimer’s disease pathology,” said Rudy Tanzi, professor of neurology at Harvard Medical School, who was not involved in the study.

“What’s good for the heart is good for the brain,” said Tanzi, who is also director of the Genetics and Aging Research Unit at Massachusetts General Hospital in Boston.

The Mediterranean diet favors plant-based cuisine. The majority of every meal should consist of fruits and vegetables, whole grains, beans and seeds, and some nuts. The focus is on extra virgin olive oil. Butter and other fats are eaten rarely, if at all. Sweets and products made from refined sugar or flour are rare.

Meat can make a rare appearance, but usually only to flavor a dish. Instead, meals may include eggs, dairy, and poultry, but in much smaller portions than in the traditional Western diet. However, fish, which is packed with brain-boosting omega-3s, is a staple.

The Mediterranean diet, which has won top honors as the best diet for years, is backed by an impressive list of scientific knowledge. Studies have shown that this way of eating can prevent cognitive decline, but also help the heart, reduce diabetes, prevent bone loss, promote weight loss and more.

The MIND diet was developed in 2015 by Rush researchers interested in taking the Mediterranean diet to the next level by focusing it on brain health. Instead of providing a blanket statement — eat more vegetables and fruits — like the Mediterranean diet does, the MIND diet recommends specific amounts of brain-healthy foods, Agarwal said.

For example, leafy greens, the darker the better, should be eaten every day of the week on the MIND diet. These include arugula, collard greens, dandelion greens, endive, grape leaves, kale, mustard greens, romaine lettuce, spinach, Swiss chard and turnip greens .

Berries are also stressed compared to other fruits in the MIND diet. Blackberries, blueberries, raspberries or strawberries should be eaten at least five days a week.

A 2017 study of nearly 6,000 healthy older Americans, with an average age of 68, found that those who followed the Mediterranean diet or MIND reduced their risk of dementia by a third.

The study, published Wednesday in the journal Neurology, examined the brains of 581 people who each donated their bodies to Rush University’s Memory and Aging Project. The project, which began in 1997, has been collecting information on participants’ annual diets since 2004, Agarwal said.

The current study analyzed diet data from 2014, for an average of six to seven years, and then compared that information with the number of plaques and tangles in each person’s brain at autopsy.

Examining brain tissue to determine the specific level of dementia markers was a unique part of the study, Agarwal said: “Previous studies of dementia risk have focused more on clinical outcome – cognitive performance over time. time – but our study actually examines the characteristics of disease in the brain after death.

People who ate larger amounts of pastries, sweets, fried foods and fast food had significantly higher levels of plaques and tangles in their brain tissue, the study found.

Which food was most helpful in reducing buildup? Green leafy vegetables, which are packed with bioactives, chemicals found in food that reduce inflammation and promote health. Examples of bioactive compounds include vitamins, minerals, flavonoids (antioxidants) and carotenoids (pigments in the skin of vegetables).

The brain tissue of people who ate the most leafy greens looked almost 19 years younger in terms of plaque buildup compared to those who ate one serving or less per week, according to a statement from the agency. ‘study.

“The combination of different nutrients and bioactives in green leafy vegetables makes them unique,” ​​Agarwal said. “They are very high in many bioactives, flavonoids and lutein, which are important for brain health.”

There are different hypotheses as to why lutein might help with overall brain integrity,” she added, “such as reducing oxidative stress and inflammation.”

The most impressive impact of the diets was on beta-amyloid accumulation, not tangles, and “the inverse association with beta-amyloid load was stronger for the Mediterranean diet than for the MIND diet” , says the study.

There was some reduction in tau tangles, the other key marker for Alzheimer’s disease, but it wasn’t as robust as that of amyloid, Agarwal said. However, Agarwai and his team conducted another study which found that eating berries, a key part of the MIND diet, was helpful in reducing tangles in the brain.

“We still have to really sort out what exactly is going on,” she said. “But overall, these diets are rich in essential nutrients and bioactives that reduce overall inflammation and oxidative stress in the brain and likely lead to less amyloid plaque buildup and tangles.”

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