- The Mediterranean and MIND diets are plant-based eating plans that emphasize vegetables, fruits, beans, nuts, and fish.
- Researchers say people who adhere to these diets appear to have fewer of the tangles and plaques in their brains associated with Alzheimer’s disease.
- Experts say you can adopt a plant-based diet plan by having salads at lunch and dinner as well as eating vegetables and fruits as snacks.
People who ate diets rich in green leafy vegetables as well as fruits, whole grains, olive oil, beans, nuts, and fish had less plaque and tau tangles in their brains than people who did not follow one of these eating patterns, according to a study published today in the online journal Neurology.
Plaque and tau tangles are both found in the brains of people with Alzheimer’s disease.
Researchers analyzed the brains of 581 people who agreed to donate their brains to research when they died.
The participants completed annual questionnaires on how much food they ate in various categories. They lived an average of seven years after the start of the study.
During an autopsy, researchers determined the number of plaques and tau tangles. They also examined the questionnaires and ranked the diet quality of each person.
When analyzed after death, 66% of the participants met the criteria for Alzheimer’s disease.
For people following the Mediterranean diet, there were 11 categories.
Each person scored between 0 and 35 based on their adherence to eating whole grain cereals, fruits, vegetables, legumes, olive oil, fish, and potatoes. They were given low scores for eating red meat, poultry, and full-fat dairy products.
Those with the highest scores had an average of 35 points and those with the lowest had an average score of 26.
There were 15 categories for the MIND diet.
These participants were given one point for each of the 10 brain-healthy food groups and lost a point if they ate foods in the five unhealthy food groups. The healthy food groups included green leafy vegetables, other vegetables, nuts, berries, beans, whole grains, fish, poultry, olive oil, and wine. The unhealthy groups included red meats, butter and margarine, cheese, pastries and sweets, and fried and fast foods.
Those with the highest scores had an average score of 9. Those with the lowest scores had an average of 6.
The participants with the highest scores in the Mediterranean diet had average plaque and tau tangles, similar to someone 18 years younger than those with the lowest scores.
Those with the highest scores in the MIND diet group had plaques and tau tangles similiar to people 12 years younger than the participants with the lowest scores.
For every increase of one point, the researchers found the participants had typical plaque amounts equal to people 4.25 years younger.
The scientists also looked at how certain foods affected brain health. For example, people who had seven or more servings per week of green leafy vegetables had brain health equal to those 19 years younger than those who ate the fewest.
“Both the Mediterranean and MIND diets are considered plant-forward, meaning most of your plate comes from fruit, veggies, grains, nuts, and healthy fats. Protein sources from meat are still a part of the meal but not the largest portion,” said Caroline Thomason, RD, a Virginia-based dietitian who helps women stop dieting and find confidence with food.
“There are a few key players regarding healthy aging and the MIND diet,” Thomason told Healthline. “Leafy greens, nuts, berries, beans, fish, olive oil, poultry, whole grains, and wine all were associated with a decreased level of plaque in their brain that leads to Alzheimer’s disease and dementia.”
Although this study focused on brain health, experts say choosing the Mediterranean or MIND diet can also improve your heart and overall health.
“Foods that support heart health are also essential to brain health,” said Molly Rapozo, RDN, a registered dietician, nutritionist, and senior nutrition and health educator at Pacific Neuroscience Institute in California.
“Saturated fats and refined carbohydrates pose similar risks to the heart and brain. In contrast, nutrient-dense plant foods and monounsaturated fats may reduce oxidative damage and inflammation while improving blood vessel function,” Rapozo told Healthline.
It’s important to note that this study was observational and did not establish cause and effect.
It’s sometimes difficult to know where to start when you want to adopt healthier eating habits.
“Get prepared and be clear on what you’re doing: What is the goal?” said Tiffany Caplan, DC, a certified functional medicine provider at the Central Coast Center for Integrative Health in California. “What are you currently doing? What is working or not working for you?”
“I highly encourage everyone to start every diet with an elimination/reintroduction process which will allow them to personalize their dietary approach to what works best for their body,” Caplan told Healhline. “Just because a food is on the ‘good’ list of foods to eat doesn’t mean your body can necessarily tolerate it. For example, someone with rheumatoid arthritis may not tolerate whole grains or nightshade vegetables, or someone without a gallbladder may have trouble incorporating too much healthy fat into their diet. Every dietary approach should be tailored to the individual to work best for their body and individual needs or intolerances.”
“Incorporate more whole plant foods into your diet. If leafy greens aren’t a staple already, this could be a great place to start,” Rapozo said. “There are many ways to include leafy greens.”
Here are some of her other ideas:
- Start at breakfast with eggs and sautéed greens, or add a handful of spinach on your morning smoothie.
- Have an entrée salad for lunch.
- Enjoy a side salad with dinner.
- Add prewashed and ready-to-eat greens to sandwiches, wraps, and tacos.
- Hearty greens like baby kale last longer in the refrigerator and may be incorporated into mixed dishes like soups, stews, and casseroles.
- Try a new leafy green or incorporate greens in a new way, such as baking escarole with salmon on a sheet tray.
Anne Danahy, RD, a registered dietitian and author of “The Mediterranean Diet Cookbook for Two,” focuses on adding nutrient-dense foods to your diet.
“Both the Mediterranean and MIND diets are heavy in fruits and vegetables, and the research on the health benefits of leafy green vegetables and berries is compelling — not only for reducing dementia risk but chronic disease risk in general. A great place to start is adding a few extra servings of leafy greens and berries each week,” Danahy told Healthline.
“Diets can be daunting and overwhelming. In general, I emphasize hydration and balance depending on your lifestyle,” said Dr. Shae Datta, a neurologist at NYU Langone Health.
“Eating as many whole foods as possible enables us to get the proper nutrients from our food. Both diets benefit heart and brain health,” Datta told Healthline. “The MIND diet typically showed less plaque formation and brain age was younger by 12 years. The MIND diet also prioritizes berries over other fruits and recommends one or more servings of fish per week.”