A healthy diet not only keeps you physically but also mentally fit. But what does this actually entail? Scientists investigated this in a new study, which is now published in the journal “Jama Neurology“ appeared. The international team, including scientists from Harvard University, compared six eating habits.

They found that the so-called Dash diet reduces the risk of mental decline and improves mental processes such as attention or memory.

This is how the 6 diets differ

The researchers evaluated data from almost 160,000 test subjects from three previous studies. They focused on information about the following six eating habits:

1. AHEI Index (Alternative Healthy Eating Index): This diet was developed at Harvard and aims to prevent chronic diseases. It contains lots of fruits and vegetables, whole grains, nuts and healthy fatty acids.
2. Dash diet (Dietary Approaches to Stop Hypertension): This scientifically based diet is intended to counteract high blood pressure. It consists of foods low in cholesterol and fat and relies on lots of fruit and vegetables and little salt.
3. Healthful Plant-Based Diet Index (hPDI): This is a plant-based points system. There is a positive score for consuming plant-based foods and a negative score for consuming animal products.
4. Planetary Health Diet Index (PHDI): This scientific nutritional concept is intended to protect not only health but also the environment. The diet is very plant-based and low in meat. It includes higher amounts of vegetables, legumes and fruit.
5. rEDIH (reversed empirical dietary indices for hyperinsulinemia) and
6. rEDIP (reversed empirical dietary indices for inflammatory patterns): Both nutritional indices assess the risk to which foods increase insulin levels and promote chronic inflammation.

Dash diet improves brain performance

To analyze how these six diets affect brain performance, the scientists had the test subjects fill out questionnaires and complete tests.

They concluded that strict adherence to the Dash diet was the best way to slow mental decline. This effect was particularly evident between the ages of 45 and 54. Additionally, the Dash diet improved cognition the most of all diets.

In addition, scientists found that certain foods such as

Be careful when drinking wine

The results help researchers understand why the Dash diet has a positive effect on brain performance, said lead author Kjetil Bjornevik, assistant professor in the departments of nutrition and epidemiology at the Harvard TH Chan School of Public Health, “Medical News Today”.

“Vegetables and fish were consistently linked to better outcomes, whereas red and processed meats, fried potatoes and sugary drinks were associated with worse outcomes,” says Bjornevik.

Dash diet is good for metabolism

The Dash diet triggers numerous functional processes in the organism that have positive effects on health. Internist Dung Trinh, who was not involved in the study, explains this in an interview with “Medical News Today”. This diet most directly targets the physiological systems closely linked to brain health:

• blood pressure control,
• vascular function,
• Metabolic Health
• and inflammation.

“The brain is highly dependent on healthy blood vessels and stable metabolic signals,” he said. Dash emphasizes vegetables, fruits, whole grains, legumes and limits sodium and red meat consumption. According to Trinh, these aspects can improve risk factors for cardiovascular diseases such as high blood pressure and obesity, as well as reduce inflammation.

The fact that the Dash diet improves brain performance fits with the idea that blood vessels and metabolism could be important drivers of mental aging, says Trinh.

“You don’t need a perfect diet.”

“The study results also reinforce what I always tell my patients: They don’t need a ‘perfect’ or exotic diet – consistent, practical improvements in overall eating habits seem to make the difference, especially in midlife,” he added.

The results are not proof of a causal connection, says Trinh. This means the study couldn’t show that the Dash diet is actually the cause of the improved brain performance. Nevertheless, the results would be in line with previous findings on cardiovascular and metabolic health.

This is how the Dash diet fits into your everyday life

But how can you best incorporate the Dash diet into your own diet? The US National Heart, Lung and Blood Institute recommends:

• Whole grain products: 7-8 servings per day. One serving is equivalent to a slice of bread or a small bowl of cereal.
• Vegetables: 4-5 servings per day. One serving is equal to half a cup of cooked vegetables.
• Fruit: 4-5 servings per day. One serving is equivalent to one medium-sized apple.
• low-fat dairy products: 2-3 servings per day. One serving corresponds to a cup of yogurt or 200-250 ml of milk.
• lean meat: maximum 2 servings per day. One serving is 80-100 g.
• Nuts, seeds, beans: 4-5 servings per week. One serving is equivalent to 40g of nuts, a tablespoon of seeds or half a cup of uncooked beans.
• Fats and oils: 2-3 servings per day. One serving is equivalent to one teaspoon of margarine, one teaspoon of oil or two tablespoons of salad dressing.
• Sweets and sugary drinks: 5 servings per week. One serving is equivalent to one tablespoon of sugar or 220-250 ml of lemonade.
• Salt: 1.5 to 2.3 grams per day. This corresponds to about half a teaspoon.

The portion information refers to a person with a daily requirement of 2000 calories.

If you want to try the Dash diet, you should change your diet slowly. The large amounts of fruit and vegetables are certainly unusual for many people. Add one, then two extra portions of fruit and vegetables to your lunch and dinner to gradually increase the amount.

Also, from now on, only use half as much butter and margarine as usual. And choose fruit or nuts instead of dessert or a high-calorie snack.