Simple method of protecting the brain from the harm of fatty food revealed

Scientists: Fruits and Vegetables Protect the Brain from Harmful Effects of Fatty Foods

A diet rich in fruits and vegetables can become a real shield for the brain against the negative impact of fatty foods. Researchers came to this intriguing conclusion while observing mice on a "Western" diet. It turned out that the rodents maintained their memory in good condition if their diet was supplemented with a special plant mixture. The research results were published in the authoritative scientific journal Nutritional Neuroscience.

The modern world is facing two parallel epidemics - a rapid increase in obesity and an increase in cognitive impairments among the elderly. Scientists have long suspected that excess weight is a risk factor for developing dementia. One of the main reasons cited is the high consumption of calorie-dense food with high saturated fat content, which enhances oxidative stress - a dangerous imbalance between free radicals and the body's antioxidant defenses that gradually destroys tissues, including neural ones.

A research group led by Weimin Guo decided to find out whether a complex of plant products could neutralize these negative effects.

During the experiment, scientists divided male C57BL/6 mice into five groups. One group received a standard low-fat diet, while the others received a high-fat "Western" diet that provokes obesity. The food was supplemented with lyophilized powder from fruits and vegetables in different proportions: 0, 5, 10, or 15% of the diet by weight. The mixture included apples, bananas, berries, grapes, citrus fruits, spinach, carrots, broccoli, and tomatoes. The maximum dose, when converted for humans, corresponded to approximately 8-9 portions of fruits and vegetables daily.

After 20 weeks, researchers tested the animals' memory using a novel object recognition test - a standard method for evaluating learning and memory in rodents. The results were impressive: mice on the low-fat diet flawlessly distinguished new objects from familiar ones. In animals on the fatty diet without supplements, this ability was significantly reduced. However, in mice receiving the plant mixture, memory indicators improved proportionally to the increase in dosage. At the 15% supplement, the results were practically indistinguishable from the control group.

Notably, supplements at 5 and 10% did not prevent the development of obesity, whereas at a 15% supplement, weight gain was less than in mice without the plant powder. This fact indicates that memory preservation was not solely due to weight control.

To understand the protective mechanism, researchers measured the level of malondialdehyde in the liver - an important marker of oxidative stress. The high-fat diet significantly increased its content, while the fruit and vegetable supplement reduced the indicators, suggesting a decrease in systemic oxidative stress. According to the authors, this effect could protect neuronal pathways and cognitive functions.

In the future, scientists intend to study in more detail the effects of a plant-based diet on specific brain areas, including the hippocampus, and check whether the protective effect persists in humans during clinical trials.