Stress not only has negative effects on work and personal relationships, but it also increases the risk of many chronic conditions, such as heart disease and Alzheimer's disease, and is associated with higher death rates. However, following the Mediterranean Diet can help reduce the physiological effects of stress and promote healthy aging, according to a study conducted by researchers at the Wake Forest School of Medicine (North Carolina, USA).
The findings of the study , the first preclinical trial to measure the effects of long-term consumption of a Western versus Mediterranean diet on stress under controlled experimental conditions, were published last November in the journal Neurobiology of Stress .
"It is very difficult to control or reduce stressors in our lives, but we know that we can control our diet, and previous observational studies have suggested that a lower perception of stress is associated with a high consumption of fruits and vegetables," said Carol A Shively, a professor of Comparative Medicine and Pathology at Wake Forest School of Medicine and the study's principal investigator.
According to Shively, "Unfortunately, Americans eat a diet rich in animal protein and saturated fat, salt, and sugar, so we wanted to find out if that diet worsened the body's response to stress compared to the Mediterranean Diet, in which much of proteins and fats come from plant sources. "
Thus, the researchers studied the effects of chronic stress from low social status and the acute stress of being socially isolated for 30 minutes in 38 middle-aged animals that were fed a Mediterranean and Western Diet. The diets were formulated to faithfully reflect human diets, with proteins and fats derived primarily from animal sources in the Western group and primarily from plant sources in the Mediterranean group.
To determine the effect of diets on stress responses, the scientists measured changes in the sympathetic and parasympathetic nervous systems and in the adrenal gland hormone cortisol in response to acute and chronic stress.
The sympathetic nervous system participates in the "fight or flight" response and regulates bodily functions such as heart rate and blood pressure. The parasympathetic nervous system has opposite effects that help the body return to a calmer state. "The high activity of the sympathetic nervous system can be harmful to health, so maintaining a healthy balance between the two systems is important," said Shively.
Cortisol helps the body access the resources needed to fight or flee. However, if stress is continuous, cortisol levels remain high and damage tissues, according to the North American educational center.
Specifically, compared to animals fed a Western diet, those fed the Mediterranean Diet exhibited greater resistance to stress, "as indicated by the lower response of the sympathetic nervous system and cortisol to stress, and a more recovery. quickly after the stress is over ", the researcher pointed out.
"Our study showed that the Mediterranean Diet shifted the balance towards the parasympathetic nervous system, which is good for health, while the Western diet increased the sympathetic response to stress, which is like having the panic button on all the time, and that is not healthy ", has specified.
As the animals aged during the 31-month study, which is equivalent to about nine years in humans, the research group observed that the activity of the sympathetic nervous system increased. However, the Mediterranean Diet slowed down the aging of the sympathetic nervous system.
"The study findings suggest that population-wide adoption of the Mediterranean Diet can provide a relatively simple and cost-effective intervention to reduce the negative impact of psychological stress on health and delay the aging of the nervous system," Shively said.
Source: Mercacei