We know what you're all thinking, another article on the Mediterranean diet and its many benefits. We've heard them all! But have you?
A new study by the researchers at Wake Forest School of Medicine, part of Wake Forest Baptist Health, has discovered something possibly groundbreaking.
The findings have led researchers to believe that eating a Mediterranean diet may provide a relatively easy way to help lessen the physiological effects of stress and promote healthy ageing.
These findings, the first preclinical trial to measure the effects of long-term consumption of a Western versus Mediterranean diet on stress under controlled experimental conditions, are published in the current online edition of the journal Neurobiology of Stress.
"It is very difficult to control or reduce stressors in our lives," said Carol A. Shively, PhD, professor of pathology and comparative medicine at Wake Forest School of Medicine and principal investigator of this study.
"But we do know that we can control our diet, and previous observational studies have suggested that lower perceived stress is associated with high fruit and vegetable consumption.
"Unfortunately, Americans consume 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 a Mediterranean diet, in which much of the protein and fat come from plant sources."
The researchers studied the effects of the chronic stress of low social status and the acute stress of being socially isolated for 30 minutes on 38 middle-aged animals that were fed either a Mediterranean or Western diet.
The diets were formulated to jointly reflect human diets, with protein and fat derived mainly from animal sources in the Western group and primarily from plant sources in the Mediterranean group.
To determine the diets' effect 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 is connected to the 'fight or flight' response felt during periods of acute stress and controls bodily functions such as heart rate and blood pressure. The parasympathetic nervous system has opposite effects that help the body return to a calmer, zen-like state.
High sympathetic nervous system activity can be harmful to health, so maintaining a healthy balance between the two systems is important, Professor Shively stated.
Cortisol, the body's main stress hormone, helps the body access the resources needed to fight or flee. However, if stress is continuous, cortisol levels stay high and damage tissues in our bodies. This stress is referred to as 'Chronic Stress'.
In comparison to the animals fed a Western diet, those fed the Mediterranean diet exhibited enhanced stress resilience. This was indicated by lower sympathetic nervous system and cortisol responses to stress, and more rapid recovery after the stress ended, Professor Shively said.
"Our study showed that the Mediterranean diet shifted the balance toward the parasympathetic nervous system, which is good for health," Shively mentioned.
"By contrast, the Western diet increased the sympathetic response to stress, which is similar to having the panic button on all the time, and that isn't healthy."
As the animals aged over the 31-month study, which is equivalent to about nine years in humans, the research group noted that sympathetic nervous system activity increased!
Nevertheless, the Mediterranean diet slowed the ageing of the sympathetic nervous system.
The study's findings suggest that population-wide adoption of the Mediterranean or Mediterranean-style diet may provide a relatively simple and cost-effective intervention to reduce the negative impact of psychological stress on health and delay nervous system ageing, Shively said.
Hence, it can be safely declared that Greek people, in especially ancient Greeks, have the healthiest diet in the world. And that if we truly follow it as our ancestors did, we will reap great benefits, both physically, psychologically and mentally.
A simple rundown of what the Mediterranean entails:
The Mediterranean diet is simply an ancient way of eating whole, fresh foods that are in season. It is based around lots of vegetables, nuts, seeds and grains, and limited consumption of meat from animals. It is not as strict as other 'fad diets', allowing a wide variety of foods that can be enjoyed, this makes it easier to follow. The diet promotes the eating of foods that are high in Omega-3s and healthy fats, such as;
- Olive oil
- Wholegrain, wholemeal bread
- Seasonal fruits
- White Cheeses (Feta, Haloumi)
To read more about the Mediterranean diet and its myriad of health advantages, click here.
To read more about Professor Carol A. Shively and her incredible ongoing research on the effects of the Mediterranean Diet, click here.
The aforementioned study was supported by the National Institutes of Health R01HL087103, RF1AG058829, R01HL122393, U24DK097748, and the Wake Forest Claude D. Pepper Older American Independence Center P30AG012332.