People who follow the ‘green Mediterranean’ diet burn a dangerous type of bodyfat at quadruple the rate of most dieters, a study has found.
Those who consumed the plant-based diet for 18 months saw their visceral fat levels shrink by 14 per cent, compared to just 4.5 per cent in a control group who ate a standard healthy diet.
Visceral fat wraps around vital organs and inside the abdomen typically giving someone a beer belly or apple body shape.
This type is the most dangerous because it is thought to release chemicals and hormones into the blood that trigger inflammation, linked to chronic diseases like heart disease and fatty liver disease. Its close proximity to the organs raises the risk.
The Mediterranean diet — high in fats and proteins but low in carbohydrates — has become extremely popular in recent years with a wealth of studies touting its benefits for longevity, reducing frailty and warding off cancer.
The above shows a healthy, Mediterranean and ‘green’ Mediterranean diet which was consumed in the study. The healthy diet (left) followed basic dietary guidelines, while the Mediterranean diet (center) tracked standard recommendations for this diet type containing plenty of beans, legumes, whole-grains, leafy greens, nuts and fish. The ‘green’ Mediterranean diet was a variation on this that saw consumers replace some meats with green tea and a duckweed shake
The ‘green’ Mediterranean diet still contains plenty of beans, legumes, whole-grains, leafy greens, olive oils, nuts and fish — but puts more emphasis on greens.
People in this group in the latest study were told to ditch red meat and poultry and consume three to four cups of green tea and a duckweed shake every day.
Researchers believe polyphenols — plant compounds that protect the body’s tissue against stress — help burn fat, which has been noted in previous studies.
Dr Hila Zelicha, an obesity expert at the University of Ben-Gurion in Israel, who was involved in the study, said: ‘A 14 per cent reduction in visceral fat is a dramatic achievement for making simple changes to your diet and lifestyle.’
Many experts consider visceral fat the true goal of weight loss, and a better indicator of someone’s health than the size of their waist.
Visceral fat builds up over time between organs, and produces hormones and poisons to heart disease, diabetes, dementia and premature death.
The above graph shows the percentage of visceral fat (Shown as VAT) lost among participants depending on the group they were assigned to
What was in the ‘green’ Mediterranean diet?
A large-scale study has suggested the ‘green’ Mediterranean diet can lead to a more rapid loss of visceral fat.
This is the most dangerous type of fat because it can wrap around organs and release chemicals that trigger inflammation.
Both diets suggest women should not consume more than 1,200 to 1,400 calories a day, while men should stick to between 1,600 to 1,800 calories.
They both had about 40 grams of carbohydrates a day for the first two months, which then rose to 80 grams a day afterwards.
Both groups were also told to consume less red, processed meats and poultry than in the standard Mediterranean diet.
The ‘green’ diet group was told to consume a 100 gram (g) duckweed shake and three to four cups of green tea once a day.
Both the standard Mediterranean diet group and the ‘green’ diet group were told to consume a handful of walnuts a day.
There is no hard and fast formula for what is in the Mediterranean diet.
But Harvard University said the diet plan tends to include the following:
- An abundance of plant foods like fruits, vegetables, whole grains, nuts, legumes
- Olive oil as the main source of fats;
- Cheese and yogurt, eaten daily in low to moderate amounts;
- Fish and poultry, eaten a few times a week in low to moderate amounts;
- Red meat, eaten infrequently in small amounts;
- Fresh fruit for dessert, eaten only a few times a week with sweets containing added sugars or honey;
- Wine, consumed in low or moderate amounts with some meals.
The study — published today in the journal BMC Medicine — looked at 294 adults who were 50 years old on average and had a BMI of 31, putting them in the obese category. Nearly nine in ten were men.
They were put onto three different diets — and asked to follow these from May 2017 to November 2018.
Two groups were told to follow a variation of the Mediterranean diet.
One followed a ‘green’, plant-based version, which included three to four green teas and one duckweed (Mankai) shake a day.
The other stuck to a standard Mediterranean diet.
Both had calorie restrictions of 1,400 calories a day for women, and 1,800 a day for men. They also ate less than 40 grams (g) of carbohydrate a day for the first two months, which was then raised to 80g.
In the third group, participants were advised to eat healthily but given no strict calorie counts. They were advised to loosely follow the Mediterranean diet.
During the study, each group was given 90-minute nutrition lessons every week for the first month and then once a month for the following five.
They were then given the lessons every other month until the end of the study.
All were asked to do aerobic and resistance training three to four times a week for 45 to 60 minutes. They were also given free gym memberships to encourage uptake.
MRIs were completed at the start and end of the trial to measure visceral fat.
Measurements were also taken of participants body-weight and waist circumference.
These measures dropped in both groups during the study, although there was no significant differences between the reductions.
In the ‘green’ diet group, participants lost 3.9 per cent of their body-weight and 5.7 per cent of their waist circumference on average.
Those on the standard Mediterranean diet lost 2.7 per cent and 4.7 per cent respectively.
And those on the healthy diet lost 0.4 per cent and 3.6 per cent.
It was the visceral fat difference that was noticeable, according to Dr Zelicha, who added: ‘Weight loss is an important goal only if it is accompanied by impressive results in reducing adipose tissue.’
Professor Iris Shai, a nutritionist who led the research, said: ‘We learned from the results of our experiment that the quality of food is no less important than the number of calories consumed.
‘The goal is to understand the mechanisms of various nutrients.’
The researchers suggest that the higher loss of visceral fat in the ‘green’ diet group was down to their diets having more polyphenols.
Levels of these plant-based compounds were higher in these participants compared to the other groups.
These take more energy to digest than in other groups, which scientists suggest led to more energy being burned off. This, in turn, led to a drop in weight.
The duckweed shake, consumed by those on the green diet, was high in protein, iron B12, vitamins as well as polyphenols.
People who follow the ‘green Mediterranean’ diet burn a dangerous type of bodyfat responsible for ‘beer bellies’ at a rapid rate (stock image)