A 'GREEN' Mediterranean diet rich in plant matter, green tea, walnuts and very little meat or poultry may be even better for heart health than the traditional version, according to a new study.

Researchers in Israel found that participants on the revised 'green' version of the diet lost more weight from their waist over a six month period and experienced more significant improvements in their blood pressure and harmful low-density (LDL) cholesterol, which is associated narrowing of the arteries and heart attacks.

They also reported a "significant improvement in insulin sensitivity", which was more pronounced compared to volunteers on the traditional Med diet.

The findings are published today in the BMJ journal, Heart.

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Deaths from coronary heart disease (CHD) in Scotland have fallen by more than 32 per cent in the past decade, but mortality rates in Scotland remain higher than the UK as a whole and much higher than the EU average.

Around 5% of adults in Scotland are still living with a CHD diagnosis and there are more than 6000 deaths a year linked to heart disease.

The Israeli trial, led by researchers from Ben Gurion University, recruited 294 employees at the Nuclear Research Centre Negev who had an average age of 51 and evidence of excess abdominal fat or high cholesterol. The average BMI among volunteers was 31, making them moderately obese.

All participants were provided with a free gym membership and physical activity instructions.

One group received health dietary guidance (HDG) only, while the rest were divided into traditional and 'green' Mediterranean diets.

Both the Med diets involved restricted calorie intakes of 1500 to1800 calories a day for men, and 1200-1400 calories a day for women, and 28g of walnuts per day.

The Med diet was rich in vegetables,with poultry and fish replacing beef and lamb.

Those in the 'green' Med group were told to avoid red or processed meats, consumed for plants and foodstuffs rich in polyphenols - a type of antioxidant found in olives, raspberries, almonds, extra virgin olive oil, spinach and broccoli.

In addition, participants were asked to consume three to four cups of green tea per day and a plant-based Mankai protein shake at dinner, made using frozen cubes of duckweed - an aquatic plant - to replace animal protein.

After six months, the effect of each of the diets on weight loss and on cardiovascular and metabolic risk factors was assessed.

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Those on both types of Mediterranean diet lost more weight on average compared to the HDG group: 6.2kg (13.6Ibs) in the Green Med group and 5.4kg (12Ibs) in the traditional Med group, compared to 1.5kg (just over three Ibs) for those on a healthy diet.

Waist circumference shrank by an average of 8.6 cm (3.4 inches) among those on the Green Med diet, compared with 6.8 cm (2.7 inches) for those on the Mediterranean diet and 4.3 cm (1.7 inches) for HDG participants.

The green Med diet group achieved reductions of nearly 4% in LDL cholesterol, compared to 1% for the Med diet.

Overall, improvements in blood pressure, insulin resistance, and levels of C-reactive protein - a marker for inflammation - meant that the green Med diet delivered a two-fold reduction in participants' Framingham Risk Score, used to predict the likelihood of serious heart disease over the next decade.

The researchers caution that their sample included just 35 women, and they were unable to pinpoint the specific factors in the green Med diet responsible for the observed effects.

They conclude: “Our findings suggest that additional restriction of meat intake with a parallel increase in plant-based, protein-rich foods, may further benefit the cardio-metabolic state and reduce cardiovascular risk, beyond the known beneficial effects of the traditional Mediterranean diet.”