“Green” version of Mediterranean diet improves efficacy

Article written by Bruce Sylvester

A green Mediterranean (‘green Med’) diet, using an increased amount of plant material and minimal red meat or poultry, appears to be better for cardiovascular and metabolic health than the regular Mediterranean diet, researchers reported on Nov. 23, 2020 in Heart.

“Education and encouragement to follow a green Med dietary pattern in conjunction with physical activity has the potential to be a major contributor to public health as it may improve balancing of cardiovascular risk factors, eventually preventing cardiovascular morbidity and mortality,” the authors said.

The investigators randomized 294 sedentary and moderately obese people (BMI of 31, average age 51) into three cohorts of 98 subjects each.

They provided to the first cohort with education about increasing physical activity and guidance for creating and enacting a healthy diet.

They gave to the second cohort guidance on physical activity plus instruction on enacting a calorie-restricted (1500-1800 kcal/day for men and 1200-1400 kcal/ day for women) standard Mediterranean diet low in carbohydrates, high in vegetables. They replaced red meat with poultry and fish. This diet included 28 g/day of walnuts.

They gave the third cohort physical activity guidance plus instruction on enacting  a “green” version of the Mediterranean diet (‘green Med’), which included 28 g/day walnuts, no red/processed meat and higher amounts quantities of plant matter. This diet included 3-4 cups/day of green tea and 100 grams of frozen cubes of Wolffia globosa (cultivated Mankai strain), a high protein form of duckweed, ingested as a green protein shake.

At six months, the investigators evaluated all subjects for weight loss and changes in cardiovascular and metabolic risk factors.

Subjects on the green Med diet lost an average of 6.2 kg compared to 5.4 kg on the Mediterranean diet and 1.5 kg on the healthy diet.

Subjects on the green Med diet achieved waist circumference shrinkage of an average of 8.6 cm compared to 6.8 cm for the Mediterranean diet and 4.3 cm for the healthy diet.

Green Med subjects achieved greater reductions in in low-density (LDL) cholesterol of 6.1 mg/dl, or approximately 4%, compared to 2.3 mg/dl (nearly 1%) for the Mediterranean cohort and 0.2 mg/dl for the healthy diet group.

Cardiovascular and metabolic risk factors were relatively more improved among green Med diet subjects, including reductions in diastolic blood pressure, insulin resistance and an C-reactive protein. The ‘good’ to ‘bad’ cholesterol ratio also increased.

Combined, the changes among the green Med diet subjects resulted in a significant reduction the 10-year Framingham Risk Score, which is used to predict onset of serious heart disease.

The researchers noted that the study population included only 35 women.

The authors concluded “This study’s results suggest that while calorie restricted MED diets promote weight loss and benefit metabolic state, the green MED diet, lower in meat/poultry and richer in green plants food sources, provides a greater WC [waist circumference] regression and significant improvement in cardiovascular risk, with a decrease of ~4% in LDL-C [LDL cholesterol] and ~20% in hsCRP [highly sensitive quantification of CRP] within 6 months.”