Some of the planet's healthiest people live off the coast of the Mediterranean. Their diet, appropriately packaged as the Mediterranean diet, is associated with astonishingly low risks of heart disease, diabetes, stroke, and metabolic syndrome.
The Mediterranean diet's stellar health effects have led some doctors to consider it the "ideal diet" for health and longevity, and rank it healthiest compared to other popular diets. In a new nutrition study, researchers discovered that a few small tweaks may make the Mediterranean diet even more effective — at least for men.
The researchers say the so-called "green Med" diet — which drastically limits red meat intake and increases green plant intake — can boost metabolism and cardiovascular health when paired with physical activity. These findings were recently published in the journal Heart.
Currently, the Mediterranean diet is the "most scientifically supported" dietary pattern for reducing cardiovascular risk, study co-author Gal Tsaban tells Inverse. Tsaban is a researcher at the Ben-Gurion University of the Negev.
"The results of the current study suggest that a green-MED diet may have even better metabolic effects, as compared to a diet following the healthy dietary guidelines and the traditional Mediterranean diet," Tsaban says.
HOW THIS AFFECTS LONGEVITY — Scores of studies suggest eating a plant-rich Mediterranean diet benefits the mind and body. Recent data also shows it can ramp up the metabolism and contribute to weight loss.
In this study, the team examined whether a greener version of the diet, meaning higher in green plant food sources and lower in red meat intake, could be even healthier.
The study included 294 people, but because only 35 of the participants were women, the final results were limited to men. The average age of the group was 51-years-old, and the participants were classified as sedentary and moderately obese. They were randomly assigned into three dietary groups:
- The first group received guidance on boosting physical activity and basic guidelines for achieving a healthy diet.
- The second received the same physical activity guidance plus advice on following a calorie-restricted (1500-1800 calories per day for men and 1200-1400 calories per day for women) traditional Mediterranean diet. This diet was low in simple carbohydrates, rich in vegetables, with poultry and fish replacing red meat. It included 28 grams per day of walnuts.
- The third group received physical activity guidance and were advised on how to follow a calorie-restricted green version of the Mediterranean diet. This included 28 grams per day of walnuts, three to four cups a day of green tea, limited red and processed meat, and higher quantities of plant foods. In an unusual twist, it also included 100 grams of frozen cubes of Wolffia globosa, a high protein form of the aquatic plant duckweed. This was taken as a green plant-based protein shake to partially substitute for animal protein.
All participants adhered to the diet assigned to their group for six months while reporting what they ate, drank, and their physical activity. After this experimental period, researchers tracked the effect of each of the diets on weight loss and cardiovascular and metabolic risk factors.
WHY IT'S A HACK — When examined head to head, the study team observed that the green Med group experienced the greatest reduction in waist circumference, LDL cholesterol (the sort considered to be 'bad' cholesterol), and systemic inflammation.
People who also ate both types of Mediterranean diet lost more weight than those in the basic healthy diet group. Green Med eaters lost 13.6 pounds (6.2 kilograms), Mediterranean eaters lost 12 pounds (5.4 kilograms), and the basic healthy diet lost 3.3 pounds (1.5 kilograms).
Waist circumference — a pivotal indicator of overall health — shrank by an average of 8.6 centimeters among those on the green Med diet, compared with 6.8 centimeters for those on the Mediterranean diet and 4.3 centimeters for those on the healthy diet.
The green Med diet group also achieved a reduction of nearly four percent of LDL cholesterol. Meanwhile, the Mediterranean diet group lost nearly one percent, and the healthy diet group didn't experience a significant loss.
Taken together, these changes resulted in improved heart health among those on the green Med diet —a nearly two-fold fall in the 10-year Framingham Risk Score. This is a calculation used to predict the likelihood of serious heart disease over the next decade.
Tsaban admits his team was "certainly surprised" by the results.
"We did not expect reductions in LDL cholesterol and an impressive —almost 25 percent — reduction in systemic inflammation," Tsaban says.
SCIENCE IN ACTION — Following the green Med diet doesn't require calorie counting or specific macronutrient combinations. Instead, one should eat an abundance of:
- Extra virgin olive oil
- Vegetables including leafy greens
- Whole Grains
- Fish and seafood
- A moderate amount of dairy and alcohol
- Limited red meat and processed meat
Based on these findings, the changes that transform the Mediterranean diet into a green Med diet — less meat, more green plants — may amplify beneficial cardiometabolic effects if followed by men. More research conducted on women is needed to know if they would see similar benefits.
HACK SCORE OUT OF 10 — 🥒🥗 🥑 (Extra green plants give the Mediterranean diet an edge, health-wise.)
Background A Mediterranean diet is favorable for cardiometabolic risk.
Objective To examine the residual effect of a green Mediterranean diet, further enriched with green plant-based foods and lower meat intake, on cardiometabolic risk.
Methods For the DIRECT-PLUS parallel, randomized clinical trial we assigned individuals with abdominal obesity/dyslipidaemia 1:1:1 into three diet groups: healthy dietary guidance (HDG), Mediterranean and green Mediterranean diet, all combined with physical activity. The Mediterranean diets were equally energy restricted and included 28 g/day walnuts. The green Mediterranean diet further included green tea (3–4 cups/ day) and a Wolffia globosa (Mankai strain; 100 g/day frozen cubes) plant-based protein shake, which partially substituted animal protein. We examined the effect of the 6-month dietary induction weight loss phase on cardiometabolic state.
Results Participants (n=294; age 51 years; body mass index 31.3 kg/m2; waist circumference 109.7 cm; 88% men; 10 year Framingham risk score 4.7%) had a 6-month retention rate of 98.3%. Both Mediterranean diets achieved similar weight loss ((green Mediterranean "6.2 kg; Mediterranean "5.4 kg) vs the HDG group "1.5 kg; p<0.001), but the green Mediterranean group had a greater reduction in waist circumference ("8.6 cm) than the Mediterranean ("6.8 cm; p=0.033) and HDG ("4.3 cm; p<0.001) groups. Stratification by gender showed that these differences were significant only among men. Within 6 months the green Mediterranean group achieved greater decrease in low-density lipoprotein cholesterol (LDL-C; green Mediterranean "6.1 mg/dL ("3.7%), "2.3 (-0.8%), HDG "0.2 mg/dL (+1.8%); p=0.012 between extreme groups), diastolic blood pressure (green Mediterranean "7.2 mm Hg, Mediterranean "5.2 mm Hg, HDG "3.4 mm Hg; p=0.005 between extreme groups), and homeostatic model assessment for insulin resistance (green Mediterranean "0.77, Mediterranean "0.46, HDG "0.27; p=0.020 between extreme groups). The LDL-C/high-density lipoprotein cholesterol (HDL-C) ratio decline was greater in the green Mediterranean group ("0.38) than in the Mediterranean ("0.21; p=0.021) and HDG ("0.14; p<0.001) groups. High-sensitivity C-reactive protein reduction was greater in the green Mediterranean group ("0.52 mg/L) than in the Mediterranean ("0.24 mg/L; p=0.023) and HDG ("0.15 mg/L; p=0.044) groups. The green Mediterranean group achieved a better improvement ("3.7% absolute risk reduction) in the 10-year Framingham Risk Score (Mediterranean"2.3%; p=0.073, HDG"1.4%; p<0.001).
Conclusions The green MED diet, supplemented with walnuts, green tea and Mankai and lower in meat/ poultry, may amplify the beneficial cardiometabolic effects of Mediterranean diet.