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The green Mediterranean diet may help people maintain a moderate weight and protect against metabolic disease, including type 2 diabetes, by boosting an essential hormone. Davide Illini / Stocksy
  • New research suggests that higher levels of the hormone ghrelin, which is produced during periods of fasting or dieting, may help people lose fat and improve insulin sensitivity.
  • According to the study, participants who adhered to a green Mediterranean diet had ghrelin levels that were twice as high as people on other healthy eating plans.
  • The green Mediterranean focuses more on leafy greens and excludes all red meat.

New research has found that higher levels of the hormone ghrelin, which increases during periods of fasting and dieting, are associated with fat loss and improved insulin sensitivity.

Ghrelin is produced in the stomach and increases overnight when we sleep, fast, and then falls again after we eat a meal.

According to researchers, the findings — published in the Journal of Clinical Endocrinology & Metabolism — suggest that individuals who have higher ghrelin levels after experiencing weight loss have a lower risk of developing diabetes and other metabolic diseases.

The research team also found that people who followed the green Mediterranean diet, which is rich in leafy green vegetables and omits red meat, had significantly higher ghrelin levels than people who adhered to a more traditional Mediterranean diet.

All participants complemented their dieting with regular physical activity.

“Lifestyle-induced weight loss promoted consistent elevations in fasting ghrelin levels and, specifically, green-Mediterranean lifestyle was associated with greater elevation in fasting ghrelin and larger cardiometabolic benefits,” the first author of the paper, Dr. Gal Tsaban, a researcher and cardiologist at Ben-Gurion University of the Negev and Soroka University Medical Center in Beer-Sheva, Israel, told Healthline.

Ghrelin, nicknamed the “hunger hormone,” stimulates appetite.

It increases during periods of dieting and fasting, including when we sleep and drops soon after we eat a meal.

“During prolonged fasting conditions, this hormone seems to have an important role in maintenance of glycemic levels and metabolism,” Tsaban explained.

Lower ghrelin levels have been associated with obesity, insulin resistance, and the development of metabolic diseases.

Researchers aimed to explore further how fasting ghrelin levels fluctuate during various dieting interventions and how the hormone impacts obesity and metabolic processes, including insulin sensitivity.

During an 18-month period, the team evaluated fasting ghrelin levels in 294 individuals with either abdominal obesity or dyslipidemia — a health condition in which the blood has high levels of fat and cholesterol.

The participants were assigned one of three regimes — the Mediterranean diet, the green Mediterranean diet, or an eating plan following healthy dietary guidelines.

They all exercised regularly.

Those on the green Mediterranean diet had fasting ghrelin levels that were twice as high as those who followed a traditional Mediterranean diet or healthy eating plan.

The researchers suspect the elevated fasting ghrelin levels recorded in people who adhered to the green Mediterranean diet may explain why they had reduced liver fat and better cardiometabolic health.

“The results of our study suggest that adherence to the green-Mediterranean is feasible and that this lifestyle, as [any] healthy lifestyle, requires motivation and commitment from the individual who decides to make a change in his/her lifestyle,” Tsaban said.

The green Mediterranean diet includes more leafy greens than the traditional Mediterranean diet. It’s also free of red meat.

Study participants who followed the green Mediterranean diet also regularly drank green tea and ate mankai, a plant rich in fiber and polyphenols.

“Polyphenols are one of the nutrients needed to help promote optimal blood flow and cardiometabolic health, so having a concentrated form of it can help reduce inflammation and insulin resistance in the body,” said Michelle Routhenstein, a preventive cardiology dietitian and owner of Entirely Nourished, LLC.

Mankai is also a great source of protein, which helped compensate for the lack of protein from animal meat.

Because mankai is not readily available to many people, Routhenstein recommends looking for foods high in polyphenols — berries, purple grapes, white beans, extra virgin cold-pressed olive oil, basil, ginger, and vinegar.

“We must look at the whole picture of someone’s diet and lifestyle and focus on adding in therapeutic foods to thoroughly address metabolic and cardiac health,” Routhenstein said.

New research suggests that higher levels of the hormone ghrelin, which increases during periods of fasting and dieting, are associated with fat loss and improved insulin sensitivity.

The findings also suggest that individuals who have higher ghrelin levels after experiencing weight loss have a lower risk of diabetes and other metabolic diseases.

The benefits appear to be more pronounced when adhering to the green Mediterranean diet instead of other healthy eating plans, as the diet is rich in leafy greens and free of red meat.