Is this the healthiest diet in the world?

Southern Italy is home to Cilento, a rural, scenic area sometimes referred to as the “cradle” of the Mediterranean diet. Citizens of Cilento partake of a variety of fruits and vegetables grown on local farms, which form the foundation of their traditional cuisine.

The people of Cilento prepare their food with locally produced olive oil, as well as fish from coastal towns. They also drink local wine. For decades, experts have been amazed by the scores of centenarians who inhabit the region. They attribute these effects to both genetics and the Mediterranean diet.

So, it’s no wonder that the potential health benefits of the Mediterranean diet have been making headlines for years, both in the US and on an international level. As May is International Mediterranean Diet month, let’s take a closer look at what makes this diet so healthy.

What is the Mediterranean diet?

This diet consists of a high intake of monounsaturated fats, plant proteins, fish, and whole grains; moderate intake of alcohol; and minimal intake of red meats, refined grains, and sweets. Although it comes in different regional and cultural variations—with varying levels of pork, meat, and wine consumption—all Mediterranean diets are characterized by food that provide a high polyphenol content, a variety of fruits and vegetables, as well as healthy protein sources.

In total, 30% of calories in the diet come from carbohydrates consumed as whole grains and fruits. These foods are rich in fiber and polyphenols. Those following a Mediterranean diet eat at least 3-4 servings of fruits and 3-4 servings of vegetables daily.

In the Mediterranean diet, between 35% and 40% of total calories are derived from fats and oils, including olive oil, nuts, cheese, poultry, and fish. These foods are rich in omega-3 fatty acids and low in saturated fats.

The wine component of the Mediterranean diet may improve fasting blood glucose, reduce fasting insulin, and boost high-density lipoprotein cholesterol. These benefits could be augmented by the higher phenol content in red wine. Of note, these benefits were not found in people who drink white wine or water.

On a related note, moderate consumption of red wine could provide clinical benefit to obese individuals or those with metabolic syndrome. Moderate red wine consumption is defined as ≤ 1 glass per day for women and 1-2 glasses per day for men.

Both wine and olive oil, which are key components of the Mediterranean diet, are rich in polyphenols, which have antioxidant and anti-inflammatory activities. They also protect against heart disease, as well as offer anti-aging properties.

Clinical benefits of the Mediterranean diet

According to Bloomberg’s list of the Top 10 Healthiest Countries, Spain and Italy hold the #1 and #2 spots. This is due largely to the prevalence of the Mediterranean diet in both countries.

In observational studies, researchers have shown that adherence to the Mediterranean diet is tied to lower rates of obesity, diabetes, and heart disease. According to the results from a large randomized, controlled trial, participants experienced the most weight loss and reductions in low-density lipoprotein cholesterol, triglyceride, fasting serum glucose, and fasting insulin levels on the Mediterranean diet compared with low-carbohydrate or low-fat diets.

In other research, people on the Mediterranean diet experienced a 30% decrease in cardiovascular events and cardiovascular mortality during a period of 6 years vs those on a low-fat diet. Moreover, there was a 30% decrease in the frequency of diabetes among subjects on the Mediterranean diet.

In a meta-analysis involving six trials (n=2,650), researchers found, after 2 years of follow-up, that the Mediterranean diet was tied to favorable changes in body mass index, blood pressure, fasting plasma glucose, and C-reactive protein. They concluded that Mediterranean diets were superior to low-fat diets in decreasing cardiac risk factors and inflammation over the long run.

In addition to heart disease, the Mediterranean diet has been linked to lower rates of cancer. In a retrospective study from Italy, investigators examined the relationship between gastric cancer risk and adherence to the Mediterranean diet. This study involved 999 patients with gastric cancer and 2,628 controls who were admitted to the hospital for non-cancerous etiology. They found that subjects who followed the Mediterranean diet had a greater degree of lowered gastric cancer risk. 

To the inhabitants of Cilento, however, the Mediterranean diet is not something they choose to adhere to based on results from countless clinical trials and meta-analyses. They don’t need convincing of its benefits. To them, their diet is simply based on eating what the land and sea provide. Perhaps the number of centenarians that spring from there should be evidence enough.