Mediterranean Diet Tied to Lower Blood Pressure, Greek Study Shows

Looking at data spanning 20 years, Greek researchers found that people who consistently followed a Mediterranean-style diet had a lower risk of developing hypertension (high blood pressure) than those with the lowest adherence to the diet.

According to the Centers for Disease Control and Prevention (CDC), hypertension affects nearly half of all adults in the United States.

It occurs when someone’s blood pressure is 130/80 millimeters of mercury (mm Hg) or higher. When left untreated, hypertension can lead to heart disease, stroke, and even kidney disease.

Researchers from the School of Health Sciences and Education at Harokopio University of Athens, in Greece, conducted a study that lasted 20 years to see what benefits adhering to the Mediterranean diet can have.

The study, published in the European Journal of Clinical Nutrition, began in 2002 and lasted through 2022. The researchers invited 4,056 people living in Greece to participate, and of that group, 3,042 signed up.

The average age of the participants at the beginning of the study was 41 years, with men making up 44 percent of the group and women making up 56 percent. One of the requirements for participating was that participants could not be hypertensive at the beginning of the study.

The researchers collected a variety of information on the participants at the beginning of the study. They made sure the participants did not have cardiovascular disease, checked glucose and cholesterol levels, checked their body weight and blood pressure, and conducted an interview to gauge their dietary and lifestyle habits.

Participants in the study followed the Mediterranean diet

To see how well the participants followed aspects of the Mediterranean diet at the beginning of the study, they assigned them a MedDietScore, scoring positively based on consuming the following food groups:

• fruits
• vegetables
• whole grains
• potatoes
• legumes
• fish
• olive oil

The participants received points based on these food groups. Higher scores indicated better adherence to the diet. Participants could lose points for consuming “non-Mediterranean” foods or food groups, including full-fat dairy products, poultry, and red meat.

Over the next 20 years, the researchers followed up with the participants to assess their MedDietScore, check their vitals, and look for the development of hypertension, high cholesterol, diabetes, and cardiovascular disease.

Results of the study

The researchers included 1,415 participants in their final sample. They found that participants who closely followed the Mediterranean diet had the lowest risk of developing hypertension.

Participants in the group who had the lowest MedDietScore – and therefore did more poorly at adhering to the diet – had hypertension rates of 35.5 percent at the end of the study. The middle group had a hypertension rate of 22.5 percent.

In comparison, the group with the highest MedDietScore, who adhered to the Mediterranean diet the best, had a hypertension incidence rate was 8.7 percent.

The scientists also analyzed what differences adhering to the Mediterranean diet had over time. Diet adherence in the study was measured using a longitudinal change in the MedDietScore from the initial assessment in 2002 to a follow-up in 2012.

The researchers were interested in seeing what difference sticking close to the diet consistently, rather than inconsistent adherence, might have.

According to the study paper, “[c]ompared to subjects who were consistently away from the Mediterranean diet, only those who were consistently close exhibited a 46.5% lower 20-year [hypertension] risk.”

Overall, the study results emphasize the importance of eating habits in reducing the risk of developing hypertension. It also shows that the Mediterranean diet can be instrumental in lowering hypertension risk.