Reading Time: 3 minutes
In a study published in the American Journal of Clinical Nutrition, researchers investigated the effect of adding dairy foods to a Mediterranean diet.
Thirty-one per cent of all deaths worldwide are caused by heart disease. Those who are at risk for cardiovascular disease are also at risk for a host of other health problems, including high blood pressure, higher (bad) cholesterol, obesity, and diabetes. Increasing exercise and dietary changes are some of the ways the risks for these health problems to be lowered.
Mediterranean diet does not always allow enough consumption of calcium
One of the healthiest dietary types is the Mediterranean diet. The Mediterranean diet includes a large amount of extra virgin olive oil, beans, vegetables, fruit, nuts and cereals; a medium amount of poultry, eggs, dairy foods, red wine, and fish; and a small amount of red meat and sweets. However, the Mediterranean diet does not always deliver the recommended daily allowance for all nutrients, especially dairy foods and calcium.
Researchers from the University of South Australia recently studied the health benefits of adding dairy foods as recommended by the Australian Dietary Guidelines. The results of the Australian study were published in the American Journal of Clinical Nutrition.
The study took place from April -June 2016 and followed 41 volunteers between 45 and 75 years old, who were at risk for heart disease. The group was randomly split into two groups. For the first eight weeks, Group 1 ate a typical Mediterranean diet that was supplemented with dairy foods to meet the Australian dietary guidelines (MedDairy). Group 2 ate a low-fat diet that had been designed as part of a previous study.
During the second set of eight weeks, both groups went back to their normal diets. Both groups switched to the alternate diet, either MedDairy or low-fat, for the final eight weeks of the study. The main measure of health was blood pressure, but researchers also measured BMI, body composition, and risk factors for diabetes. These assessments were taken at the clinic before the study began, at the end of the first and second eight weeks, and then again at the end of the study. Throughout the study, the participants measured and recorded their own blood pressure and heart rates at home in the morning, afternoon, and evening.
Mediterranean diet supplemented with dairy foods resulted in better health outcomes
The MedDairy diet resulted in much lower morning blood pressures, higher good cholesterol, and lower total cholesterol. The low-fat diet resulted in lower fat mass and higher lean mass.
There were a number of limitations to the study. The study compared the Mediterranean diet only to a low-fat diet, which could limit generalizing the study to the rest of the Australian population. Also, the MedDairy diet used in the study did not require as much extra virgin olive oil as is traditionally found in a Mediterranean diet, which could reduce heart benefits. The addition of dairy foods to the Mediterranean diet could reduce its potential benefits.
The way in which the study was conducted could have allowed bias in participants expectations. Researchers think that a larger, longer study would allow for better observations and would allow them to see any larger effects of the dietary changes.
The study has shown that simple changes to the diet, such as adding dairy foods, eating more fruits and vegetables, extra virgin olive oil, fish and eggs and eating less red meat and processed sweets can have a positive effect. The addition of three to four servings of dairy foods will improve calcium intake and lower the risk for heart disease.
Written by Rebecca K. Blankenship, B.Sc.
Reference: Wade A, Davis C, Dyer K, Hodgson J, Woodman R, Murphy K. A Mediterranean diet supplemented with dairy foods improves markers of cardiovascular risk: results from the MedDairy randomized controlled trial. Am J Clin Nutr. 2018;108(6):1166-1182. doi:10.1093/ajcn/nqy207