Will adding more dairy foods to a traditional Mediterranean diet help—or possibly hurt—your heart? Researchers at the University of South Australia set out to find the answer by assigning 41 middle-aged people at elevated risk for cardiovascular disease to one of two diets for eight weeks: a Mediterranean diet that included three or four daily dairy servings, about twice the usual amount (MedDairy), or a low-fat control diet, where participants lowered the fat content of their usual diet.
Dairy foods allowed in the MedDairy diet were low-fat milk, low-fat yogurt, a traditional yogurt dip (tzatziki), and cheese. Each group then switched to the other diet for another eight weeks.
Compared to when they were on the low-fat diet, the participants had improvements in morning blood pressure, afternoon heart rate, HDL (“good”) cholesterol, and triglycerides (fats in the blood) when on the MedDairy diet.
The improvements were small, and the study did not compare this dairy-enhanced Mediterranean diet to a traditional Mediterranean diet, but it at least showed that adding more dairy did not worsen heart disease risk factors and may have benefits. The study was published in the American Journal of Clinical Nutrition and did not have support from the dairy industry.
It has been proposed that anti-inflammatory effects of the Mediterranean diet, among other possible mechanisms, help reduce cardiovascular disease risk by lowering blood pressure, blood lipids, and oxidative stress and by improving blood sugar control (though no changes in the latter were seen in this study).
In addition to the dairy component, a traditional Mediterranean diet is high in vegetables, fruits, legumes, nuts, seeds, whole grains, and olive oil; moderate in fish, eggs, poultry, and red wine; and low in red meat and fried, processed, and sugary foods.
The Mediterranean diet provides about 700 to 800 milligrams of calcium a day, the researchers noted—which is not enough to meet the daily U.S. recommendation of 1,000 to 1,200 milligrams. If you are following a Mediterranean-type diet (a good idea), adding a couple more servings of dairy would help meet the daily calcium goal. Of course, it’s possible to get calcium from other sources than dairy, including leafy greens, almonds, canned salmon and sardines (with bones), and fortified foods—or with supplements, if necessary.
Also see Mediterranean vs. Vegetarian Diets.