Food is a powerful health promoter. The essential nature of vitamins and minerals from food is well understood. Research has established the role of numerous phytonutrients, such as sulphoraphane, in reducing risk of chronic disease. And now an intriguing article in Circulation 2017 is highlighting how food affects function.
High density lipoproteins (HDL) circulate through our bloodstream eliminating the bad plaque promoting LDL cholesterol. So of course we want to raise HDL levels. This is done through exercise, stopping smoking, avoiding trans fatty acids and consuming healthy monounsaturated fats. But I have had many patients do all this and get discouraged when their HDL level did not bump up. So now we learn it is not all about the numbers.
Researchers working on a large study of the Mediterranean diet randomly selected about 300 subjects who were at high risk of cardiovascular disease. Everyone was on a nutrient-rich Mediterranean style diet but one-third of them added four tablespoons a day of virgin olive oil, one-third added a handful of nuts and the last third followed just the prescribed diet.
After one year, interesting results emerged. None of the diets increased HDL levels significantly but they did improve HDL function. This functional improvement included removing cholesterol from plaques and transporting it to the liver for elimination, the ability to relax blood vessels and preventing the oxidation of LDL, which increases plaque. All the diets produced these functional changes but the diet enriched with the virgin olive oil had a larger functional improvement. This is confirmation that dietary changes are benefitting cardiovascular health even if you do not see HDL changes on a routine blood test. Trust the food — it is the basis of health.
The Mediterranean diet for the research emphasized vegetables, fruit, legumes such as beans and chickpeas, whole grains and moderate amounts of fish and poultry. Intake of red meat, sweets, highly processed foods, high sugar foods was reduced. For more science and recipes about the Mediterranean diet go to http://oldwayspt.org/
Sheah Rarback is a registered dietitian on the faculty of the University of Miami Leonard M. Miller School of Medicine. Follow her on Twitter @sheahrarback.