Cheese Consumption and Human Microvascular Function

Increased dairy intake is associated with improved measures of blood vessel health. Dairy cheese, however, is often high in sodium. Dietary sodium can impair blood vessel function. The researchers examine if and how natural cheese may protect against impairments in blood vessel function caused by sodium. For this study, participants complete four 8-day controlled feeding periods in which they eat cheese (6 oz/day) or no cheese during a low-sodium or high-sodium base-diet. The participants complete baseline experiments while on their normal personal diet and then repeat experiments at the end of each controlled feeding period. In some of our experiments, the researchers use a technique called "microdialysis" (MD). With MD, the researchers perfuse some research drugs into the skin on the forearm through tiny tubing that mimics capillaries. These MD drugs mimic or block substances the body naturally makes to control the small blood vessels in the skin. The drugs remain in nickel-sized areas around the tubing and do not go into the rest of the body. The researchers also use a standard technique called "flow mediated dilation" (FMD) that uses blood pressure cuffs and ultrasound to look at the health of larger blood vessels in the body. FMD includes placing a small tablet of nitroglycerin under the tongue during part of the test.