Researchers found that each additional serving per week of skim or low-fat milk was associated with a 2% lower risk of hypertension, suggesting that skim or low-fat dairy may delay symptoms but will not prevent the risk as individuals get older.
The study also found that consumption of one extra serving of yogurt per week meant a 6% reduction in the risk of developing hypertension. Similar numbers were found for consumption of total dairy and other fermented milk products.
The study, titled Longitudinal Association of Dairy Consumption with the Changes in Blood Pressure and the Risk of Incident Hypertension: the Framingham Heart Study, was published in the British Journal of Nutrition.
Breadth of the study
Researchers examined the association between dairy consumption and changes in blood pressure, as well as the risk of hypertension, among more than 2,600 adults who participated in the Framingham Heart Study and did not have hypertension at the start of the study. Dietary intake and anti-hypertensive medication were measured through food questionnaires and self-reporting.
After a 14.6 year follow-up, just more than 1,000 people were diagnosed with incident hypertension. Those who consumed higher amounts of dairy products had a lower risk of being diagnosed with hypertension over the course of the study.
“Dairy consumption, as part of a nutritious and energy-balanced diet pattern, may benefit [blood pressure] control and prevent or delay the onset of [hypertension],” the study found.
Yogurt may be most helpful
While the study did find a positive interaction between skim or low-fat milk intake and hypertension and blood pressure reduction, researchers wrote that the inverse association weakened during later return visits. In fact, after eight years, the study said skim or low-fat dairy consumption was unrelated to hypertension.
Consumption of total dairy, total low-fat and fat-free dairy products, and fluid milk were inversely related to annualized blood pressure changes. A greater total intake of dairy foods and yogurt were associated with a lower incidence of hypertension, something that had “a constant hazards ratio over the average,” the study said.
Researchers said there is still more that needs to be looked at regarding use of dairy to reduce hypertension and blood pressure, but said dairy-rich foods likely have many vitamins and minerals that people in the US are lacking.
“Dairy foods are rich sources of various bioactive peptides, medium-chain fatty acids and micronutrients such as Ca, K and Mg, which are among the nutrients that are currently underconsumed by adult Americans,” the study said. “These nutrients may contribute to potential underlying mechanisms for the BP-lowering effect of dairy products.”
Yogurt, above other products, may work better for reducing blood pressure and hypertension, as it features about 50% more vitamins and minerals and 30% more protein per 227g serving than milk does.
While the study had a large sample size and 15-year follow-up window, “residual confounding factors cannot be completely ruled out,” the study said. Also, most of the study’s participants were Caucasians of European descent, meaning further studies will need to have a larger participant base to draw research from.
“Although it merits further confirmation, these observations support the potential benefit of dairy products on BP management and incidence of HTN,” the study concluded.
Source British Journal of Nutrition
doi: 10.1017/S0007114515003578
Longitudinal Association of Dairy Consumption with the Changes in Blood Pressure and the Risk of Incident Hypertension: the Framingham Heart Study
H. Wang, C. Fox, L. Troy, N. Mckeown , P. Jacques