Association between dairy intake and multiple health outcomes: a scoping review of systematic reviews and...

Food-based dietary guidelines acknowledge non-fortified dairy foods as a source of multiple essential vitamins and minerals as well as high-quality protein. Considering the cultural significance of dairy foods in our diet and the increasing prevalence of non-communicable diseases, it is essential to continuously evaluate the entirety of data regarding the impact of dairy consumption on various health-related outcomes. A systematic literature search was performed in three databases: Medline, Embase, and Web of Science. Systematic reviews published between January 2014 and February 2024 based on randomized controlled trials (RCTs), prospective cohort studies, case-control studies, and/or cross-sectional studies in adults, focusing on the consumption of bovine dairy products were evaluated for inclusion. Reports from the World Cancer Research Fund on selected cancer outcomes were also included in this review. We identified 95 reports encompassing five dairy exposure categories on 29 different health outcomes. Out of 281 associations identified, 37.7% linked dairy consumption to a reduced risk, while 48.0% showed no association with disease risk. Inconclusive results were found in 10.0% of the associations, and 4.3% indicated an increased risk of adverse health outcomes. Overall, the evidence suggests that consuming dairy is not associated with an increased risk of non-communicable diseases or mortality. In fact, it may moderately reduce the risk of several health outcomes, including adverse cardiovascular outcomes and certain cancers such as bladder, breast, colorectal, liver, oral, and ovarian. Some studies have also linked dairy consumption to improved body composition, lower rates of type 2 diabetes, and better bone health.