Need for International Workshops to Deliberate Evidence of Benefits and Risks of Raw Milks

Abstract

Collaborative holistic approaches that incorporate recent evidence from multiple disciplines or sectors, including microbiology, immunology, and dairy and veterinary science, are crucial to enhancing sustainability, resilience, and health of humans and ecosystems around the world. Recent companion studies published in the Open Access journal Applied Microbiology [1-3] describe transdisciplinary analysis of benefits and risks for foodborne and environmental hazards using evidence map approaches for depicting the ‘state of the science’ and uncertainties related to both infectious and non-communicable diseases. The evidence documented in these studies [1-3] reflect the scientific advances of the recent decade summarized in the review by Oikonomou and colleagues [4] that describes the composition and functionality of mammalian milk microbiota and consortia naturally present in fresh unprocessed (raw) milks from healthy humans and ruminants. No longer is there consensus in the scientific community that mammalian milks are sterile, an outdated belief strongly based on germophobia of the 20th century. The current body of evidence [1-3] challenges 20th-century notions about microbes naturally present in milks of healthy mammals and merits further deliberation of the quality, veracity, and coherence of available evidence for assessing benefits and risks for regulatory decision making and other policy making. No benefit-risk analysis study was identified in our searches for pasteurizing donor breastmilk or cow milk. Further, much of the available evidence for benefits and risks of raw cow milk [3] is inconsistent with many outdated and unvalidated assumptions that formed the basis for simulations of potential risks to raw milk consumers in the past. One such simulation study by Food Standards Australia New Zealand (FSANZ) in 2009 [5] appeared to us to be driven by selected assumptions that seem to support preconceived pro-pasteurization biases articulated in the 2009 report, rather than to rely on sound scientific data. Many FSANZ assumptions (particularly: extrapolation of pathogen presence and levels in milk from cow feces; minimal effectiveness of temperature control, hygienic practices, Hazard Analysis and Critical Control Points (HACCP) programs, and test-and-hold programs; and high inherent risk) are falsified by the current body of evidence documented in this peerreviewed analysis [3]. From our perspective, recent data from clinical, mechanistic, and outbreak studies do not support the outdated assumptions that raw milk is inherently dangerous and that current hygienic management programs, including HACCP and test-and-hold programs, cannot ensure a safe, low-risk product for raw milk consumers.