The contributions of Peg Coleman to the raw milk movement

ARMM is excited to announce to our raw milk community that Peg Coleman, a microbiologist and risk assessor with an interest in the raw milk movement, has now started her own blog with interesting information that will appeal to a varied audience, not just scientists.

She consults and provides expert testimony on a variety of issues, with a focus on the natural microbiota of milks and benefits and risks to consumers.

Peg’s website is a new resource for learning about the risks and benefits of MICROBES, and to expand our understanding of microbes as our partners in health. She resides in rural New York, U.S.A. Peg provides scientific support to consumers, producers, regulators, decision makers, scientists and non-scientists who need to understand risks and benefits of microbes. She agrees with other scientists including Cornell University immunologist and author Rodney Dieter that frameworks for assessing, communicating, and managing risks AND benefits to human health and safety must no longer exclude the microbiota, our gatekeepers to health.

Peg has produced several scientific articles on her blog since August for her more intellectual scientific audience, but she has also produced some very practical posts and videos that may appeal to dairy farmers and raw milk supporters who are interested in raw milk science. According to her website

Peg Coleman began serving as a medical microbiologist and microbial risk assessor in the US federal government in 1992, and continued that work as founder in 2010 of the woman-owned small business Coleman Scientific Consulting (CSC).

Her assessments address the extensive gaps in scientific knowledge of microbial risks and benefits in health and disease.

CSC work on issues related to the microbiota of milks began with a presentation entitled Exploring Disagreements Regarding Health Risks of Raw and Pasteurized Human and Bovine Milk at the 2014 Society for Risk Analysis (SRA) annual meeting. Since then, she has invested time and energy into leadership in multiple projects. Peg says that scientists and the public can benefit by connecting with SRA, which is described as the world’s leading authority on risk science and its applications.

Peg takes an interest in how microbes provide benefits and risks in the environment and in human ecosystems.

In her lectures she talks about how the microbiota of healthy people can effectively inhibit colonisation and overgrowth by invading pathogens.

It was first observed in 1954 and later termed colonisation resistance. It is associated with a dense, diverse gut microbiota that does not trigger inflammation, but promotes homeostasis. It also involves specific interaction between the immune system and the microbiota.

How does a healthy microbiome protect us?

Colonisation resistance explains the power of beneficial microbes: they colonise the gut lining and prevent pathogens from doing the same or causing harm. In this article, Peg explains that a complex group of microbes form networks that cooperate with and enhance the activity of the epithelial cells lining the gut and the immune cells patrolling the gut. Some direct mechanisms are independent of host factors, including competition with pathogens for nutrients and access to host cells, as well as production of antimicrobial products. Some indirect mechanisms include stimulating host immune and epithelial cells to maintain barriers (physical, chemical, and cellular defences) against pathogens.

When the normally diverse protective microbiota is disturbed by antibiotics, drugs, or stresses in various environments, susceptibility to pathogens greatly increases.

Immunocompromised patients are at a higher risk than the average population due to abnormal or depleted microbiota, loss of colonisation resistance, and higher susceptibility to low pathogen loads or doses often present in hospital environments. Having a low diversity of species in the gut, low abundance of Lactobacillus (the microbes common in yogurt) and altered microbial-network structures are actually dangerous for humans.

Holistic approaches to Microbiota and Immunology

In this blogpost, Peg introduces Cornell professor Rodney Dietert, an immunotoxicologist in the College of Veterinary Medicine. In this video, Prof Dietert explains how beneficial bacteria provide colonisation resistance to protect against infections and pathogens, and why we need therapies to recolonise the microbiota after antibiotic use. Below is a summary of his slide listing multiple layers of ways in which using commensal, mutualistic microbes like Lactobacillus can block pathogens:

  • These microbes outcompete pathogens for the same nutrient source.

  • They can stimulate signalling that can block production of the pathogen’s nutrient source.

  • They stimulate mucin production to protect the mucus layer and inhibit pathogen access.

  • They directly produce bacteriocin (anti-microbial) effective against some pathogens.

  • They stimulate intestinal cells to make REG3-gamma (anti-microbial).

  • They produce short chain fatty acids to block pathogens and change host defense.

  • They metabolise primary bile acids to block pathogens.

  • There are signalling molecules that they can produce that can block quorum sensing capabilities in some pathogens


Prof Dietert says that there are multiple layers of ways in which mutualistic microbes in the gut, in the airways and on the skin or gastrointestinal tract (gut hereafter) naturally block pathogens from getting a foothold.

He says we need to be nurturing or managing our microbes as a first line of defence, and using it as a strategy, rather just making assumptions that health problems can be fixed by prescribing antibiotics alone.  

The Human Super-Organism

In one of her video blogposts, she introduces Rodney Dietert’s book The Human Super-Organism: How the Microbiome is Revolutionising Medical Thinking. He says that we are super organisms, complete without the bacteria become our partners in health. Our entire planet and its varied ecosystem are microbial in nature and even the upper atmosphere has a microbial layer.

In the video, Rodney made a prediction: in the near future, the highest priority of both preventative and therapeutic medicine will be managing microbes.

He encourages us all to promote our health by becoming microbial gardeners or shepherds watching over our microbial flocks.

Peg explains that the video engages a wide audience in discovering how our microbiota and immune systems can co-mature to avoid persistent inflammation and disease, as well as recover normal function after acute and chronic disease by first ‘minding our microbes’.

Whole Truth, Whole Milk Campaign

The SRA Whole Truth, Whole Milk Campaign launched through Upstate New York SRA this month as a joint project with other partners from Australia, New Zealand, the UK, and the US who are considering evidence of benefit and risk for the microbiota of milks. In this article, Peg explains that recent scientific evidence calls into question the basis for policies and laws that limit access to fresh unprocessed or raw breastmilk and milk from local dairies.

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“Evidence establishes reduced benefits to those who cannot choose the superfood, whole milk complete with its beneficial microbiota. Human milk banks around the world PASTEURISE donor breastmilk for fear of potential pathogens, and many states and countries around the world prohibit sale of raw cow milk based on fear of microbes. Multiple speakers pointed out that SRA is an ideal interdisciplinary organisation to convene diverse stakeholders for objective processes of deliberating evidence of benefits, as well as risks.”

The goal of the campaign is to provide objective documentation of evidence for benefits and risks of raw milks from humans and cows in the peer reviewed scientific literature and the popular press. Peg, Professor Dietert, and Dr. Warner North, Past-President of SRA, will collaborate as co-authors of the technical manuscript.

Please consider donating to SRA so Peg’s team can prepare a thorough, objective peer-reviewed manuscript on the benefits and risks of raw milks (from humans and cows), as well as educational materials targeting consumers, farmers, legislators, regulators, and scientists.

More information on the campaign will be available on Peg’s blog, the Upstate NY SRA website and also on this Go Get Funding page.

Science on the benefits of breast milk

Scientists report that breastfed infants ingest nearly a million bacteria a day!

Peg explains that breastmilk is alive with microbes essential for baby’s health and development, not just nutrients. Breastmilk microbiota are infant’s microbial partners in health. She posted a link to an article in Infection Control Today (ICT) about sugars in mother’s milk as a new class of antibacterial agents. It’s about the multiple benefits that human milk oligosaccharides or HMO's provide for infants. They are produced in the mammary glands as a component of milk. The mother’s genes encode HMOs, yet these are not digestible for infants. These oligosaccharides function as prebiotics, which are food for specific microbes, to encourage them to grow and colonise in the infant’s gut. The studies showed that milk from some donors directly kill a number of pathogens that can cause GI and respiratory infections in newborns and children.

These oligosaccharides, milk sugars or HMO’s both provide protection against certain pathogens, and feed beneficial microbes, encouraging them to colonise in the gut lining.

Support for the raw milk movement

churchtown dairy via peg.jpeg

Peg is also interested in the safe and effective development of the raw milk movement. She attended and provided information at a recent event, where an upstate New York biodynamic farm, Churchtown Dairy became the 17th to be listed with the Raw Milk Institute. Upstate New York has nearly 50 dairies licensed to sell raw milk from farm to consumer in 2018. The state has had a regulated raw milk industry for around 10 years.

The first blogpost regarding raw milk is around a video of stimulating conversations when Upstate NY Society for Risk Analysis (SRA) members, visited an organic dairy licensed to sell raw milk from its farm store. In the second blogpost video, there is a discussion (after the SRA members visited the dairies in the 1st post), where they sat down in the farm store to discuss benefits and risks of raw milk complete with its microbiota, clinically demonstrated to improve health and reduce risk of infectious and inflammatory or non-infectious diseases. SRA members admit that there is a lot they don’t know yet, and have to learn, but research on the microbiota disproves much of what we though we knew about microbes in milks and other foods based on 20th century science. Even though most had never visited a dairy or drank raw milk, they are open to new evidence that could assist people in balancing benefits and risks in their food choices.

A risk assessment lecture at the International Raw Milk Symposium 2015

On November 16, 2015, Peg, walked the audience through an exercise in risk assessment for consumers of raw milk and pasteurized milks. The Raw Milk Symposium was held in Anaheim, California, as part of the Weston A Price Foundation (WAPF) conference. Three other raw milk advocates also spoke: Sally Fallon Morell President of WAPF; raw dairy farmer Charlotte Smith of Champoeg Creamery; and raw milk farmer and director Mark McAfee of Organic Pastures and RAWMI. Watch the videos here.

A Bright Future for the Raw Milk Movement

Peg is pleased to inform us that she recently accepted the invitation from Mark McAfee, founder and Chairman of the Board of Director of RAWMI, to join the RAWMI Board! If you have not yet been to the RAWMI website, click here.

RAWMI is a non-profit international organisation dedicated to promoting and supporting the safe and hygienic production of raw milk and raw milk products for direct human consumption. RAWMI teaches well-established scientific principles and good manufacturing methods to assist farmers to produce hygienic safe raw milk. RAWMI assists farmers in developing and writing up risk assessment and management plans (RAMP) covering their whole farms.

Peg, Mark, and the other RAWMI Board of Directors members are looking forward to working together to inform the dairy industry, legislators, regulators, and especially consumers who are looking to make informed decisions about the safety and benefits of raw milk. RAWMI

encourages, promotes, and undertakes research, using approved scientific methods, to inform and enhance our education, outreach, and training programs.

Peg is sure that discussions of the benefits of the microbiota of milks will deepen the scientific basis of RAWMI trainings in the future.

Contact Peg at and follow her blog at, as well following her on Facebook and Twitter.

You can make the future of the raw milk movement even brighter by DONATING any amount to the SRA Whole Truth, Whole Milk Campaign here and sharing information about the campaign with your networks. If you are uncomfortable with online donations, feel free to mail a paper cheque to SRA (Society for Risk Analysis, c/o Tiffany Binnix, 950 Herndon Parkway, Suite 450, Herndon, VA 20170, USA), with Upstate NY SRA Campaign in the memo line.

View (and share) short videos about the campaign from three perspectives at the links below.

THANK YOU in advance for your support of this important work documenting scientific evidence of benefits and risks of raw milks from immunologic and ecological perspectives.

Posted on December 10, 2018 and filed under Health and Research, Raw Milk regulation, Immune compromised.