This is part of the public record and is presented for information purposes.
Testimony of John F. Sheehan, B.Sc. (Dy.), J.D., Director, Division of Plant and Dairy Food Safety
Office of Food Safety, Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration
before the Health and Government Operations Committee, Maryland House of Delegates, March 17, 2009
RAW MILK IS INHERENTLY DANGEROUS
Raw milk is inherently dangerous and may contain a whole host of pathogens including Enterotoxigenic Staphylococcus aureus, Campylobacter jejuni (C. jejuni), Salmonella species, Escherichia coli (E. coli 0157H:7, Enterohemorrhagic E .coli - EHEC, Enterotoxigenic E. coli - ETEC), Listeria monocytogenes, Mycobacterium tuberculosis, Mycobacterium bovis (M. bovis), Brucella species (B. abortus being mainly associated with cattle and B. melitensis being mainly associated with goats ), Coxiella burnetii and Yersinia enterocolitica to name but a few. Incidence rates for the presence of these pathogens in raw milk reported in the literature are variable. As one might expect, there are variations in incidence rates between countries and even within regions of countries. There are also variations in incidence rates reported for the three main commercial milks (bovine [cow], ovine [sheep] and caprine [goat]). Van Kessel et al. (1) reported in 2004 on the prevalence of Salmonellae and Listeria monocytogenes in bulk tanks on U.S. dairies. They reported a 2.6% incidence rate for Salmonellae and a 6.5% incidence rate for Listeria monocytogenes.
They commented that “although the prevalence of these organisms was low, inappropriate handling of raw milk could result in bacterial growth and substantially increase the potential risk to consumers of raw milk and raw milk products.” These incidence rates were reported even with very low standard plate counts (total bacterial counts) at <5000 cfu’s /ml (less than 5000 colony forming units per milliliter) being reported for the vast majority of samples analyzed for the pathogens. This is important to note because it is clear illustration of the fact that a simple standard plate count (or “bacteria count”) is not an indication of the safety of milk. A low standard plate count clearly does not mean that milk will be pathogen-free. Furthermore, even though Van Kessel et al characterized the incidence rate as "low," the mere possibility of Salmonella contamination often leads to food recalls even where Salmonella may not be present in all of the food recalled. For example, hundreds of firms recently have recalled products made with certain peanuts and peanut products because of the possibility that they may be contaminated with Salmonella.
Many of the above-mentioned microorganisms can cause very serious, sometimes life altering and sometimes even fatal disease conditions in humans. With pregnant women, Listeria monocytogenes-caused illness can result in miscarriage, fetal death, or illness or death of a newborn infant. Enterohemorrhagic E.coli (EHEC) infection has been linked to hemolytic uremic syndrome (HUS), a condition that can cause kidney failure and death. If infected with EHEC, young children are particularly susceptible to contracting HUS as unfortunately has recently happened in this country.
Raw milk should not be consumed by anyone, at any time, for any reason. FDA’s opinion in this matter is entirely consistent with that of the American Medical Association, which holds as policy the position that “all milk sold for human consumption should be required to be pasteurized” (H-150.980, Milk and Human Health). The aged, infirm, young and immuno-compromised are most at risk for severe infections from pathogens that may be present in raw milk. Yet, oftentimes, we hear arguments made by raw milk advocates that these are the very people who should consume raw milk because of its alleged curative or medicinal properties.
Claims that raw milk has miraculous disease-curing properties are not supported by the scientific literature. The scientific literature is, however, rife with reports of foodborne illness attributed to the consumption of raw milk, including an article by Werner et al. (2) which reported on the incidence of Salmonella Dublin infections in California between 1971-1975. During that time, the mean annual incidence of Salmonella Dublin infections in California increased five-fold. Investigations of the cases showed an association with raw milk consumption and that all of the implicated raw milk came from just one dairy. Eighty-nine of the 113 victims were hospitalized and 22 of them died. Almost half of the patients had serious underlying, non-infectious diseases such as leukemias and lymphomas. As we know, the immune system with such persons is often compromised as a result of the treatments they are receiving.
In 1997, Keene et al. (3) reported on a prolonged outbreak of E.coli O157:H7 which was caused by the consumption of raw milk sold at Oregon grocery stores. Outbreaks began in 1992 and continued until June of 1994. When the dairy that was the source of the raw milk was identified, it was discovered that 4 of the 132 animals in the herd were initially positive for
E.coli O157:H7. Despite public warnings, new labeling requirements and increased monitoring of the culprit dairy, illnesses continued until June 1994, when retail sales were finally stopped. The authors concluded that without restrictions on distribution, E.coli O157:H7 outbreaks caused by raw milk consumption can continue indefinitely, with infections occurring intermittently and unpredictably.
Proctor and Davis (4) reported on E.coli O157:H7 infections in Wisconsin between
1992-1999. During that timeframe, there were 1333 cases, even though the disease only became reportable in Wisconsin in April 2000. The highest age-specific mean annual incidence, at 13.2 cases per 100,000 population, occurred in children aged 3-5 years old. Among case patient identifiable exposures, consumption of raw milk/milk products was among the top three causes most frequently noted. Kernland et al. (5) reported on the causes of HUS in childhood in Switzerland. Among the causes was the consumption of raw milk, which resulted in the authors concluding that pasteurization of raw milk is likely to have a positive influence on the incidence of HUS. Allerberger et al. (6) reported on a specific incident in Austria in which two children contracted E.coli O157:H7 infection and subsequently developed HUS after consuming raw milk. The authors concluded that “it is prudent to remind them (parents and teachers) that children should not be given unpasteurized milk.”
When one reads all the literature available on the association between E.coli O157:H7, HUS and raw milk, one wonders whether children themselves would choose to drink raw milk if they knew that raw milk might make them very ill, cause them to lose their kidneys, or even kill them. Given a child’s enthusiasm for life, I doubt very much that they would. Since children cannot and do not know about such matters, however, it is incumbent upon those of us who do know and are responsible for protecting them to ensure that the likelihood of their contracting foodborne disease from any food, including the milk that they drink, is an ever-diminishing prospect. Our collective actions should tend to make the food supply safer overall and not result in a lessening of the level of protection which we afford ourselves as a society. Permitting raw milk sales, or the operation of so-called “cow-share” schemes to occur within any given jurisdiction, will not result in the maintenance or further strengthening of our food safety systems. On the contrary, permitting such sales and schemes will inevitably result in an increased incidence of foodborne illness.
Indeed, a farm operating a cow-sharing scheme in the state of Washington and which was engaged in the unlawful interstate distribution of raw milk, was relatively recently determined to have produced milk which was adulterated with E.coli O157:H7 and to have caused an outbreak of foodborne illness. There were eighteen victims identified in that outbreak, which represented 13% of those who reported consuming raw milk originating from the culprit farm. Unfortunately, the median age of the victims was just 9 years. Five of these victims, aged between 1-13 years, were hospitalized and four of these unfortunate children had HUS. Seventeen of the victims were farm “shareholders” or the children of “shareholders” and one other victim, a child of ten years of age, was a friend of a “shareholder.” The Centers for Disease Control and Prevention (CDC) issued, on March 2, 2007, a report on this outbreak in its Morbidity and Mortality Weekly Report (MMWR). That MMWR report may be found at http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5608a3.htm.
On the day of the publication of this MMWR, March 2, 2007, the state of Pennsylvania issued a press release announcing that a Pennsylvania farm engaged in the practice of selling raw milk had been determined to be responsible for an outbreak of Salmonellosis in that State. The CDC has since issued an MMWR describing the Pennsylvania outbreak in 2007. It may be found at @@http://www.cdc.gov/mmwR/preview/mmwrhtml/mm5644a3.htm@2.
An outbreak of foodborne illness involving E.coli O157:H7 also occurred in California in 2006. This outbreak was determined by California to likely be caused by a dairy owned by a raw milk advocate. The evidence linking these illnesses to this dairy was strong enough to prompt California authorities to order the milk to be recalled. According to California authorities, all of the victims in this outbreak were children. FDA had previously issued a warning letter to this same dairy farm on February, 24, 2005, for the unlawful distribution of unpasteurized milk, buttermilk, butter, cream and colostrum in interstate commerce, in finished form for human consumption, an action which is in violation of the Public Health Service Act, Title 42, U.S. Code, Sections 264 (a) and 271 (a) and Title 21, Code of Federal Regulations, Section 1240.61 (a). A copy of this warning letter is available at http://www.fda.gov/foi/warning_letters/archive/g5215d.pdf .
E.coli O157:H7 is not the only pathogen of concern for the very young. Schmid et al (7) reported on Campylobacter jejuni infections in Dubuque, Iowa over a twelve-month period. Forty-six of 53 victims participated in the case control study performed. Twenty-one of the 46 cases occurred in children less than ten years of age. The age-specific attack-rate was highest for children aged one to four years. Fifteen of the 46 had consumed raw milk in the week before the onset of their illness. Twelve of the 15 who had consumed raw milk were less than 10 years old. The authors concluded “eliminating the consumption of raw milk will depend on educational efforts.”
FDA agrees that continued educational efforts are needed to impart an understanding of the dangers of raw milk to all, but educational efforts alone will not suffice. In order to protect the public health, raw milk should not be permitted to be sold for human consumption, nor should people be allowed to attempt to skirt laws banning direct raw milk sales by operating so-called “cow share” schemes. The CDC agrees with FDA in this regard. In the March 2, 2007, MMWR discussed above, CDC stated that “State milk regulations and methods for their enforcement should be reviewed and strengthened to minimize the hazards of raw milk” (emphasis added). House Bills 1080 and 1015 which are now before this body for consideration would operate to weaken Maryland laws governing public health protection by allowing sales of raw milk to occur. With respect to House Bill 1080, which would allow for “cow shares”, we note that the Circuit Court for Frederick County, Maryland recently decided that “cow share” schemes (or “Bovine Sale and Agistment Agreements” as the subject contract was termed by the raw milk vendor who was the subject of the case) were nothing more than contracts for the sale of raw milk, since, in exchange for the monetary consideration being tendered to the vendor, the customer was receiving milk. The court found: “the Agreement does involve the transfer of the production of the cows as the return for investment in the herd. That production is raw milk. As such, despite language to the contrary, the Agreement involves the transfer of raw milk for consideration. That is a sale.” (Oyarzo v. Maryland Department of Health and Mental Hygiene, appeal pending)
Allowing any type of raw milk sales directly to consumers does increase the probability of serious harm occurring to Maryland consumers, especially children, the aged, infirm and immunocompromised. House Bills 1015 and 1080 would significantly distance Maryland’s regulation of raw milk from the advice being given by the CDC, FDA, and many notable others. In a press release issued jointly by both CDC and FDA on March 1, 2007, the agencies noted that in addition to CDC and the FDA, “the American Medical Association, the American Academy of Pediatrics, the National Conference on Interstate Milk Shipments, the National Association of State Departments of Agriculture, the Association of Food and Drug Officials and other organizations have endorsed the pasteurization of milk and prohibition of the sale of raw milk and products containing raw milk”.
It is not only the very young, the aged, infirm and immunocompromised that can fall victim to the pathogens which may be present in raw milk. Anyone can be a victim, including healthy young adults, as was reported by Blaser and Williams (8) when they described how 19 of 31 college students developed an acute gastrointestinal illness caused by C. jejuni infection after a visit to an Oregon farm. It was determined that 3 others had an asymptomatic infection. Twenty-two of 25 students who had consumed raw milk for the first time became infected.
Raw milk advocates have claimed “It is not even clear that tuberculosis (TB) can be contracted from milk products” (Weston A. Price Foundation PowerPoint presentation available on-line entitled “Raw Milk and Raw Milk Products”). These advocates are wrong. It is clear to the medical community, to scientists, food technologists and those otherwise familiar with milk and milk products and the history of pasteurization that TB can be contracted from raw milk and raw milk products. Prior to the advent of pasteurization, M. bovis was reported to cause between 6-30% of all TB cases in the United States. (Karlsen and Carr) (9). De la Rua-Domenech has also recently produced a very useful review on human M. bovis infections (10) which might be of further interest to this Committee.
STATISTICS ON DISEASE OUTBREAKS ASSOCIATED WITH RAW MILK OR RAW MILK PRODUCTS
CDC’s MMWR for the week of March 2, 2007, which I discussed above, reported that from 1998 to May 2005, 45 outbreaks of foodborne illness implicated unpasteurized milk, or cheese made from unpasteurized milk. Those outbreaks accounted for 1,007 illnesses, 104 hospitalizations, and two deaths. The CDC also noted that between 1973-1992, 87% of the raw milk outbreaks occurred in those states which allowed for raw milk sales to consumers while consumption of raw milk was estimated to have been less than 1% of the total milk sold in those states.
Raw milk advocates have claimed that “between 1984 and 2002, reports of outbreaks associated with raw milk produced in the U.S. are almost non-existent”. (Weston A. Price Foundation PowerPoint presentation available on-line entitled “Raw Milk and Raw Milk Products”) This is not the case. FDA’s review of outbreaks for this period indicates that there were 35 outbreaks attributed to raw milk, an average of two outbreaks per year.
When considering these statistics, it is important to consider that not all outbreaks are actually recognized and that, even when they are recognized, not all of them are reported to CDC. Additionally, it is impossible to capture all of the incidents of individual illness that occur. Generally, outbreaks indicate a much greater incidence of unreported sporadic illness from a food, such as raw milk.
Pasteurization is required for all milk and milk products in final package form intended for direct human consumption which move in interstate commerce. (21 CFR 1240.61) The only exceptions to this requirement are for certain cheeses and those exceptions are not absolute but come with certain other requirements relative to the manner by which any raw milk cheese must be ripened. In promulgating this regulation, FDA made a number of findings relative to raw milk, including the following: "Raw milk, no matter how carefully produced, may be unsafe" (52 FR 29514, Aug. 10, 1987).
The case that prompted FDA to promulgate 21 CFR 1240.61 was Public Citizen v. Heckler, 653 F. Supp. 1229 (D.D.C. 1986). In its holding, the federal district court concluded that the record presented "overwhelming evidence of the risks associated with the consumption of raw milk, both certified and non-certified." Id. at 1238. The court stated that the evidence FDA has accumulated concerning raw milk has “conclusively shown…. raw milk is unsafe" and that "[t]here is no longer any question of fact as to whether raw milk is unsafe". Id. at 1241.
Pasteurization will destroy all of the pathogens that I have mentioned thus far and others that I have not mentioned. For example, pasteurization is also destructive of Mycobacterium paratuberculosis, the causative organism of Johne’s disease in cattle. Clearly, pasteurized milk rationally can never be considered more hazardous than raw milk, contrary to the claims of raw milk advocates. In fact, it is universally agreed within the scientific community that pasteurization has made milk a much safer food for human nutrition.
Raw milk advocates have mentioned that Bacillus cereus and Clostridium botulinum spores may survive pasteurization, labeling these microbes as “heat-resistant pathogens.” Microbial endospores are indeed very resistant to heat and chemical treatments, but the vegetative cells of these microbes are not heat resistant and will be destroyed by pasteurization.
B. cereus spores are quite common in milk, raw or otherwise and are thus a common cause of spoilage concerns within the dairy industry. However, the presence of C. botulinum spores in milk is not a very common occurrence. Before either of these microbes can pose food safety concerns with milk or milk products, very high population levels must be reached, a condition that does not ordinarily occur in the collection and processing of milk and milk products. Interestingly, in alleging that consumers are avoiding commercial milk because it is pasteurized (which is not true insofar as FDA is aware), raw milk advocates also claim that consumers do not like the fact that cows are allegedly kept in confinement, and fed rations designed to enhance milk production, a situation which they claim causes poor health and disease. In support of such a notion, raw milk advocates claim that Dutch researchers found much lower rates of Salmonella infections in dairy herds and cows with access to pasture, but they neglect to mention, or are perhaps unaware, of other Dutch research (Slaghuis et al.) (11) that indicates that cows fed on pasture during the summer had higher levels of B. cereus spores in their milk than cows which were housed during the summer. Thus, it appears that raw milk advocates are somewhat selective about the research which they choose to discuss when it comes to the subject of cattle feeding and its impact upon milk microflora.
CLAIMS ABOUT RAW MILK AND PASTEURIZED MILK
Raw milk advocates are wont to claim that pasteurization, in addition to killing any pathogens which might be present, also destroys the nutritive value of milk. Nothing could be further from the truth.
Because there is so much misinformation currently circulating about raw milk and pasteurized milk, I developed a presentation which was given at the biennial meeting of the National Conference on Interstate Milk Shipments at Columbus, Ohio in May 2005 by Ms. Cynthia Leonard, M.S., who is a member of my Division. In that presentation, we addressed several of the more common and egregious fallacies about pasteurization that one is presently likely to encounter. Due to the constant and heavy demand for that presentation, we have recently placed it on the FDA website. It can be found at: http://www.cfsan.fda.gov/~ear/milksafe.html.
In addition to the fallacies that we addressed in the presentation, we have been made aware of several other erroneous statements being made by raw milk advocates about raw milk and pasteurized milk and it may be useful for me to address some of these here:
RAW MILK IS NOT A “MAGIC FOOD FOR CHILDREN”
Relatively recently a raw milk advocate has claimed that “Raw milk is a magic food for children”. There is nothing magical about the possibility of contracting foodborne disease from raw milk, having that progress into hemolytic uremic syndrome, ending up having to fight for your young life as best you can and, if you are fortunate enough to survive, having to suffer lifelong complications from your illness, knowing all the while that your life likely has been appreciably shortened as a result of your illness.
Raw milk advocates have mischaracterized scientific literature in the past and indeed, where we have seen them do so, we have publicly pointed out as much previously. Their mischaracterization of the article on the PARSIFAL study (Waser et al) is therefore not at all surprising and indeed the journal article on the PARSIFAL study has been mischaracterized by raw milk advocates since it first appeared. The study is about farm milk and not raw milk. The authors of the study took great pains to explain as much in the Clinical and Experimental Allergy article which they published on the study and indeed the article title even specifies that the report is about farm milk. The authors clearly state within that article that "The present study does not allow evaluating the effects of pasteurized vs. raw milk consumption because no objective confirmation of the raw milk status of the farm milk samples was available." They go on to say that "About half of the parents indicated that they usually did not boil the milk before consumption but no differential effects were observed between those boiling and those not boiling the milk.
This might be a result of biased parental answers or may indicate that pasteurization is not of key importance because compounds other than microbes play a role." They also go on to say that "raw milk may contain pathogens such as Salmonella or EHEC and its consumption may therefore imply serious health risks". Finally, the authors state that "At this stage, consumption of raw farm milk cannot be recommended as a preventive measure." The study does not indicate, as some raw milk advocates claim, that raw milk prevents allergies and asthma in children.
RAW MILK DOES NOT KILL PATHOGENS
The claim that raw milk per se kills pathogens and thus is safe is simply incorrect. Milk contains certain indigenous enzymes to which antimicrobial properties have been ascribed, and milk may contain certain strains of bacteria which might be able to produce anti-bacterial compounds known as bacteriocins, but these enzymes and microbes (if present) do not render raw milk safe. With raw milk, the temperature of storage coupled with the nature and composition of the microflora initially present and simple microbial competition and outgrowth all play an important part in the determination of which microbes will grow and which will not. Some micro-organisms are more fastidious than others. Some do not grow well in cold temperatures, whereas others do. Some pathogens can survive and grow at refrigeration temperatures.
Another version of the claim that raw milk kills pathogens is that “pathogens can multiply in pasteurized milk and other foods but not in raw milk.” That too is untrue. In support of this claim, we have seen raw milk advocates cite a 1982 study by Doyle and Roman (12) and selectively present data from that study which, at first glance, appears to support raw milk advocates’ claim. However, the authors of that study found and reported in that same article that “[s]urvival of the eight Campylobacter strains in refrigerated unpasteurized milk varied greatly.” Furthermore, the authors stated that “one strain of C. jejuni, bovine isolate FRI-CF147B, survived exceptionally well in unpasteurized milk at 4º C. A less than 2-log reduction in cells occurred after 14 days, indicating that under the appropriate conditions, large numbers of campylobacters may survive in raw milk for several days.” The authors also determined that “[i]nactivation of Campylobacter strains in unpasteurized milk paralleled but was greater than the inactivation of strains in sterile milk.” Note that the authors report an inactivation in sterile (not merely pasteurized) milk. Finally, the authors concluded: “The presence and possible persistence of C. jejuni in raw Grade A milk reaffirms the need for pasteurization.” Thus, far from providing a support for raw milk advocates, the Doyle and Roman study clearly advocates pasteurization of raw milk.
PASTEURIZATION DOES NOT DESTROY THE ENZYMES IN MILK
The claim that pasteurization destroys all the “built-in safety systems” or “enzymes that kill pathogens” also is simply not supported by the scientific literature. For example, it has been claimed that pasteurization inactivates lactoferrin. Lactoferrin is an iron-binding protein believed to have dual roles; the one being a facilitator of iron absorption and the other a bacteriostatic role. Paulsson et al (13) determined that “unheated and pasteurized bLf (bovine lactoferrin) preparations showed similar antibacterial properties and caused an effective metabolic inhibition with a moderate bacteriostasis.” They further stated that “pasteurization seems to be the method of choice (when making a lactoferrin product) because it did not alter either the bacterial interactive capacity or the antibacterial activity of bLf.” Tomita et al (14) discussed how a pasteurization process was developed for lactoferrin in order to apply active lactoferrin usage to various products. Plainly, lactoferrin is not destroyed or inactivated by pasteurization.
Similarly, lactoperoxidase, an enzyme which is integral to the lactoperoxidase system of milk preservation, has been described as being ”inactivated” by pasteurization, when actually lactoperoxidase is a very heat stable enzyme which is not destroyed by minimum legal pasteurization conditions, although some literature indicates moderate inactivation. In fact, because it will survive pasteurization intact, measurement of residual lactoperoxidase activity has been proposed as a means of indicating if a heat treatment applied to milk has exceeded high temperature short time (HTST) pasteurization conditions. Contrary to the claim that the lactoperoxidase system can be an alternative to pasteurization, the lactoperoxidase system is not, and could never be an alternative to pasteurization. (Some researchers do consider that it might possibly be used synergistically with pasteurization to extend the shelf life of dairy products).
The lactoperoxidase system, which requires the addition of hydrogen peroxide and thiocyanate ion to milk to be activated, functions as a bacteriostatic mechanism generally, i.e., it serves to keep microbial populations from growing and spoiling milk. It is used in regions of the world where it is difficult, if not impossible, to cool milk, due either to a lack of electricity or cooling equipment or both. It is reported by some researchers to be bactericidal to certain enteric pathogens. Seifu et al (15), in 2005, published an excellent review article on lactoperoxidase, which may be of further interest to this Committee. The claim that lysozyme, which, in conjunction with lactoferrin does have a bactericidal effect, is destroyed by pasteurization is also simply not true. In excess of 70% of bovine milk lysozyme will survive normal HTST conditions, as reported by Griffiths (16).
With respect to indigenous dairy enzymes in general, Stepaniak (17), in 2004, published an excellent review article of the literature available to which I would refer anyone interested in learning what the current science is on the effect of pasteurization on milk enzymes.
Claims have been made by raw milk advocates that Immunoglobulin G (referred to as “IgG antibodies” by raw milk advocates) is destroyed by pasteurization. However, Kulczycki (18) reported in 1987 that his research on bovine IgG suggested “the possibility that pasteurization of milk (and condensed milk) may not destroy the receptor-binding ability of IgG, but instead might enhance its binding by causing aggregation of the bovine IgG.”
PASTEURIZATION DOES NOT CAUSE LACTOSE INTOLERANCE
Raw milk advocates have also claimed that pasteurized milk causes lactose intolerance, (which is an inborn error of metabolism), despite the fact that all milks, raw or pasteurized, contain lactose and that pasteurization does not change the concentration of lactose. A person who is lactose intolerant has a reduced ability to synthesize the enzyme Beta-galactosidase, which hydrolyzes the disaccharide lactose into its monosaccharide constituents, glucose and galactose. Any such person might be expected to experience the symptoms of lactose intolerance when consuming either raw or pasteurized milk.
Recently, a new version of this fallacy has been brought to our attention. A raw milk advocate has begun to claim that raw milk does not cause lactose intolerance because it contains bacteria (which he describes as being “bifido and lacto”) which he believes create their own lactase (beta-galactosidase) when consumed, thus allegedly preventing the symptoms of lactose intolerance. Among the numerous difficulties with this proposition is the fact that the Bifidobacteria in the gastrointestinal tracts of humans are different to those found in animals (Gavini et al) (24) and thus the milk from animals. Furthermore, if Bifidobacteria consumed as a therapeutic or prophylactic measure are to be of any benefit, they must be consumed in appreciable quantities (as might be found, for example in a fermented milk product containing an adjunct Bifidobacteria culture) as well as be of human origin, in order to withstand transit through the intestinal tract (Arunachalam) (25). Finally, it has actually been proposed that the Bifidobacteria present in bovine milk be used as indicator organisms to gauge the extent of fecal contamination of milk.(Beerens et al.) (26). Thus, far from being of any health benefit, the Bifidobacteria present in raw milk are considered by scientists to be an indication of the extent to which it has been contaminated with manure.
Although many potential health benefits have been ascribed to Bifidobacteria in the literature, curing lactose intolerance is not among them. (Arunachalam) (22). De Vrese et al (27) published a useful paper entitled “Probiotics- compensation for lactase insufficiency” wherein they synopsize some of the research done on the utility of Bifidobacteria as promoters of lactose hydrolysis and state that Bifidobacteria “affected lactose digestion less than did lactobacilli or had no effect at all.”
Although we are uncertain just what the raw milk advocate in question is referring to when he mentions “lacto bacteria,” if we assume that he is referring to Lactobacillus species, it is true that several Lactobacillus species are generally considered to be probiotic and that among the possible benefits suggested as being conferred by consumption of fermented dairy products containing appreciable quantities of Lactobacilli are reduced symptoms of lactose intolerance, as reported by De Vrese et al, Holzapfel and Schillinger, McBean and Miller, Savaiano et al. (27, 28, 29, 30) However, Lactobacilli typically are but a small portion of the microflora in milk.
RAW MILK IS NOT A PROBIOTIC FOOD
While making the above claims and perhaps because of them, this same raw milk advocate has recently been describing his milk as being “probiotic.” Raw milk is certainly not a probiotic food, as that term is defined within the FAO/WHO Guidelines for the Evaluation of Probiotics in Food, which was published in 2002 (31), and it is scientifically improper to describe raw milk as being probiotic. That document defines probiotics as being “[l]ive microorganisms which when administered in adequate amounts confer a health benefit on the host”. According to FAO/WHO, in order for that term to be used, stringent requirements must be met, including strain identification, functional characterization, a safety assessment, efficacy studies, and comparison with standard treatments as well as labeling requirements. None of that has been done for raw milk.
PASTEURIZATION DOES NOT DESTROY MILK PROTEINS
Raw milk advocates claim that pasteurization either destroys the proteins of milk or that it renders milk proteins more allergenic, even though the milk proteins that cause allergic reactions (including lactoferrin) in dairy-sensitive people are present in raw milk as well as pasteurized milk. Interestingly, these same sorts of claims were addressed directly over twenty years ago by Coveny and Darnton-Hill (19) when they wrote in their article entitled “Goat milk and infant feeding” that “there are some who feel that pasteurization is unnecessary and even detrimental. Concern appears to centre (sic) on possible increased allergenicity and nutrient losses. However, studies show that the sensitizing capacity of cow’s milk is retained or – more usually – reduced after heat treatment (cites) while pasteurization minimizes the heat destruction of nutrients (cite). There would appear to be little advantage therefore in the use of raw milk.”
Caseins, the major family of milk proteins, are largely unaffected by pasteurization (Farrell and Douglas) (20). Any changes which might occur with whey proteins are barely perceptible.
PASTEURIZATION DOES NOT DESTROY VITAMINS AND MINERALS IN MILK
With respect to vitamins, the claims about the destructive capacity of pasteurization have been many and varied and virtually none of what has been said is accurate.
Milk is a good source of the B-complex vitamins thiamine, folate and riboflavin. Pasteurization will result in losses of each of these of anywhere between zero to 10 percent, which most would consider to be merely a marginal reduction (17), ( 21). Pasteurization does not cause appreciable losses of the fat-soluble vitamins, A, D, E and K (21). Milk does contain a small amount of Vitamin C, but it is not considered to be a good dietary source of that vitamin. Pasteurization will result in a loss of anywhere from 0-10% of the Vitamin C present (21). Most vitamin C losses in milk occur during storage and such will occur whether milk is pasteurized or not.
With respect to the minerals present in milk, raw milk advocates have made several different claims about the allegedly destructive impact of pasteurization. FDA has not been able to substantiate any of these claims. In fact, the scientific literature that we have reviewed thus far contradicts most of the claims being made. Where raw milk advocates indicate that “no significant change” occurs with sodium, potassium and magnesium, FDA would agree, however. Williamson et al. (22) and Zurera-Cosano et al. (23).
RAW MILK IS RAW MILK
Finally, raw milk advocates have recently begun to claim that only raw milk produced at large commercial dairy farms, which is intended to be subsequently pasteurized, is unsafe and that raw milk produced at small farms is safe. The history of raw milk outbreaks, however, does not support such claims. Additionally, literature indicates that somatic cell counts, which are a measure of dairy herd health (with lower counts being better), tend to be lower in larger, high intensity dairy farming operations as reported by Windig et al., Norman et al., Berry et al. and Oleggini et al. (32, 33, 34, 35).
Another variation on this theme that we sometimes encounter is the claim that raw milk is safe if it originates from “certified” dairies. That is simply not correct. As was stated above, in Public Citizen v. Heckler, 653 F Supp. 1229 (D.D.C. 1986), the court was clear in its holding that there existed “overwhelming evidence of the risks associated with the consumption of raw milk, both certified and non-certified." Id. at 1238.
Raw milk is inherently dangerous and should not be consumed. Raw milk continues to be a source of foodborne illness and even a cause of death within the United States. Despite the claims of raw milk advocates, raw milk is not a magical elixir possessing miraculous curative properties. Pasteurization destroys pathogens and most other vegetative microbes which might be expected and have been shown to be present in milk. Pasteurization does not appreciably alter the nutritive value of milk. Claims to the contrary by raw milk advocates are without scientific support. FDA encourages everyone charged with protecting the public health to prevent the sale of raw milk to consumers and not permit the operation of so-called “cow-sharing” or other schemes designed as attempts at circumventing laws prohibiting sales of raw milk to consumers. To do otherwise would be to take a giant step backwards with public health protection.
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