Below is an article written by Ben Pratt of Natural Food Finder, this has been kindly reproduced with his permission, Thanks Ben!
An article titled ‘The raw milk revolution’ was published on the Guardian newspaper on Wednesday 23rd November 2011. It was focused on the growing interest in this historical and valuable food and was not intended to be a convincing argument for the safety of raw milk. I decided to post some comments in support of Jon Healey the author of the article who had traveled to Olive Farm to taste the high quality milk from the Hurdlebrook herd of Guernsey dairy cows. We previously reported on the quality and cleanliness of the farm on an early blog on this site. We have also discussed the issue of whether there is nutritional benefit to raw milk versus pasteurised milk in a previous blog.
I was pleased to see that many of the early comments posted with this article were fairly positive, but invariably the further I read the more I found the nutrition zealots of the world banging on about raw milk is risky to drink, you would be risking your health to do so, it is like playing Russian roulette with your health etc. etc. etc. I could not stand the falsehoods anymore and so posted some replies to these individuals who seemed to have a desire to paint the whole raw milk picture with the same black brush. The comments and points raised in the day or two that followed have urged me to write a blog on the safety of raw milk. So here goes! Is raw, unpasteurised milk safe to drink?
The primary issue surrounding raw milk safety is whether or not milk that is not pasteurised carries with it harmful bacteria that may cause illness or in severe cases hospitalisation? Let’s start off by being brutally honest. Raw milk does have a risk of contamination from harmful bacteria…but then so does all food! All food is likely to carry bacteria into our digestive tract, whether it was brought from the farm, the processing plant or simply comes into contact with a less than sterile kitchen surface. Much of the bacteria that will be in food is not pathogenic, it will do us absolutely no harm. in fact some bacteria will be beneficial. Humans have developed a symbiotic existence with the many trillions of bacteria that live around us and in us. The healthy human bowel is estimated to have 3-4 lbs of bacteria within it. So first and foremost we need to get over the assumption that all bacteria are harmful and therefore we must kill 99.9% of germs with our sprays and cleansers, nevermind our food. However, all food does carry a small chance of exposure to a few species of bacteria that can cause illness and harm. A couple of dozen, out of the many millions of bacterial sub types, are potentially harmful. There are four specific families of bacteria that are responsible for a large majority of the food poisoning in modern societies:
We need to determine whether these pathogenic bacteria are rampant in the milk supply or not? A study of raw milk risk in the USA conducted by Dr Ted Beals evaluated the actual incidence of bacterial infection from the ‘big four’ bacteria as a result of drinking unpasteurised milk. This was compared to the total number of cases of food poisoning from all sources across the nation from each specific bacteria over same time period. The figures he determined are as follows:
This hardly sounds like the dreaded, bacterial epidemic that is usually thrown by dissenting voices at those who drink raw milk. Dr Beals states that he tried to ensure that he included all certain cases of raw milk contamination in his figures from the 10 year sample he selected. Clearly food poisoning is a real problem in the USA, with so many reported cases of illness on record, it is definitely something that needs to be dealt with. However, if raw milk is causing such a small number of annual cases of illness, then what is causing the problem?
Whilst this data set does acknowledge that bacterial infection can be traced to raw milk, it does not paint the whole picture. This table needs to be put into context by looking at other studies that investigated the rate that food poisoning occurs within other food categories. The following data is drawn from a scientific study that investigated the rates of campylobacter infection from a random sample of food poisoning cases in the USA. They determined that the highest fraction of food poisoning came from chicken (31%), eating raw, salad vegetables (21%), drinking bottled water (12%) and eating fried chicken (4%). Campylobacter infection from all milk sources in this study was miniscule in comaprison to these other much more potent sources (Evans, Ribeiro & Salmon, 2003). Indeed some studies have shown that over time the natural and living compounds in raw milk actually destroy and kill off harmful bacteria over time rather than allow harmful bacteria to grow.
- Lactobacillus gradually increase the lactic acid levels in the milk, altering the pH which slows and even helps reverse pathogenic bacterial growth
- Lactoperoxidase, which is much higher in cows and goats milk than human milk helps to disarm and destroy pathogenic bacteria
- Lactoferrin is found in rich supply in raw milk and has potent anti-bacterial properties and has even been approved by the American FDA for use as an anti-microbial spray against E-coli 0157:H7 in meat processing plants because it is so effective
- Many other compounds in raw milk have an anti-microbial effect such as medium chain fatty acids (MCFA), enzymes (lysozyme), fibronectin and glycomacropeptides to name a few
All of these protective mechanisms are destroyed above 56 degrees celcius (bar the MCFA’s) and as the pasteurisation process heats to 72 degrees, they are completely inactivated by subjecting milk to this process. Therefore, milk that has been pasteurised becomes sterile, but if a pathogenic bacteria does manage to infiltrate the system it has nothing to stop it replicating and spreading like wildfire through the milk. This will then be dangerous to drink as the chances of illness are greatly increased and the milk has no protective factors! Interestingly, it was reported in Letters in Applied Microbiology (1999) that when 7 strains of E-coli 0157:H7 were added to raw milk at concentrations of 1 million per ml that the bacteria failed to grow and gradually died off. I am not suggesting we should not care about the purity of our raw milk, but this does show us that the protective factors in raw milk fight pathogenic invasion.
The Foods Standards Agency has stated that there has not been a single case of reported illness in England or Wales as a result of drinking raw milk since 2002. During the last 10 years the popularity of drinking unpasteurised milk has grown considerably, but the rate of bacterial illness has not increased with the rise in intake. Organic Pastures Dairy in California operates a much larger raw milk operation than most small family farms. They have produced over 40 million servings of raw milk since 1999 without a single episode of food poisoning or illness and without a single bacterial lab test resulting in a positive outcome. California regulates raw milk sales and demands that there are no more than 15,000 bacteria per millilitre. Organic Pastures dairy currently averages 569 bacteria per millilitre, far below the allowable limit. Their milk is clean as a result of high standards of animal husbandry and hygienic milk processing facilities.
Unpasteurised milk is also regulated in the UK. Farmers selling raw milk to the public must hold a license to do so and their milk must be tested at least quarterly. Dairy herds must also be completely TB and Brucellosis free. It is also common to find raw milk farmers ensuring their cows are fed on grass, hay and silage in preference to concentrated feeds to ensure they keep them as healthy as possible. A farmers business relies on his raw milk sales. He cannot afford to be lax in his standards as a single case of illness as a result of drinking raw milk would destroy his business. This powerful motivation keeps the standards of farming high and the milk production system clean.
It is perfectly acceptable to have regulations governing raw milk production. It is important to ensure that standards are maintained and the risk to the public is kept at a minimum. However, it seems grossly unfair that such a strict eye is kept on raw milk, whilst other foods that are currently delivering a much greater portion of the food poisoning episodes in modern society are not subject to the same level of scrutiny. With raw salad vegetables contributing a sizeable portion of illness, should we not be arguing for a tighter regulations on these foods being consumed raw? That would only be fair! If you think this is ridiculous then consider the faulty logic behind the long held belief that raw milk is somehow inherently more dangerous to consume than other raw foods!