A2 milk is a variety of cows' milk that predominantly contains the A2 form of β-casein proteins (as opposed to A1 milk, which contains mostly A1 β-casein proteins). Cows' milk like this was brought to market by The a2 Milk Company and is sold mostly in Australia, New Zealand, China, and the United States. It was sold in the United Kingdom between 2012 and 2019. Non-cow milk, including that of humans, sheep, goats, donkeys, yaks, camels, buffalo, and others, also contains mostly A2 β-casein, and so the term "A2 milk" is also used in that context.
The a2 Milk Company and some companies producing goat's milk products claim that milk containing A1 proteins is harmful, but there has been no widely accepted scientific work identifying a link between A1 protein and any adverse effect on health.
A1 and A2 beta-casein are genetic variants of the beta-casein milk protein that differ by one amino acid. A genetic test, developed by the a2 Milk Company, determines whether a cow produces A2 or A1 type protein in its milk.
History In the 1980s, medical researchers began to explore whether some peptides (including peptides from casein) that are created during digestion might have negative or positive health effects.
Interest in the distinction between A1 and A2 beta-casein proteins began in the early 1990s via epidemiological research and animal studies initially conducted by scientists in New Zealand, which found correlations between the prevalence of milk with A1 beta-casein proteins in some countries and the prevalence of various chronic diseases. The research generated interest in the media, as well as among the scientific community and entrepreneurs. If it were indeed true that BCM-7 is harming humans, this would be an important public health issue, as well as a commercial opportunity.
Cow milk is about 87 percent water and 13 percent solids, a combination of fat, carbohydrates in the form of lactose, minerals, and protein. About 30 to 35 percent of the casein (equivalent to two teaspoons per quart of milk) is beta-casein, of which there are several varieties, determined by the genes of the cow. The most common of these variants are A1 and A2 proteins, named for the order in which they were identified by scientists. The sole difference is that one of the 209 amino acids that make up the beta-casein proteins, a proline, occurs at position 67 in the chain of amino acids that make up the A2 beta-casein, while in A1 beta-casein, a histidine occurs at that position.
Studies in cells found that digestive enzymes that cut up proteins interact with beta-casein precisely at that location, so that A1 and A2 beta-casein proteins are processed differently. A seven-amino acid peptide, beta-casomorphin-7, can be cut away from the A1-beta-casein protein by those enzymes, but the enzymes cannot cut the A2 protein at that location, so BCM-7 is not formed from A2 proteins.
Studies in humans have not consistently found that BCM-7 is formed in the human digestive system. BCM-7 can also be created during the fermentation of milk or through the process by which cheese is made; those same processes can also destroy BCM-7.
Scientists believe the difference originated as a mutation that occurred between 5,000 and 10,000 years ago—as cattle were being taken north into Europe—when the proline at position 67 was replaced by histidine, with the mutation subsequently spreading widely throughout herds in the Western world through breeding.
The percentage of the A1 and A2 beta-casein protein varies between herds of cattle, and also between countries and provinces. While African and Asian cattle continue to produce only A2 beta-casein, the A1 version of the protein is common among cattle in the western world. The A1 beta-casein type is the most common type found in cow's milk in Europe (excluding France), the US, Australia and New Zealand. On average, more than 70 percent of Guernsey cows produce milk with predominantly A2 protein, while among Holsteins and Ayrshires between 46 and 70 percent produce milk containing both the A1 and A2 proteins.
A2 Corporation
The A2 Corporation was founded in New Zealand in 2000 to commercialise a genetic test to determine whether a cow will produce milk without the A1 protein, and to market the milk it produces as A2 or A2 MILK.Australian Broadcasting Corporation. 31 March 2003 Transcript of "White Mischief" , an episode of Four Corners, an investigative journalism series.Staff, New Zealand Herald. 14 May 2001 A2 protein milk supply on horizon In 2003, A2's website said: "Beta casein A1 may be a primary risk factor for heart disease in adult men, and also be involved in the progression of insulin-dependent diabetes in children" and the CEO had linked A1 to schizophrenia and autism. A2 Corporation also petitioned the Food Standards Australia New Zealand regulatory authority to require a health warning on ordinary milk.
The company initially marketed its milk as containing no A1 protein, but in 2003 the New Zealand Commerce Commission tested the milk and found some A1 protein in it, and forbade the company from saying the milk had no A1 protein. The commission notice of the ruling said: "Although the A2 Corporation expressed confidence during the investigation that its quality controls were sufficient to exclude the vast majority of beta casein A1, it acknowledged that it could not be certain that there was no A1 in A2 milk."
In April 2014, A2 Corporation changed its name to The a2 Milk Company Limited, and at that time had about 8% market share of the milk products market in Australia.Press Release, A2 Corporation. 31 March 2014 A2 changes name
"A2 MILK" are trademarks held by the A2 Milk Company.
Commercial production and sale A2 Corporation licensed patents filed in the 1990s by the New Zealand Dairy Board, and filed its own patents on genetic tests to determine what form of beta-casein cows produce in milk, and concerning supposed adverse health consequences of milk containing both the A1 and A2 proteins.EP0789842A1 Google patentsPhilippa Stevenson for the New Zealand Herald. 21 December 2000 A2 Corp pays $8m for milk patent rights
Australia and New Zealand The a2 Milk Company focused its initial efforts on urging farmers to undertake breeding programs to develop herds that would produce milk with predominantly A2 protein. The launch of the milk was delayed by opposition from Fonterra, which had contracts with about 98% of New Zealand dairy farms. These contracts were protected under New Zealand law by the Dairy Industry Restructuring Act of 2001.
Seeking leverage in the battle with Fonterra over access to farmers, and over patent rights, Howard Paterson, the CEO of A2 Corporation, led the company into litigation against Fonterra, asking the New Zealand High Court to order Fonterra to put health warnings on its conventional milk concerning risks of type 1 diabetes, heart disease, autism and schizophrenia due to the presence of A1 beta-casein, and to force Fonterra to publicly disclose all the information it had about the links between A1 beta-casein and health risks.Deborah Hill Cone for Share Chat 1 November 2002 A2 accuses dairy giant of suppressing milk defects Quote: "The lawsuit risks inflicting catastrophic damage to New Zealand's international reputation and foreign earnings as Fonterra turns over $14 billion and makes 20% of the country's total offshore receipts. As if that would not be enough of a PR disaster as the country tries to maintain its position as a clean, green food producer...."
The litigation threatened New Zealand's economy and international reputation as at the time Fonterra was responsible for 20% of New Zealand's exports. The press over the litigation and public concern over the claims of A2 Corporation led the New Zealand Food Safety Authority and the Ministry of Health and the Food Standards Australia and New Zealand to issue reports and statements confirming the safety of conventional milk.Office of the Minister of Food Safety, New Zealand Food Safety Authority. 27 November 2007 A1-A2 Milk: Arrangements for Upcoming Reviews
A2 Corporation obtained agreements with enough dairy farmers to launch its milk in New Zealand at the end of April 2003.New Zealand Stock Exchange. a2 Milk Company Overview In the middle of 2003, both founders of the company died. In July, Paterson was found dead in his hotel room during a business trip at the age of 50.Staff, New Zealand Herald. 5 July 2003 Obituary: Howard Paterson A month later Dr. Corran McLachlan died of cancer at the age of 59. In New Zealand it is illegal to make health claims about a food product without providing scientific evidence and registering the food as a medicine, and in November 2003 the New Zealand Commerce Commission advised that A2 Corporation Ltd and its licensed a2 MILK brand producers had agreed to amend the health claims in their promotional material following a warning from the commission. By end of 2003 the weakened A2 Corporation had withdrawn the litigation against Fonterra and negotiations had resumed.
Meanwhile, the first time milk with predominantly A2 protein was marketed anywhere in the world was in March 2003 in Australia, by a dairy farm unaffiliated with A2 Corporation, run by the Denniston family. Shortly thereafter, an Australian company called A2 Dairy Marketers licensed patent rights and the A2 trademark from A2 Corporation and started offering Australian dairy farmers a premium price for their milk, if it was shown to be pure A1 protein-free milk. The Dennistons and A2 Dairy Marketers marketed milk with predominantly A2 protein boldly, touting its safety and the dangers of standard milk. However, Australian laws forbid companies from making misleading health claims about food and, in September 2004, A2 Dairy Marketers in Australia was fined $15,000 after it pleaded guilty to six breaches of those laws.Staff, New Zealand Herald. 28 April 2003 A2 milk launched in NZ, outside Fonterra's structure
The company, which had been in a tenuous financial situation since beginning trading in May 2004, went into administration in October, and was liquidated in November, owing farmers and processors tens of thousands of dollars.Shelley Lloyd for the Australian Broadcasting Corporation. 17 November 2004 A2 milk liquidates A $1.27 million federal government grant awarded to the company in August as part of the Regional Partnerships Program was also cancelled.Australian Senate finance and public administration references committee report on Regional Partnerships and Sustainable Regions programs, October 2005, pages xiv, 97–100 A2 Corporation set up a new subsidiary and licensee, A2 Australia, to market and produce its product. A2 Australia established new contracts with the dairy farmers who had A1 protein-free herds, promising better payment terms — a week in advance instead of once per month, after shipment.
In December, A2 Corporation sold its interests in A2 Australia to Fraser & Neave, a food marketing giant in Asian markets, for about $1.1 million. A2 Corporation had lost about $1.3 million for 2004, the same as it had lost the year before; the sale allowed A2 Corporation to rely on Fraser & Neave to build the Australian and Asian businesses.Ellen Read for the New Zealand Herald. 30 December 2004 Quick sale likely for A2 Corp A2 Corporation focused on recovering from the deaths of its founders organizationally and financially, relied on its New Zealand licensees to develop the New Zealand market, and turned its focus to developing overseas markets.
As A2 Corporation grew its business, opposition to A2 Corporation's claims played out in the media. Dairy Australia, the national association of the Australian dairy industry, and market competitors like Parmalat have consistently said that there is no evidence to suggest A1 proteins are dangerous and have warned that criticism of normal milk is damaging the entire dairy industry.