We have always heard that drinking milk is very important for our overall health. After all, milk is fortified with a range of vitamins including,  vitamin B2 and B12, vitamin A and D, as well providing a source of calcium, pantothenic acid, selenium, biotin and protein which can aid our general health.  But is the milk that we are purchasing from the supermarket truly the best for our bodies? What are some of the processes that this type of milk goes through? Are they safe for us? What health implications are there? Let’s take a look.


Most of the milk you see on the supermarket shelf is both pasteurised and homogenised and a lot of people don’t understand the difference between the two.  Pasteurisation is a process that most people are familiar with. This process quickly heats and then cools the milk to kill harmful microbes and germs in milk. It is illegal to sell unpasteurised (raw) cow’s milk in Australia for human consumption¹.  You may not be all that familiar, though, with the process that is called homogenisation. Homogenisation has been practice by most dairies since the early 20th century and it’s purpose is to break down fat molecules in milk so they don’t separate. Without homogenisation, fat molecules in the milk rises to the top and forms a layer of cream. This was the only type of milk that was available to our grandparents when their milk was delivered in glass bottles back in the day.

Homogenised versus Non-homogenised Milk

So what’s the difference and why should you care? Basically, pasteurisation is intended to make milk safer for human consumption and government agencies all over the world claim it doesn’t reduce nutritional value, while you’ll find many people pro “raw milk” will disagree. However, homogenisation on the other hand is not needed for safety, but rather for consistency and taste for the consumer.

Homogenisation is a mechanical process and doesn’t involve any additives. And much like pasteurisation, arguments exist for and against it. It’s advantageous for large-scale dairy farms to homogenise milk because the process allows them to mix milk from different herds without any issues. By preventing cream from rising to the top, homogenisation also leads to a longer shelf life which is attractive to consumers and also allows large farms to ship greater distances and do business with more retailers. Finally, homogenisation makes it easier for dairies to filtrate out the fat and create two percent, one percent and skim milk.  But as with most mechanical processes, when you homogenise milk, you not only change the size of the fat globules, you also rearrange the fat and protein molecules—which could alter how they act in the human body.

As with a lot of inventions and processes today, it was what I call a “convenience evolution”, whereby the consumer got lazy (shaking a milk bottle vigorously obviously required some effort!), wanted it to last longer in the fridge and got concerned with their waist line so needed reduced fat milk.  Good old farmer Joe, responded with homogenised milk!

New Research

New research shows us that homogenisation is not always a good thing. The process itself reduces the size of fat molecules in the milk. With smaller fat molecules, the fat may be easier for your body to absorb. The size of protein molecules in homogenised milk are also reduced, meaning this protein is not absorbed, but simply passed through the body. This means that even though we have always been told that milk was healthy, homogenized milk could be contributing to weight gain and poor nutrition. It could also be contributing to the hardening of arteries and other heart issues. Many types of homogenized milk also contain harmful added hormones. In some research, these hormones themselves have been linked to issues like cancer.

Robert Cohen (Executive Director of the Dairy Education Board) wrote in his article “Homogenized Milk: Rocket Fuel for Cancer”²

“Homogenization is the worst thing that dairymen did to milk. Simple proteins rarely survive digestion in a balanced world. 

Milk is a hormonal delivery system. With homogenization, milk becomes a very powerful and efficient way of bypassing normal digestive processes and delivering steroid and protein hormones to the human body (both your hormones and the cow’s natural hormones and the ones they were injected with to produce more milk). 

Through homogenization, fat molecules in milk become smaller and become ‘capsules’ for substances that bypass digestion. Proteins that would normally be digested in the stomach or gut are not broken down, and are absorbed into the bloodstream…

Homogenized milk, with its added hormones, is rocket fuel for cancer.”

Other issues with milk

Cow’s milk allergies are one of the most common allergies (it’s number one in the US) and it has been well documented that it can cause everything from diarrhoea, cramps, bloating, gas, skin rashes, acne to gastrointestinal bleeding, iron-deficiency anaemia and atherosclerosis.  According to Dr Mercola, it is also the primary cause of recurrent ear infections in children and has been linked to insulin dependent diabetes, rheumatoid arthritis, infertility, and even leukaemia³.

In the 1970s, Kurt Oster suggested that homogenised milk might actually increase the risk of heart disease. His opinion was based on the hypothesis that homogenisation changes the size of fat globules in milk and this in turned changed the molecular structure of fats and protein and therefore may in fact alter how our bodies react to it.  Further studies into this theory have not reached the same conclusion Kurt Oster did.

Something to note – most animals are exclusively breast-fed until they have tripled their birth weight, which in human infants occurs around the age of one year. In no mammalian species, except for the human (and domestic cat) is milk consumption continued after the weaning period. Calves thrive on cow milk. Cow’s milk is designed for calves. Not humans.³

I have never been a big consumer of cows milk, instead opting for dairy free options such as almond or coconut milk.   When I do buy it, I buy Organic Lactose Free, Non- Homogenised Milk.  If you love your cow’s milk, do some more research and consider purchasing un-homogenised milk.  In my opinion, the less processing involved with something we consume, the better we are!

  1. http://www.foodsafety.asn.au/resources/unpasteurised-milk-and-cheese/
  2. http://www.health101.org/
  3. http://www.mercola.com/article/milk/no-milk.htm