Milk – Nourishing or nasty?

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When M first came home with green top milk ( full fat, raw) I thought it was a step too far.  I eyed the carton suspiciously in the fridge and refused all offers of a cup of tea.  I actually felt I could not physically stomach it and when I tried, the taste was heavy and thick.  M persevered insisting that it was the better choice.  He explained that when you take all the fat out of the milk, you are left with too high a concentration of sugars (Lactose) which interacts with your hormones especially insulin.  As this is exactly what we are trying to avoid on a Paleo style diet it was obvious that if I was going to drink milk, the real natural stuff was the better option.

Nourishing or nasty?

Milk is normally considered to be a food of the agricultural age which is said to have begun approximately 10,000 years ago. However, archaeological evidence indicates that in regions near the Red Sea that fences were used to confine and breed antelopes for their milk more than 30,000 years ago (Schmid, 2003). The Bible makes reference to milk from the earliest times in the Old Testament when God talks to Moses (circa 1500BC) from the burning bush he promises to lead the Israelites from slavery to a land of abundance and promise, a ‘land flowing with milk and honey’. This indicates that people of the day treasured milk and that a land that had this in plentiful supply was a desirable place to be. Milk and other dairy products have long been used by man and treasured in numerous cultures around the globe for their nourishing properties and ability to sustain life.

Weston A Price visited the native Swiss villagers in the Loetschental valley and found them in impressive health (Price, 1945). They had treasured and reared healthy herds of cattle that provided one of their vital foods, milk and the butter made from it. Dr Price also discovered the Masai in Kenya lived with milk as one of their central foods. The cow has been considered sacred in India and surrounding regions for generations. Cattle were free to roam around the temples where milk was used to make their most sacred food, ghee or clarified butter. Milk was prized as a nutritious food throughout Europe, the Middle East, East Africa and in many regions of Asia. The tide has turned on milk in recent years with the increase in dairy and lactose intolerance. Negative food reactions have caused many to exclude milk from their diets. Others have raised concerns that many populations throughout the world have not traditionally had milk available to them and so will not likely tolerate dairy produce. This is an unusual argument as there are many foods that are not traditionally available through the world, but that does not mean they cannot be eaten outside their traditional country of origin. This logic would negate the intake of tropical fruits and fish in temperate zones and vice versa.

Lactose intolerance throughout the population has been estimated to be 12-13% (Nicklas, 2009). Within smaller ethnic groups the levels of lactose intolerance have been estimated at much higher levels. 70% of African Americans, 74% of Native Americans and 53% of Mexicans have been identified as having a degree of intolerance (Lipski, 2005). Lactose intolerance across a percentage of the population is not a reason to generalise that the population should stop drinking milk. The same logic could be applied to wheat, peanuts, soya or any other food that commonly brings on allergic reactions and are widely eaten. It is obvious that those who suffer from these reactions to milk should probably avoid the source of this aggravation for a period of time or perhaps in severe cases even the indefinite future. Continual drinking of milk will only serve to further inflame the sensitive gut wall increasing the spaces within the tight cellular junctions and allowing partially digested proteins and sugars to get into the blood stream. These are recognised as foreign and the body initiates an immune response to these foods and the level of intolerance increases (Lipski, 2005). Despite this it must be understood that lactose intolerance is the result of enzymatic deficiency rather than an allergic reaction to milk. The lack of the enzyme lactase is a result of pasteurisation. Unpasteurised milk does not suffer this heat treatment and as such has a plentiful supply of lactase to help in the digestion of lactose. It is often the case that those who suffer lactose intolerance can actually enjoy raw milk because the enzymes are present in the milk.

Milk allergies are primarily caused by the inability to digest certain proteins. Approximately 30% of the proteins in milk are the beta casein variety. In the past the cows that were used to supply the majority of milk were traditional breeds like Jersey and Guernsey which contain the original A2 type of beta casein in much higher amounts. The dominant breeds of modern dairy cattle today are high milk yield breeds like Holstein (Fresian) which have developed a genetic variant called A1 beta casein found in much higher concentrations than A2 protein. Beta caseins contain opioid peptides called  casomorphins and one in particular has been implicated in many health problems. Beta casomorphin 7 (BCM7) derived from A1 dominant milk has been linked to increases in oxidised LDL cholesterol, a heart disease risk factor, it has a negative impact in insulin formation and causes increased histamine response in humans which trigger allergic reaction (www.betacasein.org, 2007). The huge increase in modern dairy breed milk with higher levels in A1 beta casein and the resulting BCM7 may be one the reasons for increasing rates of dairy allergies. Lower levels of allergic reaction are likely to be found in milk with higher levels of A2 beta casein from traditional breeds such as Guernsey and Jersey. If this A2 rich milk is unpasteurised it is even more unlikely to cause problems.

The majority of modern milk has passed through industrial dairies where it undergoes skimming, pasteurisation, standardisation and homogenisation. These processes bring about significant change and alter many of the nutritious and beneficial properties of raw milk. Pasteurisation is the process of passing the milk between steel plates and heating the milk to 72°C for between 20-30 seconds. This is done as a measure of health and safety to ensure no pathogenic bacteria have contaminated the milk prior to human consumption. This temperature does kill off the majority of harmful bacteria and also all of the beneficial bacteria like lactobacillus acidophilus. Milk contains about 13% solids of which a little more than 30% represent proteins. 80% of milk proteins are caseins and the remainder are whey
proteins. These proteins provide the full spectrum of necessary amino acids for good health and have always been shown to be highly digestible and bioavailable. Pasteurisation occurs at temperatures that are too high causing structural change of many protein molecules rendering them biologically inactive. Enzymes found in milk, such as lactase necessary for the digestion of lactose sugars, are also denatured during pasteurisation and can no longer function. Loss of functional lactase in pasteurised milk is likely to be another reason why many today shows signs of lactose intolerance.

Milk is subjected to centrifugal force to separate the fat from the liquids. All fat is removed from all milk within the dairy and then standardised amounts of fat are added back in exact amounts to provide whole (3.25-3.5%), semi-skimmed (1.8-2.0%) and skimmed or non fat milk (0.1%). Whole milk most closely resembles the original milk, but has been reconstituted as have all industrially processed milks (Schmid, 2003). The removal of fat alters the texture so dried skimmed milk powder is added to restore this. Milk powder dried through the use of large spray dryers at temperatures that exceed 80°C have more denatured proteins and oxidised cholesterol that has been implicated in the build up of arterial plaque. Homogenisation follows the standardised addition of cream back into the milk. Milk is forced through tiny holes at high pressure which breaks down the fat globules into minute particles that become suspended within the milk and do not gather and  settle on the surface. ‘Big dairy’ claims that homogenisation is a result of consumer pressure and that the public do not like to see a cream line on the milk. However, pasteurisation and homogenisation also solved some of the challenges of distributing milk. Pasteurisation greatly increases the shelf life of the milk and homogenisation prevents the cream settling and sticking to the inside of the milk tankers during long journeys.

Traditional breeds of cattle produce milk with a fat content between 4-8% when they are grass fed. Standardisation of milk removes significant amounts of cream which would then be visible in a much smaller cream line in non-homogenised milk, indicative of lower quality milk. Homogenisation prevents the cream line from ever forming and so serves to hide the reduced fat content and lower quality of modern milk. Butterfat removed during standardising is also of greater financial value to the dairy sold as butter, cream and ice cream. Dairy processing ultimately destroys beneficial bacteria, bioactive enzymes, denatures proteins, oxidises some vitamins including vitamin C and it decreases calcium availability.

Although cow’s milk is the most common sheep and goat’s milk is also consumed fairly regularly as alternatives to cow’s milk. Some find goat’s milk easier to digest due to its lower casein and higher whey content and greater levels of short and medium chain fatty acids. Sheep milk is considerably higher in fat with a greater amount of saturated fats than either cow’s or goat’s milk. Cow’s and goat’s milk have about 121mg of sodium per cup (Mateljan, 2007) and as such represents a low sodium food containing a very small amount of the 6g per day recommended intake.

Imitation milks have also been gaining ground in the dairy market place with the increasing number of people reporting lactose intolerance or milk allergies. These imitation products include soy, rice, oat and almond milk. Technically they are not milks at all as they are not drawn from the mammary gland of an animal. Beans, grains and nuts are used to flavour water and generate a form of beverage that may in some ways resemble milk. A considerable amount of money has been invested in processing methods to more closely imitate the taste, texture and flavour of real milk. Soy is by far the most popular imitation milk with sales in excess of $1billion in the United States (Daniel, 2007) and £250 million in Western Europe in 2005 (Food Navigator, 2005). Modern soy milk production includes pre-soaking in bicarbonate of soda solution, high temperature pressure cooking, chemical deodorising to remove the strong smell, added sugar or syrup to sweeten and added flavours to cover the strong bean taste. Processing nutrient damages include vitamin losses, denatured proteins, oxidised  polyunsaturated fatty acids and rancid lecithins (Daniel, 2007). Soy and imitation milks are very different from natural milk and will not lead to optimal health despite marketing efforts to highlight the apparent health benefits and similarities to real milk.

Milk ultimately is a naturally occurring and nutritious food, but modern processing and technological adjustments have reduced its value for human consumption and may even be introducing problems of digestibility and allergic reaction. The best way to consume milk is to use it whilst it is in it’s most nourishing and digestible form – raw, unpasteurised, non-homogenised and full fat! Providing it comes from high quality farms with careful, discerning famers, unpastuerised milk can be a nutritious and significantly beneficial part of a nourishing dietary plan. Seek out recommended farmers and milk suppliers here: unpasteurised milk suppliers

Related articles

• Lactose: How Much Can You Take? (webmd.com)
• http://thebovine.wordpress.com/2008/10/28/