Current Progressive Dairy digital edition

The power of milk

John Lucey for Progressive Dairyman Published on 31 March 2017

With nine essential nutrients and 1 gram of protein per ounce, milk provides outstanding nourishment with every sip. Perfected by nature over millennia, milk and its byproducts have long been studied by nutritionists and food scientists alike.

Over the years, these studies have shown that milk offers a wide range of highly bioavailable nutrients that are needed for every stage of life.



Whether the consumer is interested in muscle recovery, vitamins and minerals for growth, the health benefits of conjugated linoleic acid (CLA) or the satiety of a high-protein beverage, milk provides these functions as well as key nutrients.

In fact, milk is the only food nature designed to be a complete nutritional package that can sustain and grow infants until they are old enough to eat other foods. The more milk is studied, the more complex and fascinating we find the array of different types of naturally created nutrients.

Recent trendy non-dairy “milks” have been created with a variety of ingredients, stabilizers and added sugars, but these alternatives lack the natural nutrient diversity of milk.

For consumers that are lactose-intolerant, nowadays there are a wide range of lactose-free dairy products available so individuals can still gain the benefits of dairy for their concerns, like bone health, and not have to worry about any digestion issues.

At a basic level, milk is composed of water, fat, protein, lactose and minerals. While water accounts for about 87 percent of milk’s composition, making it a hydrating beverage, it is the proteins, fats, vitamins and minerals that make milk a truly unique product.


In terms of minerals, milk contains calcium, magnesium, phosphorus, iron, potassium, sodium and zinc, which together aid in bodily functions such as metabolism, skeletal development and the synthesis of proteins.

The lactose and vitamins in milk, including A, D, B12, riboflavin and niacin, are also all associated with vital functions such as the intestinal absorption of calcium and a healthy immune system.

The proteins and fat in milk are of particular interest, however, as recent studies have showcased the unique benefits of the specific types of fats and proteins naturally found in cow’s milk.

Milkfat contains over 400 different types of fatty acids, which contribute greatly to the rich, creamy mouth feel of milk. Perhaps most interesting, however, is the recent science which shows that, contrary to earlier beliefs, milkfat may actually aid in the prevention of heart disease and reduce the risk of obesity.

CLA is one of the fatty acids that has been linked to the beneficial impact of dairy fat consumption. Sometimes called rumenic acid, CLA is most prevalent in the milk and meat of pasture-fed ruminant animals, making grass-fed cow’s milk an excellent source of CLA.

While there is still much to learn about CLA, many studies have already pointed out its potential in reducing the risk of coronary heart disease as well as some types of cancers.


The protein in milk is another area of interest, especially for food scientists. From its ability to provide satiety (feeling full or not hungry) to its unique amino acid profile, the protein in milk is, on its own, a reason to consume this exceptional beverage.

Milk contains two types of proteins: casein and whey. Casein, which generally makes up about 80 percent of the protein in milk, is a slowly digested protein that is rich in calcium and phosphate, which means these nutrients will be absorbed steadily throughout the day.

Whey, on the other hand, is more quickly absorbed but is equally important due to its high levels of essential amino acids.

Sometimes called the building blocks of life, branched-chain amino acids aid in energy production and protein synthesis. These specialized amino acids are considered to be essential amino acids because they cannot be made in our bodies and must be obtained through diet.

Luckily, whey protein contains extremely high levels of many branched-chain amino acids including leucine, which has been linked to muscle protein synthesis and muscle recovery after exercise.

While a tall glass of milk is a great start to any day, milk’s unique nutritional benefits can also be enjoyed on a more individualized basis, or in a wide range of products, thanks to food science.

In fact, it was in part the high levels of branched-chain amino acids found in milk that motivated food scientists to develop ways to fractionate milk in order to harness the individual benefits of these proteins, minerals, fats and vitamins.

Fractionating milk mostly involves simple filtration procedures that allow for the separation of important milk components like whey protein. Three of the most well-known dairy powder products of this filtration process are milk protein concentrate, whey protein concentrate and whey protein isolate.

These byproducts of milk are widely used in protein drinks, sports nutrition powders, power bars and many more. For example, milk protein concentrate 85 is about 85 percent protein (dry basis), 3 percent lactose, 7 percent minerals and 1 percent fat.

Whey protein concentrate 80, on the other hand, is typically about 80 percent whey protein (dry basis), 4 percent minerals, 9 percent lactose and 6 percent fat, while whey protein isolate is around 92 percent protein (dry basis), 2 percent lactose, 3 percent minerals and 1 percent fat.

It is worth noting that whey protein concentrate and whey protein isolate are the highest known sources of the muscle-synthesizing branched-chain amino acid leucine, making them an excellent choice for athletes or active individuals.

In addition to the proteins, manufacturers can also fractionate milk in order to isolate the minerals. This process most often leads to a product called permeate, which has proven to be an excellent salt replacer in various foods like soups and baked products thanks to its salty flavor.

Another added benefit of permeate is that it reduces the consumer’s sodium intake while contributing a nice dairy flavor to the food product.

While this only skims the surface of milk’s benefits, there’s no denying the nutritional value of milk. Thanks to ongoing dairy farmer-funded research and the overall support of the dairy industry, scientists are continuing to discover the unique power and benefits of milk.  end mark

John Lucey
  • John Lucey

  • Director
  • Wisconsin Center for Dairy Research
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