Why Skim Milk Isn’t as Healthy as You May Think

February 22nd, 2010

We’ve been told for years that skim milk and low fat milk are healthier choices than whole milk, but is this really the case? While this advice is mostly based on avoiding saturated fat, there are other important factors to consider as well.

Milk is the primary source of nutrition for young mammals before they’re able to eat and digest other types of food. It’s an excellent source of protein, vitamins, and minerals, all of which are critical to proper development. This applies to the fat content of milk as well. When the fat is removed, so is a portion of its nutritional quality and its ability to support healthy development. The recommendation to avoid milk fat is not only based on questionable science, but is also influenced by the profit based motives of the dairy industry.

Could Nature Be This Inconsistent?

Despite the common misconceptions about heart disease, the saturated fat and cholesterol in milk have important benefits. Although we’re the only mammals that consume milk as adults and also from other species, it’s obvious that milk provides the optimal mix of nutrients for human development and is the result of millions of years of development.

Heart disease is a leading cause of death worldwide, and despite a lack of supporting evidence that can withstand unbiased scrutiny, saturated fat and dietary cholesterol have taken much of the blame. It’s highly unlikely that the very same nutrients that are so critical to human development can be so deadly later in life. In fact, research including the work of Dr. Weston A. Price has shown the opposite to be true. His work, completed in the 1930s, describes the health of a number of isolated cultures that consume significant amounts of saturated fat and cholesterol from a variety of traditional and natural sources including cow’s milk. He consistently found that these people enjoy immunity to many of today’s most common diseases including heart disease.

There’s clearly a significant inconsistency between conventional dietary beliefs and the evidence provided to us by nature. Which is more trustworthy?

A Closer Look at Fat

The many important benefits of saturated fat include stable cell membranes and healthy brain, lung, and skin function. It can also boost immunity and is also an important source of energy and fat soluble vitamins. Another advantageous characteristic of saturated fat is that it’s very stable.1

To decrease the production cost of processed foods and increase their shelf life, the food industry uses a process called hydrogenation to turn oils containing unstable polyunsaturated fats into a substance that is more stable and more similar to saturated fat. However, the unstable polyunsaturated fatty acids in the oil are easily oxidized during this process which results in free radicals that may cause cellular damage and increase the risk of heart disease and other major health problems.8-15 In addition, the substance resulting from hydrogenation, commonly referred to as trans fat, is similar enough in structure to saturated fat to be used by the body, but different enough to cause significant problems.2 Although natural saturated fat has been labeled as the dietary villain, trans fat is a much more likely cause of heart disease as well as many other problems.

According to conventional wisdom, the risk of heart disease is reduced by choosing skim or low fat milk instead of whole milk and using polyunsaturated vegetable oils instead of saturated fat. However, more and more evidence is indicating that this belief is not only wrong, but completely backwards.23-35

The Ironic Risks of Drinking Low Fat Milk

It’s standard practice for dairy producers to improve the protein content of skim milk and low fat milk by adding dried milk powder to it. This dried milk is produced by forcing skim milk through tiny holes at high temperatures and pressures which damages its nutrients. This also causes the milk’s cholesterol to become oxidized which is a legitimate risk for heart disease.2-4,16-22 Ironically, the milk’s natural and nutritious saturated fat is removed because it’s supposedly unhealthy, but then a more likely promoter of heart disease is added. Although the amount of oxidized cholesterol in skim milk and reduced fat milk may be small, there’s really not much point in taking the risk.

Another potential problem with consuming skim milk or low fat milk is vitamin A deficiency. Because vitamin A is a fat soluble vitamin, its concentration in milk is reduced through the removal of fat. As a result, when skim milk or low fat milk is consumed and digested, the vitamin A needed for the assimilation of its protein is drawn from the liver. This can deplete the body’s reserve of vitamin A, and in turn, increase the risk of autoimmune disease and cancer.5

The Politics of Low Fat Milk

We’re consistently told by the USDA and dietitians that skim milk and low fat milk are the healthiest choices, and probably not by coincidence, this is exactly what the dairy industry wants us to believe. This is because the cream that’s extracted from whole milk to reduce its fat content can be used for other dairy products and therefore generate more profit from the same quantity of milk.

According to the Center for Responsive Politics, the dairy industry donated nearly $5 million to political campaigns6 and spent nearly another $5 million on lobbying7. Based on this, the dairy industry is clearly interested in keeping politicians on their side, and their contributions are very likely to be a significant factor behind the mainstream belief that it’s healthier to drink skim milk and low fat milk.

Homogenization is Another Cause for Concern

Homogenization changes the nutritional quality of milk by altering the structure of its fat molecules. During homogenization, milk is forced at high pressure and temperature through tiny holes to break its fat molecules into smaller globules. This results in fat molecules with a much higher than normal membrane concentration of casein and whey proteins which has the potential to increase their allergenic properties. In addition, beneficial components have been found in the membrane of the fat molecules in milk that help suppress pathogenic organisms and protect against multiple sclerosis, Alzehimer’s disease, depression, and stress, but homogenization eliminates these benefits.5

Most of the milk available in grocery stores is both pasteurized and homogenized. Even though pasteurization reduces the quality of milk and promotes the use of poor dairy farming practices, it at least serves an arguably important purpose. It destroys many of the pathogens that can contaminate milk and cause infection. In contrast, the only benefit of homogenization is that it prevents the cream in milk from separating and rising to the top by keeping its fat molecules evenly dispersed. This is nothing more than a matter of convenience and aesthetics, neither of which justify the alteration of a food’s nutrients.

More About Milk

For more information about the history, politics, and health benefits of milk, including the controversies surrounding pasteurization, I highly recommend reading The Untold Story of Milk by Ron Schmid ND. For more information on the chemistry and health benefits of fat, I recommend reading Know Your Fats by Mary Enig PhD.

Another important issue to consider is the potentially dangerous A1 beta casein that exists in the milk produced by certain breeds of cattle. You can find more information on the risks associated with A1 beta casein in Devil in the Milk by Keith Woodford.

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