By Lisa Egan
It seems obvious: eating fat makes you fat and unhealthy, right?
Well, not quite. As with most things related to nutrition and health, it isn’t that simple or straightforward. A combination of flawed studies, political bias, and clever marketing by the food industry led to the birth of the low-fat craze – a trend that has lasted nearly 40-years. Thankfully, that craze finally appears to be in its death throes.
The idea that dietary fat was bad for health didn’t start until around 1940, when some scientists and physicians started to suspect that diets high in saturated fats and cholesterol were linked to heart disease. This was based on their interpretation of some research, which was not without controversy – some experts were skeptical and didn’t jump on the “fat is bad” bandwagon.
By the 1950s, doctors were recommending low-fat diets to patients who were considered at risk for cardiovascular disease.
Even though some studies did not support what came to be known as the “diet-heart hypothesis”, and there was no proof of a link between dietary fat and cardiovascular disease, the ideology picked up speed.
And the low-fat craze slowly began.
But the ideology wasn’t pushed upon the public at large until 1977 – that’s when the U.S. Senate’s Select Committee on Nutrition and Human Needs, chaired by George McGovern, published its report titled Dietary Goals for the United States. That report encouraged people to switch to nonfat milk and limit the consumption of butter and eggs. Some scientists remained skeptical of these suggestions, but the advice spread like wildfire anyway.
By 1980, the idea that a low-fat diet could help reduce risk of heart disease and cancer was generally accepted within the scientific community. The World Health Organization and the Surgeon General promoted the diet.
It didn’t take long before the food industry saw the profit-making potential of low-fat products. Seemingly overnight, supermarket shelves were filled with low-fat and non-fat cookies, crackers, cheese, and ice cream – if there was a way to make a food item have less fat, companies did it.
Several years into the low-fat craze, some researchers started to realize that the trend wasn’t such a good thing after all:
While the low-fat diet reigned supreme in the 1990s, more scientific dissenters came forward. Dr. Jules Hirsch, a leading obesity researcher at Rockefeller University, found that when the fat content of a diet was less than 20 percent, the body begins to synthesize saturated fat from carbohydrates. Dr. Walter Willett at the Harvard School of Public Health identified that substituting carbohydrates for fats reduced HDL cholesterol and increased triglycerides, both of which increase risk of developing heart disease.
Through the 1990s and into the 2000s, the growing popularity of high-fat diets, such as Atkins or the Mediterranean diets, led to the realization that eating fat does not necessarily make a person fat. (source)
From the American Journal of Clinical Nutrition:
Although intake of saturated fat should remain at a relatively low amount and partially hydrogenated fats should be eliminated, a singular focus on reduction of total and saturated fat can be counterproductive because dietary fat is typically replaced by refined carbohydrate, as has been seen over the past several decades. In this era of widespread obesity and insulin resistance, the time has come to shift the focus of the diet-heart paradigm away from restricted fat intake and toward reduced consumption of refined carbohydrates.
In other words, the low-fat diet has not proven to be effective at reducing heart disease or our waistlines, and the resulting increase in refined carbohydrates hasn’t done us any good, either.
In fact, several recent studies have shown that dietary fat (even saturated fat) and cholesterol are actually associated with LESS obesity. Let’s look at the results of two of those studies.
In one paper, published by Swedish researchers in the Scandinavian Journal of Primary Health Care, middle-aged men who consumed high-fat milk, butter and cream were significantly less likely to become obese over a period of 12 years compared with men who never or rarely ate high-fat dairy.
The second study, published in the European Journal of Nutrition, is a meta-analysis of 16 observational studies. There has been a hypothesis that high-fat dairy foods contribute to obesity and heart disease risk, but the reviewers concluded that the evidence does not support this hypothesis. In fact, the reviewers found that in most of the studies, high-fat dairy was associated with a lower risk of obesity.
So, to our original question: which is more healthful – low-fat or full-fat dairy products?
We have already established that the fat in whole dairy products does not lead to weight gain.
But what about other impacts on health?
Here are some other reasons to choose full-fat dairy products over non-fat or low-fat options:
- Increased satiety: full-fat versions are more filling
- Less sugar: low-fat and non-fat dairy products often have sugar added to enhance flavor
- Beneficial fatty acids: whole milk contains more omega-3 fatty acids than lower fat versions – this is especially true for organic milk, which contains higher levels than conventional milk
- Improved vitamin absorption: milk contains the fat-soluble vitamins A, D, E, and K – and whole milk contains fat, which helps your body absorb those vitamins
- Less abdominal obesity: Studies show that a high intake of dairy fat is associated with a lower risk of central obesity and a low dairy fat intake is associated with a higher risk of central obesity (which can increase heart disease risk)
- Less processing and additives: fat-free and low-fat products often have thickeners and chemicals added to them to enhance flavor and texture – whole milk does not
Speaking of dairy products, real butter offers health benefits as well. It contains fat soluble vitamins including A, E, and K2, which is involved in calcium metabolism. Low intake of K2 has been associated with many serious diseases, including cardiovascular disease, cancer and osteoporosis. Dairy from grass-fed cows is particularly high in this vitamin.
Butter also contains saturated fats, which raise good cholesterol. It also contains a 4-carbon fatty acid called butyrate, which has anti-inflammatory properties and offers protection to the digestive system. Butter is a great source of Conjugated Linoleic Acid (CLA), which is a fatty acid that has been shown to have anti-cancer properties in some studies.
And, butter contains a very unique substance called the Wulzen factor, a hormone-like substance that prevents arthritis and joint stiffness. It ensures that calcium in the body is put into the bones rather than the joints and other tissues. The Wulzen factor is present only in raw butter and cream; it is destroyed by pasteurization.
Side note: Eggs, while not a dairy food, deserve a mention here, as they have long been demonized for their high fat and cholesterol content. Discarding the yolks is common practice, which is unfortunate, because that part of the egg is abundant in nutrients. In addition, the cholesterol in egg yolks does not have any affect on cholesterol levels in the body.
Back to dairy products – milk from grass-fed cows is generally of better quality and usually can be consumed without being pasteurized. If you choose to consume pasteurized milk, choose organic if possible. Milk from a local organic dairy farm is ideal, and if raw milk is offered, that is even better.