As human beings, we love to categorize things, including our food. We tend to demonize one nutrient while putting a halo over another. A great example of this is saturated fat. It used to be the bad guy but now the pendulum has swung the other way and we are seeing statements such as this enticing advice from a June 2016 TIME article: “It looks like butter may, in fact, be back.” So what’s the deal?
The Different Kinds of Fat
First, a little food science lesson for you. Fats can be classified as either saturated or unsaturated. These terms are used to describe the chemical structure of the fatty acid compound. The term “saturated” is used when the carbon chain of the fatty acid is filled with hydrogen atoms (in other words, it is “saturated” with hydrogen). The term “unsaturated” is used when one or more of the hydrogen atoms are missing from the carbon chain. The result of these different compositions is that saturated fats are generally solid at room temperature (think of butter) and unsaturated fats are in a liquid state (think olive oil).
Some examples of foods that contain a lot of saturated fat are butter and other full-fat dairy products such as milk, cheese, and yogurt.
Why does this matter? Historically, a large body of research has shown that saturated fat raises LDL cholesterol (the “bad” kind), which has a well-established link to increased risk of cardiovascular disease. This led to the advice to consume low-fat or no-fat dairy products and to avoid butter. But some recent research has called this advice into question.
Several studies in the past few years have challenged the old advice that certain sources of saturated fat, such as full-fat dairy, should be avoided. For example, the meta-analysis from Dr. Dariush Mozaffarian of Tufts University that inspired the TIME article mentioned above, found that butter had a “neutral” effect on cardiovascular disease risk, and was modestly protective for type 2 diabetes risk. These relatively minor findings do not make for sexy headlines, so the media tends to ramp up the pizzazz with statements such as the one from TIME. What is important to understand about Mozaffarian’s research, is that butter was compared to all other foods in the diet, including soda, sugar, refined grains, and hydrogenated vegetable oils – all foods that have a well-established link to chronic disease risk. The study did not make a one-to-one comparison of butter to an unsaturated fat such as olive oil. To encourage increased consumption of butter or tout it as a health food is unwarranted. This article from Harvard gives a straight-forward interpretation of the study’s findings.
Even the nutrition experts have been confused by this controversial issue. At the Academy of Nutrition and Dietetic’s annual conference in October 2016, I had the pleasure of attending a session titled, “Going Coconut Over Saturated Fat? Why So Much Confusion?” presented by Alice Lichtenstein, D.Sc. and Carol Kirkpatrick, PhD, RDN.
These experts gave a nice overview of the problem that has created the confusion over saturated fat. Starting in the 70’s, when research pointed to the connection of saturated fat with increased cardiovascular disease risk, the second part of the message got lost somehow: saturated fats should be replaced with unsaturated fats. Unfortunately, only the first part of the picture was portrayed to the public, and the message of limiting saturated fat morphed into limiting total fat, as is seen in the 1980’s Dietary Guidelines for Americans statement, “Avoid too much fat, saturated fat, and cholesterol.”
This advice led to Americans cutting all kinds of fat from their diets. But human nature predicts that calories cut from one nutrient will be replaced by another, and that led to an increased intake of processed carbohydrates. An entire category of processed food was born: fat free desserts. While fat free cookies don’t contain fat, guess what they contain plenty of? Refined sugar. And with a label of “fat free,” this mistakenly gave people the green light to indulge and overeat these kinds of products because of the perceived “health halo.” Loading up on refined grains, sugars, and starches increases risk for weight gain and chronic diseases, such as type 2 diabetes.
What Really Matters?
The two things that matter when it comes to advice on saturated fat are: 1) what we replace it with, and 2) our dietary pattern as a whole. It is still sound advice to be conservative with foods that contain saturated fat (such as lard, coconut oil, palm oil, and butter) but equally important is to replace those kinds of fats with healthy unsaturated fats (olive oil, canola oil, soybean oil, and flaxseed oil). Do not replace saturated fat with refined grains, sugars, and starches.
Finally, the totality of your eating is more important than getting stuck in the nitty-gritty details of nutrients like saturated fat. Focus on including whole foods, such as fruits and vegetables, whole grains, vegetable oils, lean meat, seafood, legumes, soy, nuts and seeds. And yes, quality full fat dairy and butter have a place in a healthy diet full of variety. Often, a smaller serving of the real-deal will leave you feeling satisfied, whereas a “pretend” product (think fat-free cookies) will leave you chasing the taste you crave by overeating. In my fridge, you’ll find half and half for my coffee, butter for my whole grain toast, and real ice cream in the freezer. I don’t want to compromise on taste and satisfaction, and I integrate these foods into a healthful eating pattern.