A recent Washington Post article by Peter Whoriskey offers a comprehensive look at the research and history behind why people think food sources rich in saturated fats, whole milk specifically, should be avoided. Whoriskey concludes that saturated fats do not in fact contribute to heart disease—a notion that goes against decades of conventional wisdom. There is a bit more at play here than a surface reading suggests, however, and a proper understanding of what these findings mean requires some explanation.
At the center of the case against saturated fats is a simple set of logic: saturated fats raise the levels of low-density lipoprotein (LDL) cholesterol—the “bad” cholesterol—and can cause heart disease. Therefore, cutting out saturated fats will reduce LDL levels. The problem here is that this model looks at the matter from a purely macro-level; meaning it uses blanket terms like “cholesterol,” “protein,” “fat,” and so on. Going further, to the level the body actually operates on, makes things far more uncertain than initially believed.
All Saturated Fats Are Not Created Equal
In simple terms, saturated fat is a bundle of fatty acids that are saturated with hydrogen atoms. While there are some commonalities between different saturated fats, the more important part is that there are differences. The saturated fat you get from a glass of whole milk is not the same kind that you would get from a plate of sausages. Secondly, the amount of saturated fat in a food does not tell the entire story. Each kind of fatty acid is a chain of carbon with differing lengths that are handled by the body in different ways. Some fatty acids are capable of raising the levels of LDL cholesterol in your body while others don’t appear to have an impact on levels in either direction.
In short, getting the same amount of saturated fat from two different sources does not necessarily mean your body will experience the same effects from it.
Some Types of LDL Cholesterol Won’t Affect Risk of Heart Disease
LDL cholesterol is understood to be the bad type. It is capable of infiltrating the lining of the arteries and building up as plaques. However, there are multiple types of LDL cholesterol based on how dense the components are bound. The largest type of LDL, typically referred to as “fluffy,” does not appear to have much effect on heart disease or at the very least has a much smaller role compared to its fellows. The increasingly denser types, called medium, small, and very small, are the ones that cause problems and can lead to plaques.
While there are tests that can distinguish between the different types of LDL cholesterol, most of the typical assessments can’t. A person with a high cholesterol level may have an abundance of the large type but not know it.
What This Means for Your Diet
Strictly speaking, this information may not require any change in your diet. Most of the science still supports the idea that swapping out saturated fats for unsaturated ones (but not carbs) can reduce your risk of heart disease. The benefit, however, is more likely to be from the increase of unsaturated fats rather than the decrease of saturated ones.
It’s also important to remember that although the studies linking saturated fat to heart disease aren’t as unshakable as once believed, their results still exist. Just as studies have found that saturated fats don’t have a link to heart disease, some have found the exact opposite. One even found that saturated fats caused an increase in heart disease but not in deaths from heart disease. At best, all of these studies combine to say that “saturated fats may not all be bad,” rather than “some saturated fats are actually good.”
The best lesson to take away from all this is to look at food as a whole rather than as to whether or not it has saturated fat. For instance, whole milk and the dairy products derived from it can all increase your LDL cholesterol. However, this cholesterol is largely the “fluffy” kind. It also raises high-density lipoprotein (HDL) cholesterol levels (the good type), which further helps even things out. When combined with the other nutrients milk contains, it may not be a bad option. However, this is only when looking at things from a pure cardiovascular perspective. Whole milk, after all, still has more calories than skim milk, which may still make it undesirable for some.
The Bottom Line
All of this can be boiled down to a few main points:
- Saturated fats are not created equal. A food or beverage product that has saturated fat does not automatically make it bad for your heart.
- Some types of LDL cholesterol won’t affect your risk of coronary heart disease, but traditional testing does not reflect this.
• Saturated fats from dairy products are probably fine for your heart, but just be careful of what else might be in the food you eat. You should still avoid that deep-fried stick of butter.
Replacing saturated with unsaturated fats can reduce your risk of heart disease.
Sources for Today’s Article:
“Cholesterol and Artery Plaque Buildup,” WebMD web site; http://www.webmd.com/cholesterol-management/cholesterol-and-artery-plaque-buildup, last accessed October 8, 2015.
Chowdhury, R., et al., “Association of Dietary, Circulating, and Supplement Fatty Acids With Coronary Risk,” Annals of Internal Medicine 2014; 160(6): 398-406.
Hooper, L., et al., “Reduced or Modified Dietary Fat for Preventing Cardiovascular Disease,” Cochrane Database of Systematic Reviews 2011; 7; doi:10.1002/14651858.CD002137.pub2.
Malhotra, A., “Saturated Fat Is Not the Major Issue,” British Medical Journal 2013; 347; doi:http://dx.doi.org/10.1136/bmj.f634.
Patruel, A., “Is Butter Back? The Truth About Saturated Fats,” WebMD web site; http://www.webmd.com/cholesterol-management/features/truth-about-saturated-fats, last accessed October 8, 2015.
Scott, P., “Bad Cholesterol: It’s Not What You Think,” NBCNews.com, last updated February 14, 2010; http://www.nbcnews.com/id/35058896/ns/health-heart_health/t/bad-cholesterol-its-not-what-you-think/#.VhanrPlVikp, last accessed October 8, 2015.
Whoriskey, P., “For Decades, the Government Steered Millions Away from Whole Milk. Was That Wrong?” Washington Post web site, October 6, 2015; http://www.washingtonpost.com/news/wonkblog/wp/2015/10/06/for-decades-the-government-steered-millions-away-from-whole-milk-was-that-wrong/?postshare=2031444179793533.