Though largely driven by misinterpretation of the science and cherry-picked population studies, the “Butter is Back” movement comes with very persuasive sound bites followed by arrogant punctuation marks. No wonder so many people hopped on board the bandwagon while looking back, pointing fingers and shouting “health professionals have been misleading us for decades!” Yet the flawed reasoning behind the pro-saturated fat movement comes with a hefty price tag – you could be making food choices that, over time, will increase your risk for cardiovascular disease and type 2 diabetes.
Here’s what I’ll cover in this article:
- Why is there so much confusion about saturated fat?;
- The science behind saturated fats, cardiovascular disease (diseases of the heart & blood vessels) and type 2 diabetes;
- Best food choices for heart health.
Why is there so Much Confusion about Saturated Fat?
There are a few reasons for the confusion about saturated fat (fat that is solid at room temperature such as butter, shortening, coconut oil and the fat on meat) and misinterpretation of the science. First off, some people group all saturated fatty acids (saturated fatty acids make up saturated fat) together as a team. However, there are several types of saturated fatty acids. Some raise LDL cholesterol (the kind that contributes to clogged arteries and is a risk factor for cardiovascular disease) as well as HDL cholesterol (“good” cholesterol, the kind that removes bad cholesterol; SN: drugs that increase HDL do not lower risk of heart disease so there is some considerable debate regarding the role of HDL), others don’t raise LDL cholesterol and some we aren’t quite sure about. Secondly, using population-based studies alone to draw conclusions about saturated fat intake and heart disease is misguided. These studies are not designed to determine cause and effect (that’s the job of well-designed clinical trials) plus, there are inherent issues with the methods used in many of these studies. Nutrition research is not easy, especially in humans living their life (those not in a metabolic ward where all factors are controlled and measured including diet and physical activity).
Lastly, some research studies (and the media) take the results way out of context. So, here’s the lowdown based on sound science:
The Science Behind Saturated Fat, Cardiovascular Disease and Type 2 Diabetes
- There is no dietary requirement for saturated fat. Your body can make all of the saturated fatty acids it needs.
- Foods high in saturated fat typically increase total, HDL and LDL cholesterol. However, the impact dietary saturated fat has on increasing LDL-cholesterol (the kind that contributes to clogged arteries and an inflammatory cascade in arteries) may depend on the amount of polyunsaturated fat (PUFAs) in your diet (as well as the type of saturated fatty acids consumed).
- In general, replacing saturated fat with polyunsaturated fat (and monounsaturated fat though there is less evidence for monounsaturated fat) reduces LDL and total cholesterol, both risk factors for cardiovascular disease.
- Overweight, obesity and insulin resistance may reduce the beneficial effects (lowered LDL cholesterol) generally noticed from a reduction in saturated fat intake. *If obese or overweight, losing excess body fat (regardless of the type of diet used to lose the weight) has powerful effects on lowering risk for cardiovascular disease, some cancers, and type II diabetes.
- Food contains a complex mixture of compounds that may affect cholesterol and cardiovascular disease risk (it is not just the fat). The food “matrix” matters.
- Many factors impact how a food affects cholesterol and blood lipids (fats) including fats eaten at the same time, overall diet, and carbohydrate intake (and type of carbohydrates consumed – high fiber vs. foods high in added sugar with few other nutrients).
- There are individual, genetic differences in response to saturated fat intake – your cholesterol might shoot up after eating a diet containing a diet high in the type of saturated fatty acids that raise LDL cholesterol and I might be able to get away with this diet without a problem (blame your genetics or consider it an opportunity to open your taste buds to foods containing less saturated fat; particularly the kind that is artery clogging).
- Certain saturated fatty acids, or a diet high in saturated fat, may increase risk for type 2 diabetes.
Best Choices for Heart Health
If you are overweight, focus on losing excess body fat. Even small amounts of fat loss will improve health and risk factors for cardiovascular disease. If you have high total and LDL cholesterol, swap foods high in saturated fat for foods high in polyunsaturated fat (liquid oils, nuts, seeds, olives, avocados). Minimize your intake of foods high in added sugars and refined, white flour, carbohydrates. Instead, choose higher fiber carbohydrates as often as possible.
Don’t get sucked into the media headlines written by journalists who could sell ice to an eskimo. Butter isn’t back (for good health anyway). The bulk of your fat intake should still come from foods that are higher in polyunsaturated and monounsaturated fats. However, food is a complex matrix of compounds and therefore, some foods higher in saturated fat may have little to no impact on cholesterol and therefore fit into your diet while contributing to your vitamin and mineral needs and providing plant-based compounds important for good health.
Tholstrup T, Hoy CE, Andersen LN, Christensen RD, Sandstrom B. Does fat in milk, butter and cheese affect blood lipids and cholesterol differently? J Am Coll Nutr 2004;23:169–76.
Nestel P. Effects of Dairy Fats within Different Foods on Plasma Lipids. J Am Coll Clin Nutr 2008, 27(6): 735S–740S.
Hodson L, Skeaff CM, Chisholm WA. The effect of replacing dietary saturated fat with polyunsaturated or monounsaturated fat on plasma lipids in free-living young adults. Eur J Clin Nutr 2001; 55(10):908-15
Soerensen KV et al. Effect of dairy calcium from cheese and milk on fecal fat excretion, blood lipids, and appetite in young men. Am J Clin Nutr 2014;99(5):984-91.