The effects of saturated fat on health is among the most controversial topics in all nutrition. While some experts warn that consuming too much — or even moderate amounts — can negatively affect health, others argue that saturated fats aren’t inherently harmful and can be included as part of a healthy diet ( 1 ). This article explains what saturated fat is and takes a deep dive into the latest findings in nutrition research to shed light on this important and often misunderstood topic. Share on Pinterest

What is saturated fat and why has it gotten a bad rap? Fats are compounds that play essential roles in many aspects of human health. There are three main categories of fats: saturated fats, unsaturated fats, and trans fats. All fats are made up of carbon, hydrogen, and oxygen molecules ( 2 ). Saturated fats are saturated with hydrogen molecules and contain only single bonds between carbon molecules. On the other hand, unsaturated fats have at least one double bond between carbon molecules. This saturation of hydrogen molecules results in saturated fats being solid at room temperature, unlike unsaturated fats, such as olive oil, which tend to be liquid at room temperature. Keep in mind that there are different types of saturated fats depending on their carbon chain length, including short-, long-, medium-, and very-long-chain fatty acids — all of which have different effects on health. Saturated fats are found in animal products like milk, cheese, and meat, as well as tropical oils, including coconut and palm oil ( 3 ). Saturated fats are often listed as “bad” fats and are commonly grouped with trans fats — a type of fat that’s known to cause health issues — even though evidence on the health effects of saturated fat intake is far from conclusive. For decades, health organizations around the world have recommended keeping saturated fat intake to a minimum and replacing it with highly processed vegetable oils, such as canola oil, to decrease heart disease risk and promote overall health. Despite these recommendations, heart disease rates — which have been linked to saturated fat intake — have steadily risen, as have obesity and related diseases, such as type 2 diabetes, which some experts blame on overreliance on carb-rich, processed foods ( 1 , 4 ). Plus, a number of studies, including large reviews, contradict the recommendations to avoid saturated fat and instead consume vegetable oils and carb-rich foods, leading to warranted consumer confusion ( 5 , 6 , 7 ). Additionally, many experts argue that one macronutrient can’t be blamed for disease progression and that diet as a whole is what matters. summary Saturated fats are found in animal products and tropical oils. Whether or not these fats increase disease risk is a controversial topic, with study results supporting both sides of the argument.

The effect of saturated fat on heart health One of the main reasons for recommending that saturated fat intake be kept to a minimum is the fact that saturated fat consumption may increase certain heart disease risk factors, including LDL (bad) cholesterol. However, this subject isn’t black and white, and although it’s clear that saturated fat commonly increases certain heart disease risk factors, there’s no conclusive evidence that saturated fat increases heart disease risk. Saturated fat intake may increase heart disease risk factors, but not heart disease itself Numerous studies have shown that saturated fat intake increases heart disease risk factors, including LDL (bad) cholesterol and apolipoprotein B (apoB). LDL transports cholesterol in the body. The greater the number of LDL particles, the greater the risk of heart disease. ApoB is a protein and a main component of LDL. It’s considered a strong predictor of heart disease risk ( 8 ). Saturated fat intake has been shown to increase both of these risk factors, as well as the LDL (bad) to HDL (good) ratio, which is another heart disease risk factor ( 9 , 10 ). HDL is heart protective, and having low levels of this beneficial cholesterol is associated with an increased risk of heart disease and cardiovascular complications ( 11 , 12 ). However, although well-designed studies have shown a relationship between saturated fat intake and heart disease risk factors, research has failed to discover a significant link between saturated fat consumption and heart disease itself. Plus, current research doesn’t show a significant association between saturated fat intake and all-cause mortality or stroke ( 13 , 14 , 15 , 16 , 17 , 18 ). For example, a 2014 review of 32 studies that included 659,298 people found no significant association between saturated fat intake and heart disease ( 18 ). A 2017 study that followed 135,335 individuals from 18 countries for an average of 7.4 years demonstrated that saturated fat intake wasn’t associated with stroke, heart disease, heart attack, or heart-disease related death ( 17 ). What’s more, findings from randomized controlled studies show that the general recommendation to replace saturated fats with omega-6-rich polyunsaturated fats is unlikely to decrease the risk of heart disease and may even increase disease progression ( 19 , 20 ). However, there have been conflicting findings, which can be attributed to the highly complex nature of this topic and the design and methodological flaws of currently available research, highlighting the need for future well-designed studies investigating this topic ( 6 ). Plus, it’s important to remember that there are many types of saturated fat, each with its own effects on health. Most of the studies investigating the effects of saturated fat on disease risk discuss saturated fats in general, which is also problematic. Other concerns over saturated fat intake Although its effect on heart disease is by far the most researched and contested, saturated fat has also been associated with other negative health effects, such as increased inflammation and mental decline. For example, a study in 12 women found that, when compared with a diet high in unsaturated fat from hazelnut oil, a diet high in saturated fat from a blend of 89% palm oil increased the pro-inflammatory proteins interleukin-1 beta (IL-1 beta) and interleukin-6 (IL-6) ( 21 ). Some evidence suggests that saturated fats encourage inflammation partly by mimicking the actions of bacterial toxins called lipopolysaccharides, which have strong immunostimulant behaviors and can induce inflammation ( 22 ). However, research in this area is far from conclusive, with some studies, including a 2017 review of randomized controlled trials, finding no significant associations between saturated fat and inflammation ( 23 ). Additionally, some studies have demonstrated that saturated fat may have adverse effects on mental function, appetite, and metabolism. Yet, human research in these areas is limited and findings are inconsistent ( 24 , 25 , 26 ). More studies are necessary to investigate these potential links before strong conclusions can be made. summary Though saturated fat intake may increase heart disease risk factors, research hasn’t shown a significant link between it and heart disease itself. Some studies indicate that it may negatively affect other health aspects, but more research is needed.

Is saturated fat unhealthy? Although research indicates that consuming some types of food high in saturated fat may adversely affect health, this information can’t be generalized to all foods that contain saturated fat. For example, a diet high in saturated fats in the form of fast food, fried products, sugary baked goods, and processed meats is likely to affect health differently than a diet high in saturated fats in the form of full fat dairy, grass-fed meat, and coconut. Another problem lies in focusing solely on macronutrients and not the diet as a whole. Whether or not saturated fat increases disease risk likely depends on what foods it’s being replaced with — or what it’s replacing — and overall diet quality. In other words, individual nutrients aren’t to blame for disease progression. Humans don’t consume just fat or just carbs. Rather, these macronutrients are combined through consuming foods that contain a mixture of macronutrients. What’s more, focusing exclusively on individual macronutrients rather than the diet as a whole doesn’t take into consideration the effects of dietary constituents, such as added sugars, that may negatively affect health. Lifestyle and genetic variants are important risk factors that should be considered as well, as both have been proven to affect overall health, dietary needs, and disease risk. Clearly, the effect of diet as a whole is difficult to research. For these reasons, it’s clear that larger, well-designed studies are necessary to separate associations from facts. Summary Individual macronutrients aren’t to blame for disease progression. Rather, it’s the diet as a whole that truly matters.

Saturated fat as part of a healthy diet There’s no question that foods high in saturated fat can be enjoyed as part of a healthy diet. Coconut products, including unsweetened coconut flakes and coconut oil, grass-fed whole milk yogurt, and grass-fed meat are just some examples of highly nutritious foods concentrated in saturated fat that may positively affect health. For example, reviews of research have shown that full fat dairy intake has a neutral or protective effect on heart disease risk, while coconut oil intake has been shown to boost HDL (good) cholesterol and may benefit weight loss ( 27 , 28 ). On the other hand, consuming processed foods rich in saturated fats, including fast food and fried foods, has been consistently linked to an increased risk of obesity, heart disease, and numerous other health conditions ( 29 , 30 ). Research has also associated dietary patterns rich in unprocessed foods with protection from various conditions, including obesity and heart disease, and reduction of disease risk factors, regardless of dietary macronutrient composition ( 31 , 32 , 33 , 34 , 35 , 36 , 37 ). What has been established through decades of research is that a healthy, disease-protective diet should be rich in nutritious, whole foods, especially high fiber plant foods, though it’s clear that nutritious foods high in saturated fat can be included as well. Remember, regardless of what dietary pattern you choose, the most important thing is balance and optimization — not omission.

Summary A healthy diet should be rich in whole, nutritious foods, regardless of macronutrient composition. Saturated fats can be included as part of a healthy diet.