The Evidence for Saturated Fat and for Sugar Related to Coronary Heart Disease

Abstract

Dietary guidelines continue to recommend restricting intake of saturated fats. This recommendation follows largely from the observation that saturated fats can raise levels of total serum cholesterol (TC), thereby putatively increasing the risk of atherosclerotic coronary heart disease (CHD). However, TC is only modestly associated with CHD, and more important than the total level of cholesterol in the blood may be the number and size of low-density lipoprotein (LDL) particles that contain it. As for saturated fats, these fats are a diverse class of compounds; different fats may have different effects on LDL and on broader CHD risk based on the specific saturated fatty acids (SFAs) they contain. Importantly, though, people eat foods, not isolated fatty acids. Some food sources of SFAs may pose no risk for CHD or possibly even be protective. Thus, advice to reduce saturated fat in the diet without regard to such nuance could actually increase people’s risk of CHD. When saturated fats are replaced with refined carbohydrates, and specifically with added sugars (like sucrose or high fructose corn syrup), the end result is not favorable for heart health. Such replacement leads to changes in LDL, high-density lipoprotein (HDL), and triglycerides that may increase the risk of CHD. Additionally, diets high in sugar may induce many other abnormalities associated with elevated CHD risk, including elevated levels of glucose, insulin, and uric acid, impaired glucose tolerance, insulin and leptin resistance, non-alcoholic fatty liver disease, and altered platelet function. A diet high in added sugars has been found to cause a 3-fold increased risk of death due to cardiovascular disease. But sugars, like saturated fats, are a diverse class of compounds. The monosaccharide, fructose, and fructose-containing sweeteners (e.g., sucrose) result in greater degrees of metabolic abnormalities than seen with glucose (either isolated as a monomer or in chains as starch) and may present greater risk for CHD. This paper reviews the evidence linking saturated fats and sugars to CHD, and concludes that the latter is more of a problem than the former. Dietary guidelines should shift focus away from reducing saturated fat, and from replacing saturated fat with carbohydrates, specifically when these carbohydrates are refined. To reduce the burden of CHD, guidelines should focus particularly on reducing intake of concentrated sugars, specifically the fructose-containing sugars like sucrose and high-fructose corn syrup in the form of ultra-processed foods and beverages.

Global Correlates of Cardiovascular Risk: A Comparison of 158 Countries

“…Meta-analyses of observational studies and available clinical trials have not been able to find any reliable link between saturated fat and CVDs [1][2][3][4][5][6][7] which has been the pillar of official nutritional guidelines for more than three decades. A decrease of CVD prevalence/mortality occurs only when saturated fat is replaced by polyunsaturated fat (PUFAs) which is more likely to be related to the beneficial effects of PUFAs on blood lipid profiles, rather than to any harmful role of saturated fat.…”

“…Furthermore, even this conclusion was recently questioned and attributed to methodological flaws [8]. On the other hand, we are witnessing growing evidence of the fundamental role of carbohydrates and high glycaemic index/load in the aetiology of CVDs [1][2][9][10][11][12].…”

Sugar, Cavities, Systemic Disease and Addiction?

“…sucrose) produce greater degrees of metabolic abnormalities than does glucose (either isolated as a monomer, or in chains as starch) and may present greater risk of CHD. To reduce the burden of CHD, guidelines should focus particularly on reducing intake of concentrated sugars, specifically the fructose-containing sugars like sucrose and high-fructose corn syrup in the form of ultra-processed foods and beverages [19] Others have found that consumption of added sugar is associated with development and/or prevalence of fatty liver, dyslipidemia, insulin resistance, hyperuricemia, CVD and type 2 diabetes and failure to stimulate leptin production [20][21][22][23].…”

Study on the effects of varying concentrations of xylitol on the weight, and blood glucose, and cholesterol levels of Mus musculus L. (ICR mice)

“…[5] Taking in too much sugar would result to the storing of excess sugar as triglycerides and synthesis of cholesterol. [6] High concentrations of triglycerides raise the low-density lipoproteins (LDL) high-density lipoprotein (HDL), which causes the deposit of cholesterol to the arterial walls. This also lowers the HDL concentration, which counteracts the LDL.…”

“…[7] Other effects of excess intake of sugar include obesity, diabetes, and heart diseases. [6] With these diseases becoming apparent, many sugar substitutes, such as sucralose, stevia, aspartame, sugar alcohols, and many more, have emerged. These substitutes claim to be better as these have lesser calories compared to regular sugar and that they neither increase nor decrease blood sugar levels significantly.…”