Intrahepatic Fat and Postprandial Glycemia Increase After Consumption of a Diet Enriched in Saturated Fat Compared With Free Sugars

• Published in: Diabetes care Vol. 43; no. 5; pp. 1134 - 1141
• Main Authors: Parry, Siôn A, Rosqvist, Fredrik, Mozes, Ferenc E, Cornfield, Thomas, Hutchinson, Matthew, Piche, Marie-Eve, Hülsmeier, Andreas J, Hornemann, Thorsten, Dyson, Pamela, Hodson, Leanne
• Format: Journal Article
• Language: English
• Published: United States American Diabetes Association 01-05-2020
• Subjects: Adult; Blood glucose; Blood Glucose - drug effects; Blood Glucose - metabolism; Body fat; Body weight; Cardiovascular and Metabolic Risk; Cholesterol; Consumption; Cross-Over Studies; Diet; Diet, High-Fat - adverse effects; Dietary Carbohydrates - pharmacology; Dietary Fats - pharmacology; Enrichment; Fats; Fatty Acids - metabolism; Fatty Acids - pharmacology; Fatty liver; Health risks; High density lipoprotein; Humans; Imaging techniques; Insulin; Insulin Resistance; Lipid Metabolism - drug effects; Lipids - blood; Lipogenesis; Lipolysis; Liver - drug effects; Liver - metabolism; Liver diseases; Male; Males; Meals; Metabolic disorders; Metabolism; Middle Aged; Non-alcoholic Fatty Liver Disease - etiology; Non-alcoholic Fatty Liver Disease - metabolism; Oxidation; Postprandial Period - drug effects; Research design; Risk Factors; Substrates; Sugar; Tracers; Triglycerides
• ISSN: 0149-5992; 1935-5548; 1935-5548
• DOI: 10.2337/dc19-2331

Debate continues regarding the influence of dietary fats and sugars on the risk of developing metabolic diseases, including insulin resistance and nonalcoholic fatty liver disease (NAFLD). We investigated the effect of two eucaloric diets, one enriched with saturated fat (SFA) and the other enriched with free sugars (SUGAR), on intrahepatic triacylglycerol (IHTAG) content, hepatic de novo lipogenesis (DNL), and whole-body postprandial metabolism in overweight males.
Sixteen overweight males were randomized to consume the SFA or SUGAR diet for 4 weeks before consuming the alternate diet after a 7-week washout period. The metabolic effects of the respective diets on IHTAG content, hepatic DNL, and whole-body metabolism were investigated using imaging techniques and metabolic substrates labeled with stable-isotope tracers.
Consumption of the SFA diet significantly increased IHTAG by mean ± SEM 39.0 ± 10.0%, while after the SUGAR diet IHTAG was virtually unchanged. Consumption of the SFA diet induced an exaggerated postprandial glucose and insulin response to a standardized test meal compared with SUGAR. Although whole-body fat oxidation, lipolysis, and DNL were similar following the two diets, consumption of the SUGAR diet resulted in significant (
< 0.05) decreases in plasma total, HDL, and non-HDL cholesterol and fasting β-hydroxybutyrate plasma concentrations.
Consumption of an SFA diet had a potent effect, increasing IHTAG together with exaggerating postprandial glycemia. The SUGAR diet did not influence IHTAG and induced minor metabolic changes. Our findings indicate that a diet enriched in SFA is more harmful to metabolic health than a diet enriched in free sugars.