title: Controversies about sugars: results from systematic reviews and meta-analyses on obesity, cardiometabolic disease and diabetes.
abstract: Fructose-containing sugars are a focus of attention as a public health target for their putative role in obesity and cardiometabolic disease including diabetes. The fructose moiety is singled out to be the primary driver for the harms of sugars due to its unique endocrine signal and pathophysiological role. However, this is only supported by ecological studies, animal models of overfeeding and select human intervention studies with supraphysiological doses or lack of control for energy. The highest level of evidence from systematic reviews and meta-analyses of controlled trials has not shown that fructose-containing sugars behave any differently from other forms of digestible carbohydrates. Fructose-containing sugars can only lead to weight gain and other unintended harms on cardiometabolic risk factors insofar as the excess calories they provide. Prospective cohort studies, which provide the strongest observational evidence, have shown an association between fructose-containing sugars and cardiometabolic risk including weight gain, cardiovascular disease outcomes and diabetes only when restricted to sugar-sweetened beverages and not for sugars from other sources. In fact, sugar-sweetened beverages are a marker of an unhealthy lifestyle and their drinkers consume more calories, exercise less, smoke more and have a poor dietary pattern. The potential for overconsumption of sugars in the form of sugary foods and drinks makes targeting sugars, as a source of excess calories, a prudent strategy. However, sugar content should not be the sole determinant of a healthy diet. There are many other factors in the diet-some providing excess calories while others provide beneficial nutrients. Rather than just focusing on one energy source, we should consider the whole diet for health benefits.
authors.affiliation: Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, ON, Canada.|Toronto 3D Knowledge Synthesis and Clinical Trials Unit, Clinical Nutrition and Risk Factor Modification Centre, St. Michael's Hospital, Toronto, ON, Canada.
authors.forename: Tauseef A
authors.initials: TA
authors.lastname: Khan
authors.affiliation: Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, ON, Canada. john.sievenpiper@utoronto.ca.|Toronto 3D Knowledge Synthesis and Clinical Trials Unit, Clinical Nutrition and Risk Factor Modification Centre, St. Michael's Hospital, Toronto, ON, Canada. john.sievenpiper@utoronto.ca.|Division of Endocrinology and Metabolism, St. Michael's Hospital, Toronto, ON, Canada. john.sievenpiper@utoronto.ca.|Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, ON, Canada. john.sievenpiper@utoronto.ca.
authors.forename: John L
authors.initials: JL
authors.lastname: Sievenpiper
mesh_terms: D000818:Animals; D002318:Cardiovascular Diseases; D003924:Diabetes Mellitus, Type 2; D019422:Dietary Sucrose / Q000009:adverse effects*; D002149:Energy Intake; D019317:Evidence-Based Medicine; D005632:Fructose / Q000008:administration & dosage / Q000009:adverse effects; D006801:Humans; D015201:Meta-Analysis as Topic; D008659:Metabolic Diseases; D018673:Nutrition Policy; D009765:Obesity
chemical_list: D019422:Dietary Sucrose; D005632:Fructose
keywords: Cardiovascular disease; Diabetes; Fructose; Obesity; Overweight; Review; Sugars