Most systematic review s and meta-analyses from controlled feeding trials have shown that fructose-containing sugars in isocaloric exchange for other carbohydrates do not show evidence of harm and , in the case of fructose , may even have advantages for glycaemic control , especially at small doses .
Nevertheless , trials in which fructose-containing sugars supplement diets with excess energy have shown adverse effects , effects that appear more attributable to the excess energy than the sugar .
There is no unequivocal evidence that fructose intake at moderate doses is directly related with adverse metabolic effects , although there is potentially cause for concern where fructose is provided at high doses or contributes excess energy to diets .
Concerns are growing regarding the role of dietary sugars in the development of obesity and cardiometabolic diseases , including diabetes .
High-fructose corn syrup ( HFCS ) and sucrose are the most important dietary sweeteners .
Both HFCS and sucrose have overlapping metabolic actions with adverse effects attributed to their fructose moiety .
Ecological studies have linked the rise in fructose availability with the increases in obesity and diabetes worldwide .
This link has been largely underpinned by animal models and select human trials of fructose overfeeding at high levels of exposure .
Whole-grain intake and the risk of type 2 diabetes: a prospective study in men.
BACKGROUND Certain dietary components may play a role in the prevention of type 2 diabetes . OBJECTIVE We examined prospect ively the associations between whole- and refined-grain intake and the risk of type 2 diabetes  in a large cohort of men . DESIGN Men from the Health Professionals Follow-up Study without a history of diabetes or cardiovascular disease in 1986 ( n = 42898 ) were followed for < /=12 y. Intakes of whole and refined grains , measured every 4 y by use of food-frequency question naires , were used to predict subsequent type 2 diabetes risk through multivariate analysis . RESULTS We ascertained 1197 cases of incident type 2 diabetes . After adjustment for age ; physical activity ; cigarette smoking ; alcohol consumption ; family history of diabetes ; and fruit , vegetable , and energy intakes , the relative risk of type 2 diabetes was 0.58 ( 95 % CI : 0.47 , 0.70 ; P for trend < 0.0001 ) comparing the highest with the lowest quintile of whole-grain intake . The association was moderately attenuated when additionally adjusted for body mass index ( relative risk : 0.70 ; 95 % CI : 0.57 , 0.85 ; P for trend = 0.0006 ) . Intake of refined grains was not significantly associated with risk of type 2 diabetes . After further adjustment for magnesium intake , cereal fiber intake , and glycemic load , the association between whole grains and type 2 diabetes was attenuated and the trend no longer significant . CONCLUSIONS In men , a diet high in whole grains is associated with a reduced risk of type 2 diabetes in men that may be mediated by cereal fiber . Efforts should be made to replace refined-grain with whole-grain foods
Most systematic review s and meta-analyses from controlled feeding trials have shown that fructose-containing sugars in isocaloric exchange for other carbohydrates do not show evidence of harm and , in the case of fructose , may even have advantages for glycaemic control , especially at small doses .
Nevertheless , trials in which fructose-containing sugars supplement diets with excess energy have shown adverse effects , effects that appear more attributable to the excess energy than the sugar .
There is no unequivocal evidence that fructose intake at moderate doses is directly related with adverse metabolic effects , although there is potentially cause for concern where fructose is provided at high doses or contributes excess energy to diets .
Concerns are growing regarding the role of dietary sugars in the development of obesity and cardiometabolic diseases , including diabetes .
High-fructose corn syrup ( HFCS ) and sucrose are the most important dietary sweeteners .
Both HFCS and sucrose have overlapping metabolic actions with adverse effects attributed to their fructose moiety .
Ecological studies have linked the rise in fructose availability with the increases in obesity and diabetes worldwide .
This link has been largely underpinned by animal models and select human trials of fructose overfeeding at high levels of exposure .