Intake of Sugar Sweetened Beverages Linked with Alzheimer's – Study 

10/12/07 Compelling evidence indicates that excess consumption of sugar-sweetened beverages plays an important role in the epidemic of obesity, a major risk factor for type 2 diabetes mellitus (T2DM), according to a paper to be published in the Journal of Biological Chemistry. T2DM has been associated with a higher incidence of Alzheimer’s disease (AD). High fat diets promote AD-like pathology in mice. It is not known whether consumption of excess sugar as in calorically sweetened beverages with an otherwise normal diet affects the development of AD.

In the present study, researchers from the University of Alabama at Birmingham provided 10% sucrose-sweetened water to a transgenic mouse model of AD with a normal rodent diet. Compared to the control mice with no sucrose added in the water, the sucrose group gained more body weight and developed glucose intolerance, hyperinsulinemia, and hypercholesterolemia. These metabolic changes were associated with the exacerbation of memory impairment and a 2 to 3-fold increase in insoluble amyloid-beta protein (Abeta) levels and deposition in the brain.

The researchers further showed that the levels of expression and secretase-cleaved products of amyloid-beta precursor protein were not affected by sucrose intake. The steady-state levels of insulin-degrading enzyme did not change significantly, whereas there was a 2.5-fold increase in brain apoE levels. Therefore, we concluded that the upregulation of apoE accelerated the aggregation of Abeta, resulting in the exacerbation of cerebral amyloidosis in sucrose-treated mice. These data underscore the potential role of dietary sugar in the pathogenesis of AD and suggest that controlling the consumption of sugar-sweetened beverages may be an effective way to curtail the risk of developing AD.