The regular consumption of sugar-sweetened drinks is associated with weight gain. This seems an unequivocal finding. There may be multiple reasons for this and not just the taking in a lot excess sugar calories. You might expect a quick fix of sugar to suppress appetite in a similar way to eating a meal but this seems not to be the case. There appears to be a lack of compensatory reduction in food intake in subsequent meals. This translates into positive energy balance at the end of the day and this will add up over time and translate into gradual weight gain.
Although it has been estimated that a significant proportion of the effects of sugary drinks on diabetes incidence is mediated through the influence of weight gain this seems to be not the only mechanism. Sugary drinks with their almost immediate result in causing high blood glucose spikes have also been shown to adversely affect insulin secretion from the pancreas. This in turn disturbs the body’s regulation of glucose metabolism, a disturbance that encourages the development of diabetes. In addition, sugary soft drinks have also been shown to adversely affect cholesterol profiles and raise blood pressure. These are the very things you don’t want on top of diabetes and it may not be surprising therefore that we find fizzy drinks described in some newspapers as evil.