Soft drinks and diabetes risk
We all know that sugar-sweetened drinks are not ‘good’ for us, but are they really ‘bad’ for us?
According to a recent study, one soft drink a day increases type 2 diabetes risk by a fifth.
Use of caloric sweeteners has increased around the world, with sugar-sweetened beverages accounting for a major part of this increase. Parallel to this increase, there has been an increase in the prevalence of obesity and type 2 diabetes worldwide. Diabetes, if not properly managed, is associated with serious complications including heart disease, stroke, blindness, kidney disease and amputations leading to disability and premature mortality.
The majority of epidemiological studies published so far on the association between sweet drinks and diabetes risk are based on North American cohort studies. (A cohort study follows a group of people over a period of time to see how their exposures to a risk factor affect their outcomes). The consumption of sweet beverages in Europe appears to be lower than in the USA, though it seems to be rising. A recent study led by Dr Romaguera at Imperial College London and researchers from the InterAct consortium, which has been widely reported by the media, looked at the association between the consumption of sweet drinks (sugar-sweetened soft drinks such as cola, artificially-sweetened drinks such as diet cola plus fruit juices and nectars) and type 2 diabetes in European adults. They found that each 336ml of sugar-sweetened soft drink – roughly one can – drunk per day increased the risk of type 2 diabetes by 22%. This increase in risk fell slightly to 18% after accounting for total energy intake and body mass index (BMI), suggesting that the effect of sugar-sweetened soft drinks on diabetes is not purely down to body weight. People who drank more artificially-sweetened soft drinks were also more likely to get type 2 diabetes, but this association appeared to be because participants with a higher BMI, who are more likely to develop diabetes, tend to drink more artificially-sweetened drinks. Drinking pure fruit juice or nectar (diluted juices, sometimes with additives) was not associated with diabetes risk.
The increase in risk of type 2 diabetes among sugar-sweetened soft drink consumers in Europe is similar to that found in America, where a meta-analysis of previous studies found that high consumers of sweetened beverages (1–2 servings/day) had a 26% greater risk of developing type 2 diabetes than low consumers (none or <1 serving/month).
Sweetened soft drinks are thought to lead to weight gain and obesity by virtue of their high sugar content, low satiety potential and incomplete compensation for total energy at subsequent meals after intake of liquid calories, leading to positive energy balance. Due to the high content of rapidly absorbable carbohydrates such as sucrose (50% glucose and 50% fructose) and high-fructose corn syrup (most often 45% glucose and 55% fructose), in conjunction with the large volumes consumed, sweetened soft drinks may increase the risk of type 2 diabetes and metabolic syndrome not only through obesity but also by increasing dietary glycaemic load, leading to insulin resistance. Furthermore, endogenous compounds in sweetened soft drinks, such as advanced glycation end products, produced during the process of caramelisation in cola-type beverages may also affect pathophysiological pathways related to type 2 diabetes and the metabolic syndrome.
Additional metabolic effects of these beverages may also lead to hypertension and promote the accumulation of visceral adipose tissue and of ectopic fat , resulting in the development of high triglycerides and low HDL cholesterol and small, dense LDL, although the specific metabolic effects of fructose versus glucose remain to be further examined.
Although the European study had some limitations, it appears to confirm the health risks of regularly consuming soft drinks. Most popular soft drinks now come in a sugar-free alternative, so these would certainly seem to be the healthier choice. Alternatively, a glass of water is both healthier and a lot cheaper. As well as reducing or cutting out sugary drinks, the risk of developing type 2 diabetes could be significantly reduced by combining regular physical activity with a healthy balanced diet rich in fruit and vegetables and low in fat, sugar and salt.
By Victoria Trowse
1. Popkin B.M. and Nielsen S.J. (2003). The sweetening of the world’s diet. Obes Res 11: 1325–1332.
2. Farag Y.M. and Gaballa M.R. (2011). Diabesity: an overview of a rising epidemic. Nephrol Dial Transplant 26: 28–35.
3. Diabetes in the UK April 2012. Key statistics on diabetes. http://www.diabetes.org.uk/Professionals/Publications-reports-and-resources/Reports-statistics-and-case-studies/Reports/Diabetes-in-the-UK-2012/ (accessed on 1 June 2013).
4. Naska A., Bountziouka V., Trichopoulou A. (2010). Soft drinks: time trends and correlates in twenty-four European countries. A cross-national study using the DAFNE (Data Food Networking) databank. Public Health Nutr 13: 1346–1355.
5.Consumption of sweet beverages and type 2 diabetes incidence in European adults: results from EPIC-InterAct. Diabetologia 2013.
6. Malik V.S., Popkin B.M., Bray G.A., Despres J.P., Willett W.C., Hu F.B. (2010). Sugar-sweetened beverages and risk of metabolic syndrome and type 2 diabetes: a meta-analysis. Diabetes Care 33: 2477–2483.
7. Malik V.S., Schulze M.B., Hu F.B. (2006). Intake of sugar-sweetened beverages and weight gain: a systematic review. Am J Clin Nutr. 84(2): 274-88.
8. Gibson S. (2008). Sugar-sweetened soft drinks and obesity: a systematic review of the evidence from observational studies and interventions. Nutrition Research Reviews, 21: 134-147.
9. Schulze M.B., Liu S., Rimm E.B., Manson J.E., Willett W.C., Hu F.B. (2004). Glycemic index, glycemic load, and dietary fiber intake and incidence of type 2 diabetes in younger and middle-aged women. Am J Clin Nutr 80: 348–356.
10. Uribarri J., Stirban A., Sander D., Cai W., Negrean M., Buenting C.E., Koschinsky T., Vlassara H. (2007). Single oral challenge by advanced glycation end products acutely impairs endothelial function in diabetic and non-diabetic subjects. Diabetes Care 2007; 30: 2579–2582.
11. Stanhope K.L., et al (2009). Consuming fructose-sweetened, not glucose-sweetened, beverages increases visceral adiposity and lipids and decreases insulin sensitivity in overweight/obese humans. J. Clin Invest 119: 1322–1334.