Meta-Analysis of Sugar and Type 2 diabetes Published

Tsilas et al., present research findings of a systematic review and meta-analysis in the article “Relation of total sugars, fructose and sucrose with incident type 2 diabetes: a systematic review and meta-analysis of prospective cohort studies” published in the Canadian Medical Association Journal. The authors evaluated data from 9 publications reporting results of 15 cohort studies involving 251,261 participants and 16,416 cases of type 2 diabetes. Study participants were from 11 countries and had a median age of 52.6 years. Median follow-up was 12 years for total sugars (interquartile range [IQR], 4–12 yr), 6.3 years for fructose (IQR 6–12 yr) and 6.2 years (IQR 6–12 yr) for sucrose. The median intakes for total sugars, fructose and sucrose were 65 g/d (IQR 25.8–100 g/d), 9.7 g/d (IQR 6–25.8 g/d) and 25.8 g/d (IQR 22.5–28.5 g/d), respectively, in the lowest quantile of intake and 137 g/d (IQR 57.2–194.4 g/d), 35.2 g/d (IQR 28.8–57.2 g/d) and 78 g/d (IQR 57.2–102 g/d) for the highest quantile of intake, median intakes for total sugars, fructose and sucrose. The authors report that pooled analyses showed that the intakes of total sugars and fructose were not associated with type 2 diabetes, while intake of sucrose was associated with an 11% decrease in type 2 diabetes. The authors state “The lack of an adverse association is difficult to reconcile with the biological mechanisms and ecological observations linking fructose-containing sugars to type 2 diabetes” but suggest that residual confounding from reverse causality or the possibility that sugar-sweetened beverages (SSBs) are a marker of an unhealthy lifestyle may explain their findings. Additionally, the study findings may reflect important contributions of sugar, fructose, and sucrose from other food sources. Nonetheless, these findings do not support a hypothesis that fructose does not mediate the positive association seen between SSBs and diabetes. The authors conclude “In the absence of a clear signal for harm, sugars alone do not appear to explain the relation between sugar-sweetened beverages and type 2 diabetes. More “food-based” research is needed to assess whether the same relation holds for other important food sources of sugars, such as grain and grain-based products, fruit and fruit products, and dairy and dairy products.”