Prospective associations and population impact of sweet beverage intake and type 2 diabetes, and effects of substitutions with alternative beverages

O’Connor L., Imamura F, Lentjes MAH et al.,
Diabetologia DOI 10.1007/s00125-015-3572-1

Background

Consumption of sugar-sweetened beverages (SSB) has been linked to a higher risk of type 2 diabetes (T2DM). In the European Prospective Investigation into Cancer and Nutrition (EP-IC)-Interact Study, this relation was found to be independent of several confounding factors including adiposity [1]. Also null associations between artificially sweetened beverages (ASB) and incident T2DM have been described, and the influence of confounding or reverse causality by adiposity remains unclear. The evidence for the effect of fruit juice consumption is limited and inconsistent. Moreover, the associations of other SSB like sweetened tea, coffee and milk beverages with T2DM are uncertain.
Public health agencies recommend limiting SSB consumption, but evidence is insufficient on which beverages may constitute appropriate replacement.
Research on SSB consumption generally relies on the use of dietary data obtained with food frequency questionnaires, which do not specify individual beverage types, or sugar added to coffee and tea. Using prospective food diaries can provide more detailed dietary information.
This study therefore used 7 day food diaries to examine the associations between different types of sweetened drinks and incident T2DM more precisely, also considering the contribution of SSB to total energy intake (%TEI) and how substitution by alternative beverages could impact the incidence of T2DM. 24652 individuals of the EPIC-Norfolk study [2] agreed to and were eligible to participate.  

Main results

• During 248 264 person-years, 847 T2DM diagnoses were made.
• After adjustment for confounders and TEI, a higher T2DM incidence was seen per serving of soft drinks (HR: 1.21, 95%CI: 1.05-1.39), sweetened-milk beverages (HR: 1.22, 95%CI: 1.05-1.43) and ASB (HR: 1.22, 95%CI: 1.11-1.33).
  The association of ASB was attenuated to a non-significant relation (HR: 1.06, 95%CI: 0.93-1.20) by further adjustment for BMI and waist circumference, while those for soft drink (HR: 1.14, 95%CI: 1.01-1.32) and sweetened-milk beverages (HR: 1.27, 95%CI; 1.09-1.48) remained statistically significant.
• Intake of sweetened tea or coffee and fruit juice were not significantly associated with incident T2DM.
• A positive linear association was seen between total sweet beverage intake (%TEI) and incident T2DM, which was statistically significant above 1%TEI. Each 5% higher TEI was associated with 18% (95%CI: 11-26) higher incidence of T2DM.
• If all adults reduced sweet beverage intake to below 10%TEI, the population-attributable fraction (PAF) was estimated as 3% (95%CI: 1-7), as 7% (95%CI; 1-13) if intake was lowered to less than 5%TEI and as 15% (95%CI; 3-25) if intake was lowered to less than 2%TEI.
• Substituting drinking soft drinks and sweetened milk beverages with drinking water was estimated to reduce the incidence of T2DM (HR: 0.86, 95%CI: 0.74-0.99 and HR: 0.80, 95%CI: 0.67-0.94), while substitution with ASB did not lower the incidence.  
  Consuming unsweetened tea or coffee instead of soft drinks and sweetened-milk beverages was also estimated to reduce T2DM incidence (HR: 0.86, 95CI: 0.73-0.99 and HR: 0.75, 95%CI: 0.63-0.86). Replacing sweetened by unsweetened tea or coffee also appears to reduce T2DM incidence (HR: 0.96, 95%CI: 0.92-0.99).

Conclusion

Analysis of detailed dietary information from prospective 7 day food diaries shows a positive association between soft drinks and incident T2DM, but null relations between artificially sweetened beverages and fruit juice and T2DM. Also sweetened-milk beverages showed a link with higher T2DM incidence. A positive linear relation between the contribution of %TEI from total sweet beverages and T2DM was observed. It was estimated that 3-15% of incident diabetes cases may be prevented if consumption of sweet beverages would be reduced to below 10-2%TEI. Water or unsweetened tea or coffee appear good alternatives to soft drinks and sweetened-milk beverages to lower T2DM incidence.

Find this article online at Diabetologia

References

1. The InterAct Consortium (2013) Consumption of sweet beverages and type 2 diabetes incidence in European adults: results  from EPIC-InterAct. Diabetologia 56:1520–1530
2. Day N, Oakes S, Luben R et al (1999) EPIC-Norfolk: study design and characteristics of the cohort. European Prospective Investigation of Cancer. Br J Cancer 80(Suppl 1):95–103