Does Adding Sugar to Coffee Negate Its Diabetes Protection?

TOPLINE:

Regular coffee consumption without any additives reduces the risk for type 2 diabetes (T2D) by 10% per cup, but this protection is significantly weakened when sugar or artificial sweeteners are added. Adding cream doesn’t affect coffee’s protective benefits, but adding coffee whitener shows a trend toward reduced protection.

METHODOLOGY:

• Although regular coffee consumption is associated with a lower risk for T2D, the effects of common additives like sugar and cream on this relationship have not been studied.
• Researchers analyzed the association between coffee consumption and the risk for T2D in 150,106 participants from three large prospective US-based cohort studies by reviewing the inclusion of sugar, artificial sweeteners, cream, or nondairy coffee whiteners; participants were followed up for 3,665,408 person-years.
• Participants provided updated information on food and beverage intake using validated semiquantitative food frequency questionnaires every 4 years, capturing more than 130 items including detailed coffee consumption and additive use patterns.
• Those diagnosed with T2D were requested to complete an additional questionnaire to specify their symptoms, diagnostic tests, and medications.
• Time-dependent Cox proportional hazards regression models with multivariable adjustment were used to calculate hazard ratios (HRs) for the association between coffee consumption, additive use, and the risk for T2D.

TAKEAWAY:

• Each additional cup of coffee consumed without additives was associated with a 10% lower risk for T2D (HR, 0.90; 95% CI, 0.89-0.92) in the pooled analysis of three cohorts.
• Adding sugar to coffee reduced this protective effect. Every cup of coffee consumed with sugar was associated with a 5% lower risk for T2D (HR, 0.95; 95% CI, 0.93-0.97); a 7% risk attenuation was observed with the artificial sweetener addition (HR, 0.93; 95% CI, 0.90-0.96).
• Cream use showed no significant impact on the protective association between coffee consumption and the risk for T2D; although nondairy coffee whiteners attenuated the association between coffee consumption and the risk for T2D, the attenuation was not statistically significant.
• As anticipated, coffee consumption with both artificial sweeteners and sugar did not offer any protection against the risk for T2D (HR, 0.96; 95% CI, 0.89-1.03).

IN PRACTICE:

“[The study] findings suggest that the use of additives, especially sugar and artificial sweeteners, may counteract the potential benefits of coffee consumption on diabetes,” the authors wrote.

SOURCE:

This study was led by Matthias Henn, Department of Nutrition, Harvard T.H. Chan School of Public Health, Boston. It was published online in The American Journal of Clinical Nutrition.

LIMITATIONS:

This study did not account for commercially available sugar-sweetened coffee beverages with a high caloric content. The habit of adding milk to coffee could not be examined as it was not assessed in the food frequency questionnaires. Information on coffee types such as bottled, brewed, canned, drip, ground, instant, liquid concentrate, or ready-to-drink coffee was not available. Given the observational nature of the analysis, causality could not be established. Additionally, since most participants were White healthcare professionals, the findings may not be generalizable to other populations.

DISCLOSURES:

This study received funding from the National Institutes of Health. The authors reported no conflicts of interest.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.