Coffee’s Heart Health Link Looks Stronger Without Sweeteners

Yet the new paper points to an important and oft-repeated caveat: sugar and other sweeteners obscure the health picture. “Moderate intakes of unsweetened coffee and tea were each associated with a lower risk of incident CVD, whereas sweetened types did not show protective associations,” the researchers wrote. “These findings suggest that sweetener use should be considered when evaluating the cardiovascular relevance of coffee and tea consumption.”

Large Cohort

The paper, titled “Associations of Unsweetened and Sweetened Coffee and Tea Consumption with Incident Cardiovascular Disease: A Large Prospective Cohort Study,” drew from 167,142 UK Biobank participants who did not have cardiovascular disease at the start of the study.

Participants completed repeated online food-and-drink surveys reporting what they had consumed in the previous 24 hours. Researchers then tracked their health records for a median of 11.1 years.

During that period, 14,395 people developed cardiovascular disease, defined in the study as a first recorded case of coronary heart disease, stroke or heart failure.

Unsweetened vs. Sweetened

The clearest coffee finding came among people drinking more than two and up to three daily “units” of unsweetened coffee, as defined by the study’s dietary questionnaire. Compared with non-consumers, that group had a 19% lower risk of developing cardiovascular disease.

People drinking more than three and up to five units per day had a 14% lower risk, while people drinking more than five units per day did not show a statistically significant reduction. In plain terms, the results traced a U-shaped curve: Some unsweetened coffee was associated with lower risk, the strongest association appeared around moderate intake, and the apparent benefit disappeared at the highest intake level. Sweetened coffee told a different story.

The researchers found no lower cardiovascular disease risk associated with sweetened coffee at any intake level. Tea followed a similar pattern, with unsweetened tea linked to lower risk across intake categories, while high sweetened tea intake — more than five units per day — was associated with higher risk.

Consistent with Previous Work

In April, DCN covered a separate UK Biobank-based study that found unsweetened coffee was associated with lower cardiovascular disease risk, while coffee with sugar or artificial sweeteners was not. That study found the strongest association among people drinking two to three cups of unsweetened coffee per day.

The new paper was published about three weeks before the American Heart Association issued a scientific statement concluding that up to 400 milligrams of caffeine per day — roughly three to five 8-ounce cups of regular caffeinated coffee without additives — is generally safe for most adults and may be associated with lower risk of some cardiovascular conditions. Author affiliations for the new study included Zhejiang University School of Medicine, the Hangzhou Center for Disease Control and Prevention and the Harvard T.H.

Chan School of Public Health. The study was funded by the National Key Research and Development Program of China.

The authors declared no competing interests. Comments?

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