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In a nutshell
Not all sugars affect heart health the same way. While sugar-sweetened beverages significantly increase cardiovascular risks, moderate consumption of treats like pastries and chocolate might have protective effects, especially in social settings.
The study found a “sweet spot” for total added sugar intake between 5-7.5% of daily calories, challenging the assumption that less sugar is always better. For a 2,000-calorie diet, this means about 25-37.5 grams of added sugar per day.
Your weight matters when it comes to sugar’s impact on heart health. Overweight individuals (BMI over 25) showed higher risks of stroke and aortic aneurysm with increased sugar intake, while normal-weight individuals primarily showed increased heart failure risk.
LUND, Sweden — Next time someone tells you to cut all sugar from your diet, you might want to share this story. Swedish researchers tracking nearly 70,000 people for twenty years have uncovered some unexpected truths about sugar consumption and heart health that challenge the “sugar is always bad” narrative.
While public health guidelines typically recommend limiting added sugar intake to less than 10% of daily calories, this study suggests the relationship between sugar and heart health isn’t as straightforward as “less is always better.” The researchers from Lund University found that participants consuming between 5% and 7.5% of their daily calories from added sugar generally had lower risks of several cardiovascular conditions, including ischemic stroke, heart attack, heart failure, and atrial fibrillation, compared to those consuming less than 5% of calories from added sugar.
For perspective, in a 2,000-calorie daily diet, 5% to 7.5% would translate to about 25-37.5 grams of added sugar – roughly the amount in one to one-and-a-half cans of regular soda.
Tale Of Two Sweets
The study’s most striking finding was how different sources of added sugar affected heart health. Sugar-sweetened beverages emerged as particularly problematic, with higher consumption linked to increased risks of several serious conditions. People drinking more than eight servings of sweetened beverages per week faced a 19% higher risk of ischemic stroke, an 18% higher risk of heart failure, an 11% higher risk of atrial fibrillation, and a 31% higher risk of abdominal aortic aneurysm (a dangerous bulging of the main blood vessel carrying blood from the heart) compared to those drinking one serving or less.
While the study found some protective effects from sugars, scientists agree that there are no health benefits to drinking soda or other sugary beverages. (© Bill – stock.adobe.com)
However, in an unexpected twist, lower consumption of treats like pastries, ice cream, and chocolate was associated with higher cardiovascular risks across all studied conditions. This seemingly counterintuitive finding might be explained by Sweden’s unique “fika” culture – a daily social custom of sharing coffee and pastries with friends and colleagues. Some researchers speculate that moderate treat consumption in this context might be a marker of social connection and overall well-being, rather than just a dietary factor.
“Liquid sugars, found in sweetened beverages, typically provide less satiety than solid forms — they make you feel less full — potentially leading to overconsumption,” says corresponding author Suzanne Janzi, a PhD candidate at Lund University, in a statement. “Context also matters — treats are often enjoyed in social settings or special occasions, while sweetened beverages might be consumed more regularly.”
The Science Behind The Sugar
The study, published in Frontiers in Public Health, tracked 69,705 Swedish adults (47.2% women) aged 45-83 years between 1997 and 2019. What sets this research apart is its detailed approach to measuring sugar intake. Participants completed comprehensive dietary questionnaires in both 1997 and 2009, allowing researchers to analyze how their sugar consumption patterns changed over time. The team examined seven specific types of cardiovascular disease, ranging from different kinds of stroke to heart rhythm problems.
During the study period, 25,739 participants developed at least one form of cardiovascular disease. The researchers found that total added sugar intake showed clear positive associations with two specific conditions: ischemic stroke (caused by blocked blood vessels in the brain) and abdominal aortic aneurysm. This means that as sugar consumption increased, so did the risk of these particular conditions.
Body weight played a significant role in how sugar affected heart health. For people with a body mass index (BMI) over 25 (considered overweight), higher sugar intake was associated with increased risks of abdominal aortic aneurysm and ischemic stroke. However, for those with a BMI between 18.5 and 25 (considered normal weight), higher sugar intake was primarily associated with increased heart failure risk.
The Bittersweet Truth
What makes this study particularly valuable is its unprecedented scope and detail. Although previous research has often focused solely on sugar-sweetened beverages or treated all added sugars as equivalent, this study demonstrates that the relationship between sugar and heart health is far more nuanced. The researchers were able to track participants’ health outcomes through Sweden’s comprehensive national health registers, providing highly reliable data about disease diagnoses.
Still, study authors warn that because the research only focuses on Swedish individuals, the results may not apply to everyone.
“Our findings are based on a Swedish population, which may have dietary habits and lifestyle factors that differ from those in other populations,” notes Janzi. “Particularly relevant in this context is the social custom of ‘fika’ — regular coffee and pastry breaks that are deeply embedded in Swedish culture. These results may not directly translate to other populations with different dietary cultures.”
Just as a master baker knows that the perfect recipe requires balance rather than elimination of ingredients, this study suggests that our approach to dietary sugar might benefit from similar nuance. While sugar-sweetened beverages remain firmly in the “consume with caution” category, the occasional shared pastry might just be food for the heart in more ways than one.
Paper Summary
Methodology
This study used data from two large Swedish cohorts: the Swedish Mammography Cohort and the Cohort of Swedish Men. Participants completed detailed food frequency questionnaires in 1997 and 2009, reporting their consumption of various foods and beverages. The researchers calculated added sugar intake by subtracting naturally occurring sugars from total sugar consumption. They tracked participants’ health outcomes through national health registers until 2019, using statistical models to account for various lifestyle factors and potential confounders.
Results
The study found different patterns for different types of cardiovascular disease and sugar sources. Sugar-sweetened beverages showed the clearest negative impact, with higher consumption linked to increased risk of several heart conditions. Very low sugar intake (less than 5% of calories) was associated with higher risks of most conditions compared to moderate intake (5-7.5%). Surprisingly, lower consumption of treats was linked to higher cardiovascular risks, possibly due to social and cultural factors.
Limitations
The study relied on self-reported dietary information, which can be subject to misreporting. About 39% of participants didn’t complete the 2009 follow-up questionnaire. The findings might not apply to other populations with different dietary patterns and cultural practices. The unexpected associations with treat consumption might reflect social factors rather than direct dietary effects.
Key Takeaways
The study suggests that the relationship between added sugar and cardiovascular health is complex and depends on the sugar source and type of heart condition. While sugar-sweetened beverages should be limited, extremely low sugar intake might not be beneficial. The findings challenge the simple “less is better” approach to sugar consumption and highlight the importance of considering cultural and social contexts in dietary recommendations.
Funding and Disclosures
The research was funded by several Swedish organizations, including the Swedish Research Council, the Heart and Lung Foundation, and the Albert Påhlsson Foundation. The authors declared no conflicts of interest. The study used resources from SIMPLER (Swedish Infrastructure for Medical Population-based Life-course Environmental Research) and computational resources from UPPMAX (Uppsala Multidisciplinary Center for Advanced Computational Science).