Researchers uncover varying links between added sugar sources—like sweetened drinks, treats, and toppings—and risks for conditions such as heart failure, stroke, and aneurysms.

Study: Added sugar intake and its associations with incidence of seven different cardiovascular diseases in 69,705 Swedish men and women. Image Credit: Sorapop Udomsri / Shutterstock.com

Cardiovascular disease (CVD) is a leading cause of disease and death in Europe. Multiple studies support the association between CVD and unhealthy dietary habits; however, the impact of added sugar and different types of CVD remains unclear.

A recent study published in Frontiers in Public Health examines the risk of seven different types of CVDs associated with added and free sugar in foods and beverages.

The regulation of sugar intake

The incorporation of sugar into food products can cause consumers to overeat high-calorie, nutrient-empty foods at the cost of nutritious foods. Furthermore, added sugar increases the risk of tooth decay and weight gain.

Nordic guidelines recommend that less than 10% of total energy intake is provided by added and free sugar, including sugars naturally occurring in fruit juice concentrates, fruit juices, honey, and syrups. Likewise, both the American and World Health Organizations recommend less than 10% added and free sugar intake, respectively.

The European Food Safety Authority (EFSA) points to evidence that the risk of cardiometabolic disease rises with increased consumption of sugar-sweetened beverages (SSBs). Moderately strong evidence for obesity and high blood cholesterol levels with increased added and free sugar intake has also been reported.

Despite these observations, it remains unclear whether added and free sugar intake is directly associated with an increased risk of CVD. Moreover, the association with overall CVD risk does not correlate with the risk for individual cardiovascular conditions due to contradictory findings. Most studies that have examined this association have relied on a single measurement of added sugar consumption for their analyses and lack long-term follow-up data.

About the study

The current study examines how the consumption of added sugar, sugar-sweetened foods (SSFs), and SSBs is associated with the risk of ischemic stroke (IS), hemorrhagic stroke (HS), myocardial infarction (MI), heart failure (HF), aortic stenosis (AS), atrial fibrillation (AF), and abdominal aortic aneurysm (AAA).

The study included 69,705 individuals in two Swedish cohorts. Data on added sugar intake (ASI) were collected in 1997 and 2009 in over 60% of study participants. The average body mass index (BMI) was 25.3 kg/m2, with a mean age of 59.9 years.

SSFs were classified as treats such as pastries, ice cream, and chocolates or toppings like marmalades, jams, sugar, and honey. SSBs included sweetened sodas and fruit drinks, excluding pure fruit juices.

The mean ASI was 9.1% of energy intake (E%) in 1997. Being male, doing more exercise, and having less education were associated with greater ASI, along with older age and higher energy intake.

Low-to-moderate added sugar intake

After compensating for the effects of age, sex, and energy intake, ASI was associated with all seven CVDs; however, these associations were weakened after adjusting for lifestyle factors, BMI, and diet.

The highest category of ASI, over 20 E%, was associated with a 31% increased risk of AAA compared to the lowest intake category of five E% or less. At over 15-20 E%, the risk of IS was 9% higher.

For most outcomes, the lowest ASI was associated with the highest risk. The risk for most CVDs was lowest at 5-7.5 E%. Thus, MI, AF, IS, HF, and AS risks were reduced by 5-9% in this category compared to the lowest intake.

With ASI exceeding 7.5-10 E%, the risk of HF and AF was reduced by 6% and 4%, respectively. At over 10-15 E%, the risk of HF, AF, and AS decreased by 5%, 4% and 17% respectively. Higher ASI was associated with a greater AAA and IS risk among obese individuals, whereas higher HF risk was observed in normal-weight individuals.

SSB intake

SSB intake was linearly associated with the risk of IS, HF, AF, and AAA. Consuming over eight SSB servings each week increased AF, IS, HF, and AAA risk by 11%, 18%, 19%, and 31%, respectively.

Analysis of the 2009 survey indicated an increased risk of IS and HF with greater artificially sweetened beverage consumption but not SSBs. This could be due to the small sample size for sweetened beverages, as current literature indicates a positive correlation of SSBs with increased CVD risk.

SSF consumption

The lowest CVD risk was observed in the highest treat intake category, whereas the highest risk was observed among those who consumed two or fewer treats each week.

Although the mechanism remains unclear, this association might be due to better social health. In Sweden, coffee and pastries are part of fika, customary social gatherings, and may not indicate an overall unhealthy lifestyle.

Topping intake showed a mixed pattern, as those who consumed toppings had a 10% reduced risk of HF as compared to the lowest intake category. AS risk was reduced by 14-20% with increasing ASI, whereas AAA risk increased by 34%.

Conclusions

The study findings do not support lowering the recommendations for added sugar intake to below five E%.”

A low to moderate intake of added sugar is associated with lower CVD risk at 5-7.5 E% as compared to either over five E% or 10 E%. Both the sugar source and the studied clinical outcome affect the nature and direction of the association.

Future studies are needed to elucidate the mechanisms involved in these associations and the role of body weight. Furthermore, confounding factors like sodium intake, an independent CVD risk predictor, should also be considered.