A new observational study identifies a link between the consumption of sugary drinks, including 100% fruit juices, and the risk of cancer.
Extensive studies surrounding the impact of sugary drinks on cardiometabolic health have associated sweetened beverages with a wide range of health risks such as obesity, type 2 diabetes and cardiovascular disease. However, some studies in rodents have suggested that the added sugar in soft drinks can promote the spread of cancer and fuel tumour growth.
New research further explores the link between sugary drinks and cancer. The observational study, appearing in The BMJ, marks a positive correlation between high intake of sugary drinks and risk of cancer.
Eloi Chazelas, from the Sorbonne Paris Cité Epidemiology and Statistics Research Center in France, and team examined the links between the consumption of sugary drinks and various forms of cancer in 101,257 French adults aged 42 years, on average. The researchers obtained the data from the NutriNet-Santé study.
The drinks they examined included “sugar-sweetened beverages” such as soft drinks, fruit drinks, 100% fruit juices without any added sugar, milk-based sugary drinks, sports drinks, energy drinks, and syrups.
The researchers also considered artificially-sweetened drinks, that is, “all beverages containing non-nutritive sweeteners, such as diet soft drinks, sugar-free syrups, and diet milk-based beverages.”
Using web-based 24 hour online food questionnaires, the researchers assessed the participants’ consumption of 3,300 different kinds of foods and drinks. Furthermore, clinical observation of the participants continued for up to 9 years.
During this time, the researchers examined the participants’ risk of “overall, breast, prostate, and colorectal cancer.”
Chazelas and colleagues accounted for potential confounding variables, including age, sex, education, hereditary risk of cancer, and lifestyle factors — such as smoking status and exercise patterns.
Over the follow-up period 2,193 people developed cancer for the first time; they were 59 years old at the time of diagnosis, on average. Among all these cases were 693 of breast cancer, 291 of prostate cancer, and 166 colorectal cancers.
The analysis revealed that for a daily increase of 100 millilitres in the intake of sugary drinks, the risk of overall cancer rose by 18%, and the risk of breast cancer increased by 22%.
When the researchers analysed the risk for 100% fruit juices specifically, these also elevated the risk of overall cancer and breast cancer. However, the study found no links with colorectal cancer or prostate cancer.
In contrast, diet drinks did not increase cancer risk. The scientists explain that people who consumed diet drinks did so in very small amounts, and subsequently advice discretion in interpreting this particular result.
The researchers conclude: “These data support the relevance of existing nutritional recommendations to limit sugary drink consumption, including 100% fruit juice, as well as policy actions, such as taxation and marketing restrictions targeting sugary drinks, which might potentially contribute to the reduction of cancer incidence.”