Excess consumption of sugary drinks interlinked with high breast cancer risk

A new observational study finds a link between the consumption of sugary drinks, including 100% fruit juices, and the risk of cancer

Image Source: Google
Image Source: Google

A study published by The BMJ today reports a possible association between higher consumption of sugary drinks and an increased risk of cancer.

For some time now, researchers have been linking sugary drinks with a wide range of health risks.

Obesity, type 2 diabetes, and cardiovascular disease are only some of the conditions that previous studies have associated with sweetened drinks.

Some studies in rodents have suggested that the added sugar in soft drinks can drive the spread of cancer and fuel tumour growth.

Now, new research further explores the link between sugary drinks and cancer. The observational study, appearing in The BMJ, finds an association between high intake of sugary drinks and cancer.

Eloi Chazelas, from the Sorbonne Paris Cité Epidemiology and Statistics Research Center in France, is the first author of the study.

Studying sugary drinks and cancer risk

Chazelas and team examined the links between the intake 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, syrups, fruit drinks, 100% fruit juices without any added sugar, milk-based sugary drinks, sports drinks, and energy drinks.

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 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 looked at the risk of “overall, breast, prostate, and colorectal cancer.”

Chazelas and colleagues accounted for potential confounders, including age, sex, education, hereditary risk of cancer, and lifestyle factors – such as smoking behaviour and exercise patterns.

A 22% higher risk of breast cancer

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 cancer.

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 separately, these also elevated the risk of overall cancer and breast cancer. However, the study found no links with colorectal cancer or prostate cancer.

By contrast, diet drinks did not increase cancer risk. The scientists explain that people who consumed diet drinks did so in very small amounts, so they suggest interpreting this particular result with caution.

This is an observational study, so can’t establish cause, and the authors say they cannot rule out some misclassification of beverages or guarantee detection of every new cancer case.

Nevertheless, the study sample was large and they were able to adjust for a wide range of potentially influential factors. What’s more, the results were largely unchanged after further testing, suggesting that the findings withstand scrutiny.

These results need replication in other large scale studies, say the authors.

“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,” they conclude.

Source: Medical News Today