“The sugar will rot your teeth, soda is bad for you” – we all have heard many forms of this disclaimer from parents or older relatives. However, a new study suggests that they may be right. According to a study published in the British Medical Journal (BMJ), the consumption of sugary drinks is associated with an increased risk of cancer.
A team of researchers in France found that intake of even just 100 millilitres of soft drinks or fruit juice a day can lead to an increased risk of cancer. The study was carried out by Inserm, a public research organisation from France. The researchers observed 1,01,257 healthy French adults (21,264 men and 79,993 women), who were 18 years or older, with the average age being 42 years old.
Researchers were aiming to assess the association between consuming sugary beverages and the risk of developing any form of cancer, and additionally, researchers also noted the risk of developing breast, prostate, and bowel (colorectal) cancers in connection with consuming such products. The participants were required to complete a minimum of 2 dietary questionnaires with questions designed to measure the intake of over 3000 types of food and drinks. They were followed up for 9 years, between the years of 2009 and 2018.
They then calculated the daily intake of sugary drinks (including 100 per cent fruit juices and soft drinks as well as diet drinks made with artificial sweeteners) and recorded the number of participants who reported having been diagnosed with cancer, which was then confirmed by medical records and health insurance databases. After this, the researchers took into account well-known risk factors for cancer, including age, sex, educational level, family history of cancer, smoking status and physical activity levels, before coming to a final conclusion.
What did the study reveal?
At the time of the follow-up, the researchers noted that 2,193 first cases of cancer were diagnosed (693 breast cancers, 291 prostate cancers, 166 colorectal cancers). Based on the results of the study, the scientists concluded that a mere 100 millilitres intake of a beverage that contains sugar (or of a soft drink or fruit juice) was associated with an overall 18 per cent increase in the development of any cancer, and a 22 per cent increased risk of developing breast cancer specifically.
The researchers noted that as there were not enough people in the study who drank diet drinks regularly, they were unable to make a statement regarding the effects of these drinks and the risk of cancer. Diet drinks are generally sweetened using artificial sweeteners.
So how are sugar-loaded drinks causing cancer?
In a mere decade, there has been a significant increase in the consumption of soft drinks and fruit juices, which has been linked to the onset of obesity in all ages. While obesity in itself has been linked to the development of a number of cancers, this is the first time that scientists have been able to show substantial evidence that these beverages could be linked directly to an increased risk of developing any form of cancer.
While the study notes that an exact cause cannot be pinpointed as it was an observational one, scientists have come up with theories for what in the drinks might be causing cancer. One theory involves the effect of the sugar on the fat stored around certain organs, such as the liver and pancreas. Another hypothesis states that the drinks affect blood sugar levels and inflammatory markers all of which are linked to an increased risk of developing cancer.
“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,” conclude researchers, adding that the results should be replicated on a larger scale for further study and confirmation.