The end of the ongoing debate about the safety of sweeteners does not seem near.

Many foods and drinks contain artificial sweeteners. As the name suggests, these sweeteners are added to foods instead of sugar, with the intention of making them taste equally sweet but with fewer or no calories. However, sweeteners have been the subject of debate for years. Although the European Food Safety Authority has approved 15 sweeteners and considers them safe, some scientists argue that certain approved sweeteners can be harmful and even carcinogenic.

More about sweeteners
As mentioned, sweeteners are added to sugar-free products in particular to make them a bit sweeter. You can find them, for example, in light drinks, but also in sugar-free gingerbread and sweets. Some sweeteners come from nature (a well-known example is stevia, which is extracted from the stevia plant). Others are made industrially (such as the well-known aspartame). Because sweeteners – whether they come from nature or the factory – are additives, they are often indicated with an E number. Sweeteners are only given that E number if they have been found safe by the European Food Safety Authority after thorough research.

Because millions of people ingest sweeteners every day, researchers decided in a new study — again — to examine the safety of these additives. In doing so, the team was particularly interested in whether some sweeteners could potentially increase the risk of cancer.

Study

The researchers analyzed data from 102,865 French adults who participated in the so-called ‘NutriNet-Santé program’; a research program launched in 2009 that studies the eating habits and health of Internet users. Participants voluntarily enroll and self-describe their medical histories, provide socio-demographics, and provide information about their diet, lifestyle and health.

Bandage

In the new study, the researchers first collected data on the intake of artificial sweeteners. “We looked at, among other things, acesulfame-K (E950), aspartame (E951), cyclamate (E952), saccharin (E954), sucralose (E955), steviol glycosides (E960) and aspartame-acesulfame salt (E962), summing up researchers Charlotte Debras and Mathilde Touvier from the Nutritional Epidemiology Research Team associated with French Institute of Health and Medical Research in conversation with Scientias.nl on. “Acesulfame-K (E950), aspartame (E951) and sucralose (E955) are the most consumed by the population, so it was best to study one by one.”

The team then studied which study program participants had been diagnosed with cancer after a follow-up. Statistical analyzes were then used to map out a possible link between the intake of artificial sweeteners and the risk of cancer. The team adjusted for a range of variables, including age, gender, education, physical activity, smoking, diabetes and BMI.

Increased risk of cancer

The study leads to a rather disturbing conclusion. Because participants who consumed a lot of artificial sweeteners – especially aspartame (E951) and acesulfame-K (E950) – were found to have a higher risk of developing cancer. “The results suggest an association between the intake of artificial sweeteners and an increased risk of cancer – particularly breast cancer and obesity-related cancers,” said Debras and Touvier. And that would mean that artificial sweeteners may not be safe alternatives to sugar after all.

Footnote

However, some caveats can be made about the study design and the degree of certainty of the findings. For example, the participants of the research program self-reported on their dietary intake, which means that this cannot be an entirely reliable representation of reality. In addition, most of the participants are female, have a higher level of education and often exhibit health-conscious behavior. Yet Debras and Touvier also point to the reliable side. “The study is based on a long-term program with a large sample size and follow-ups,” they say. “Each participant provides detailed information at registration and then regularly during follow-ups. In addition, accurate data is provided on health status, height, weight, physical activity, etc. Diet questionnaires have been validated through an interview with a trained dietitian and supplemented with blood and urine samples.”

According to the researchers, the findings mean that the safety of sweeteners cannot be guaranteed. “The results are robust and stable, even after repeated analyses,” said Debras and Touvier. “In addition, it is consistent with several experimental studies.”

Causality

Despite this, additional research is needed to establish a true causal relationship between sweetener intake and increased cancer risk. “Like any scientific study, this one has some limitations,” say Debras and Touvier. “At the moment, a causal relationship cannot be conclusively established on the basis of a single observational study. Also, a reverse causality cannot be ruled out. The results will therefore have to be replicated in other large-scale cohorts. Also, the underlying mechanisms will need to be elucidated by further experimental studies.”

Why?

A pressing question is why some artificial sweeteners are actually carcinogenic. “Several things are plausible,” Debras and Touvier explain when asked. “In part, the possible association could be due to overweight-related metabolic disorders. But other things can also play a role, such as inflammation, promotion of DNA damage and inhibition of apoptosis (programmed cell death, ed.). Finally, it has already been suggested that non-caloric artificial sweeteners – such as saccharin (E954), sucralose (E955) and aspartame (E951) – affect the intestinal flora. This, in turn, could play a role in the development of some cancers. But again, additional research is needed to elucidate the underlying mechanisms.”

Water

Who now plans to switch back to sugar; you better watch out for that too. It has been proven that an excessive intake of sugar is not healthy. For example, too much sugar leads to obesity, type 2 diabetes and has been linked to poorer school performance in previous studies. And so many public health authorities recommend limiting the intake of sweeteners and sugar anyway. “For example, the French government agency ANSES recommends that you avoid artificially sweetened and sugar-sweetened soft drinks and drink water instead,” Debras and Touvier quote.

All in all, the ongoing debate about the safety of artificial sweeteners doesn’t seem to end just yet. “Our findings certainly do not support the use of artificial sweeteners as safe alternatives to sugar in foods or drinks,” the researchers underlined. “The results suggest that artificial sweeteners, used in thousands of foods and drinks worldwide, may be associated with an increased risk of cancer. While this should be confirmed by other experimental studies, it provides new insights that could be important for the ongoing re-evaluation of the safety risks of sweeteners by the European Food Safety Authority and other global health authorities.”