Effects on cancer
The relationship between IS consumption and cancer in
humans was assessed in 55 scientific studies. Thirty-nine
of these studies involved the urinary tract and 32 focused
exclusively on bladder cancer. The other studies
assessed the relationship between IS consumption and
the risk of brain cancer (four studies), digestive system
cancer (six studies) or other cancers (five studies).

Except in the studies focusing on bladder cancer, the IS
in question were not identified by the authors. The relationship
between saccharine consumption and bladder
cancer was the most commonly studied, given that data
were available in rodents [70]. The results of studies in
humans are conflicting. Based on the analysis of data in
humans, it is not possible to determine a relationship
(whether for saccharine or for the other studied IS),
since the studies did not adjust their results for major
confounding factors such as exposure to chemical pollutants.
Regarding kidney, brain, digestive system and
breast cancers, the data are more limited and do not
show any relationship with IS consumption. A recent
cohort study examining the risk of lymphoma and leukaemia
suggested an increased risk of non-Hodgkin
lymphomas and multiple myelomas in males consuming
more than one serving (355 mL) per day of artificially
sweetened beverages and in the heaviest consumers of
aspartame (as a table-top sweetener and in beverages)
compared to non-consumers [71]. No significant association
was reported in women. The authors specified that
due to the differences in the results by sex, the results
should be interpreted with caution. Moreover, this study
did not take into account exposure to chemical pollutants
as a confounding factor. However, it is worth noting
that this study attempted to take into account, in its
statistical analysis, changes in the individual consumption
of artificial sweeteners over time, although little information
is available regarding the methodology.
On the whole, the epidemiological studies do not show
any effects of IS consumption on cancer risk. Only one
recent study suggested a relationship between the consumption
of beverages containing IS and the occurrence
of non-Hodgkin lymphomas and myelomas, and additional
studies are required.