"Aspartame causes brain cancer."
0phelia, I am very sorry that your mother died of brain cancer.
However, there is no evidence that aspartame causes brain cancer.
(Neither does sugar itself "cause" diabetes, but I can send you a copy of my thesis as I don't have space here for that!)
www.cancer.org/cancer/cancercauses/othercarcinogens/athome/aspartame
One early study suggested that an increased rate of brain tumors in the US during the 1980s might have been related to aspartame use. However, according to the National Cancer Institute (NCI), the increase in brain tumor rates actually began back in the early 1970s, well before aspartame was in use. And most of the increase was seen in people age 70 and older, a group that was not exposed to the highest doses of aspartame, which might also make this link less likely. Other studies have not found an increase in brain tumors related to aspartame use.
In the largest study of this issue, researchers from the NCI looked at cancer rates in more than 500,000 older adults. The study found that, compared to people who did not drink aspartame-containing beverages, those who did drink them did not have an increased risk of lymphomas, leukemias, or brain tumors.
A recent study of more than 125,000 people found a link between consumption of aspartame sweetened soda and the risk of leukemia, lymphoma, and multiple myeloma in men, but not in women. Since it also found a link between sugar sweetened soda and lymphoma in men, the researchers concluded that the links they found could be explained by chance.