Aspartame -- This sweetener has been controversial since it came out and it accounts for the most complaints made to the FDA regarding side effects of its consumption. Now a new study seems to be saying that aspartame is a "multipotential carcinogen" causing dose related increase in leukaemias and lymphomas in female rats, and a dose-related increase in incidence of cancer and its precursors in the kidney (renal pelvis and ureter) as well as tumours in the peripheral nerves, in particular in cranial nerves.
Rats were studied for nearly three years, until the end of their natural lifespan; most studies last about two years. Six different dose levels were tested against a control group not given aspartame. The National Toxicology Programme of the US National Institutes of Health convened a pathology working
group to provide a second opinion on the interpretation of some of the cancerous lesions observed by the Ramazzini researchers, and helped with the statistical evaluation of data.
Aspartame is metabolised into aspartic acid, phenylalanine and methanol. Methanol is in turn metabolised to formaldehyde. Previous large-scale experiments by the Ramazzini Foundation have linked both methanol and formaldehyde to a significant increase of leukaemias and lymphomas, the researchers say. However, they point out that the other sorts of cancer they
observed in their aspartame study did not show up in studies on methanol and formaldehyde, suggesting an urgent need to study whether aspartic acid or phenylalanine were also potential carcinogens.
The researchers also found that while rats fed aspartame ate less food, there was no difference in weight between treated and untreated animals. The first results have been published in the foundation's journal, the European Journal of Oncology, and have been peer-reviewed by seven international experts, according to the journal's editorial board. The second results have not yet been peer-reviewed.
Well, that blows that theory about aspartame being great for weight loss.