Authors' reply.

Sir,

We would like to thank the authors[1] for the keen interest shown in our paper.[2]

(a) The authors have a query that the route of administration of aspartame and paracetamol has not been mentioned. We wish to submit that both aspartame and paracetamol were administered by the intraperitoneal route. This fact has been mentioned in Table 1, but missed a mention in the text.

(b) Regarding the issue about the carcinogenic effect of aspartame seen in doses of 20 mg/kg bw,[3] it is submitted that in our study, statistically significant antipyretic and analgesic effects were observed at low doses of 4 and 8 mg/kg bw. An 18-membered scientific panel, consisting of independent regulatory scientists and toxicologists, constituted by the European Food Safety Authority (EFSA), has concluded that the data on total malignant tumors does not provide evidence of a carcinogenic potential of aspartame.[4] These findings have been reiterated by similar studies.[56] In view of the public concerns about the toxicity of aspartame, the Scientific Committee on Food, European Commission Health and Consumer Protection Directorate-General conducted a safety review and concluded from the biochemical, clinical and behavioral research that the acceptable daily intake of 40 mg/kg/day of aspartame is entirely safe–except for in people with phenylketonuria.[7] Intakes over 1 g/day are needed to alter brain neurotransmitters and provoke seizures in monkeys, and randomized controlled trials of high doses in humans have not shown any behavioral or other effects.[89] Acute, subacute and chronic toxicity studies with aspartame, and its decomposition products, conducted in mice, rats, hamsters and dogs, have consistently found no adverse effect of aspartame with doses up to at least 4000 mg/kg bw/day.[5]

When all the research on aspartame, including evaluations in both the pre-marketing and post-marketing periods, is examined as a whole, it appears that aspartame is safe.[8-12]

However, detailed pharmacological studies for long-term safety evaluation are strongly recommended to evaluate the potential therapeutic use of aspartame.

(c) The observation that aspartame is a non-nutritive time sweetener is factually correct. The term “non” appears to have been missed out during the preparation of the manuscript, and the omission is regretted.