Here, Dr Briffa gives his personal opinion on aspartame:
“The companies that make it and ‘expert panels’ conclude it is safe. Yet, anecdotal reports on the web and elsewhere about that claim aspartame has the capacity to damage human health and cause symptoms that range from headaches and seizures and multiple-sclerosis type symptoms and depression.”
Anecdotal reports on the web make all sorts of claims. Are we elevating anecdote above evidence now Dr Briffa? There isn’t even a link in Briffa’s blog to these anecdotal claims (google brings up 200k results for ‘dangers of aspartame’ [googling], although one of these is snopes – myths are available for your delectation here) . He does provide references, but most of these seem to relate to the dangers of formaldehyde rather than aspartame itself.
“Once in the digestive tract, the body can digest aspartame down to its two amino acids, and the methyl groups ends up being spliced off to form something called methanol. This is crucially important as methanol (the prime constituent in methylated spirits) has toxic potential and may also be converted to formaldehyde (used for preserving dead bodies) within the body.” So Briffa seems to be saying that it is the methanol that is dangerous. I used the Quackometer (http://www.quackometer.net/) QuackSafe Web Search Engine to look for information on methanol in fruit and found this: According to a letter to the Lancet quoted on Junk Science, “Although a 330 mL can of aspartame-sweetened soft drink will yield about 20 mg methanol, an equivalent volume of fruit juice produces 40 mg methanol, and an alcoholic beverage about 60-100 mg” and they make the point that “the amount of phenylalanine or methanol ingested from consumption of aspartame is trivial, compared with other dietary sources.” ACSH have a pdf available on sweeteners that includes the following: “Fruit juices contain substantial amounts of methanol; for example, apple juice has been reported to contain up to 88 milligrams per liter. This is not a reason to avoid apple juice, however. To obtain a fatal dose of methanol from apple juice, an individual would have to consume between 100 and 1000 quarts of the juice at a single sitting – an obviously absurd scenario.” ACSH. Skeptics dot com in Australia (Skeptics) write that “Volume for volume, tomato juice produces six times more methanol than does diet cola. I don’t get emails about the dangers of tomato juice.” I do hope that the Dr Briffa hasn’t fallen into the trap of “natural good, synthetic bad”.
Brilliantly, the first google ad on Briffa’s aspartame post is for http://www.aspartame.info/, who link to reported concerns of the New Zealand Food Safety Authority (NZFSA) relating to “anecdotal claims made by anti-aspartame campaigners about the sweetener [that] do not seem to be supported by actual evidence” as well as linking to the study Briffa is criticising and they also have a scientific library which includes an abstract of a study relating to methanol from aspartame and the formation of formate: ” Methanol concentrations were below the level of detection (0.4 mg/dl) in the blood of the 12 normal subjects who ingested aspartame at 34 mg/kg.” and “Blood formate analyses were carried out in the 6 subjects who ingested aspartame at 200 mg/kg, since recent studies indicate that the toxic effects of methanol are due to formate accumulation. No significant increase in blood formate concentrations over predosing concentrations was noted.” come from J Toxicol Environ Health. 1981 Feb;7(2):281-90. Blood methanol concentrations in normal adult subjects administered abuse doses of aspartame Stegink LD, Brummel MC, McMartin K, Martin-Amat G, Filer LJ Jr, Baker GL, Tephly TR. Here on the pro-aspartame website: methanol concentrations.