Title: Alternative Sweeteners

Aspartame 49
day for 60-kg adults (64). Thus, acceptable dietary exposures to methanol are
approximately 25 times potential exposures to methanol after 90th percentile consumption
of aspartame.
Recently, Trocho et al. (65) concluded from a study in rats that aspartame
may be hazardous because formaldehyde adducts in tissue proteins and nucleic
acids from aspartame may accumulate. However, according to Tephly (66), the
doses of aspartame used in the study do not even yield blood methanol concentrations
outside control values. Furthermore, the amounts of aspartame equal to that
in about 75 cans of beverage as a single bolus result in no detectable increase
in blood formate concentrations in humans, whereas increased urinary formate
excretion shows that the body is easily able to handle even excessive amounts
of aspartame. In addition, there is no accumulation of blood or urinary methanol
or formate with long-term exposure to aspartame. Thus, Tephly concluded that
‘‘the normal flux of one-carbon moieties whether derived from pectin, aspartame,
or fruit juices is a physiologic phenomenon and not a toxic event’’ (66).
D. Postmarketing Surveillance of
Anecdotal Health Reports
Aspartame has been the subject of extensive postmarketing surveillance. Shortly
after its widespread marketing, a number of anecdotal reports of health effects
appeared which some consumers related to their consumption of aspartamecontaining
products. Not unexpectedly, negative media stories influenced the
numbers and types of these reports. The NutraSweet Company took the unprecedented
step of instituting a postmarketing surveillance system to document and
evaluate these anecdotal reports (24, 25, 67). Data from this system were evaluated
by the company and also shared with the US FDA, as discussed later.
After the approval of aspartame in carbonated beverages in 1983, an increase
in the reporting of adverse health events allegedly associated with the
consumption of aspartame-containing products led the FDA to request the Centers
for Disease Control and Prevention (CDC) to evaluate these reports (68, 69).
The CDC was charged with describing the types of complaints and determining
whether there were any specific clusters or types of complaints that would indicate
the need for further study. The CDC concluded, ‘‘Despite great variety overall,
the majority of frequently reported symptoms were mild and are symptoms
that are common in the general populace’’ (68). The CDC could not identify any
specific group of symptoms that was clearly related to aspartame but believed
that focused clinical studies would be the best mechanism to address the issues
raised by these reports.
In the mid-1980s, the FDA Center for Food Safety and Applied Nutrition
(CFSAN) established its own passive surveillance system, the Adverse Reaction
Monitoring System (ARMS), to monitor and evaluate anecdotal reports of ad-