Aspartame and its effects on health
BMJ 2004; 329 doi: https://doi.org/10.1136/bmj.329.7469.755 (Published 30 September 2004) Cite this as: BMJ 2004;329:755All rapid responses
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RE: Aspartame and its effects on health
Thank you for bringing the aspartame issue to the attention of your
readers. Nonetheless, the proper respect and recognition for the consumers
who have suffered medically documented illnesses from aspartame, for the
research scientists at universities in both the U.S. and the U.K. who have
documented the damaging effects of aspartame, and for the mothers of
children born with mental and physical deformities caused by aspartame
during pregnancy – well, they were not properly mentioned in your article.
Yes, aspartame dangers are real and scientifically supported beyond
any reasonable doubt. I provide scientific references and data in my book
on aspartame dangers (Sweet Poison, New Horizon Press) citing scientific
documentation that aspartame, indeed, causes holes in the brains of
laboratory mice, mammary gland tumors and testicular tumors in rats, fetal
deformities, and behavioral disorders. Dr. Russell Blaylock, M.D. is
currently connecting aspartame to Multiple Sclerosis. The U.S. government
agencies you cite in your article are clearly documented as “denying”
aspartame approval TWICE before its “questionable” sanction in 1981.
Since aspartame came on the market over twenty years ago, many
diseases such as MS, ALS, Parkinson’s, Alzheimer’s, depression,
aggression, and, now, obesity have become epidemic. The answer to these
concerns is not more “toxic brain chemical” use as you suggest, but
exactly the opposite - the answer is more public "caution" concerning the
neuro-excitotoxins in aspartame and their damaging effects to the brain.
Obesity among British and American children is horrifying and will only
worsen if eating chemical foods and drinking non-nutritive colas is
encouraged.
Before you publish your next article discrediting the many brilliant
research scientists, doctors, and responsible consumers informing people
of the dangers of aspartame and other chemical sweeteners – please, do
more thorough research.
Competing interests:
None declared
Competing interests: No competing interests
I was surprised by much of the content of Professor Lean and
Catherine Hankey’s editorial on the effects of aspartame and health (1).
It starts with an incomplete description of aspartame’s components:
aspartame is not only composed of two amino acids (phenylalanine and
aspartic acid) but methanol also. This is crucially important as methanol
has toxic potential and may also be converted to formaldehyde within the
body (2). It has been demonstrated in animals that low level ingestion of
aspartame can lead to formaldehyde accumulation in the various parts of
the body including the liver and brain (3). In addition, several human
studies have found that chronic, low-level formaldehyde exposure has been
linked with a variety of health issues including headaches (4,5,6),
fatigue (4,5), chest tightness (4), dizziness, nausea and lack of
concentration (6), seizures and neurobehavioural impairment (7). Long-
term studies into the effects of ingestion of aspartame or its components
in humans have not been done. Until they are, it seems premature to
conclude that aspartame is safe.
Aspartame’s manufacturers and scientific advisors often defend
aspartame by stating that it brings nothing new to the diet, as all of its
constituents (including methanol) are found naturally in the diet. This
defence is flawed in that it presupposes that naturally occurring food
constituents can have no adverse effect on health. Also, it is possible
that when found naturally in food (such as bananas and tomatoes), methanol
may be ingested with other food elements that might protect against
toxicity. While this notion may seem far-fetched to some, an example of
it is known in the real World: two studies suggest that giving beta-
carotene in supplement form may increase risk of lung cancer in smokers,
although there appears to be no such association with dietary beta-
carotene.
While the European Scientific Committee Food’s 2002 report appears to
exonerate aspartame, the Committee seems to have be ignorant of, ignored,
or dismissed studies which show aspartame might have adverse effects on
health. Such research includes an animal study in which aspartame
disrupted brain chemistry (8). Also, in humans, aspartame was found to
induce neurophysiological changes that might increase seizure risk (9).
In addition, at least one study has linked aspartame use with depression
in individuals susceptible to mood disorder (10). Other studies have
linked aspartame ingestion with headaches (11,12). Other studies that
attest to aspartame’s potential for harm can be found in an on-line review
(13).
This review is particularly disconcerting as it shows a disparity in
the findings of safety studies which appears to be related to source of
study funding. In this review, studies in peer-reviewed medical or
scientific journals were assessed for funding source and study outcome.
Of 166 studies, 74 had at least partial industry-related funding and 92
were independently-funded. While 100 per cent of industry-funded studies
conclude aspartame is safe, 92 per cent of independently funded research
identified aspartame as a potential cause of adverse effects.
Professor Lean and Ms Hankey speculate on the potential weight loss
benefits of aspartame. Their assessment is largely theoretical based on
the potential for the replacement of sugar with aspartame to bring about
caloric deficit. They acknowledge that the evidence for the weight loss
effects of aspartame is inconclusive. However, they fail to mention
studies which have shown that aspartame ingestion may actually lead to
increased food/calorie intake (14,15). The case for the benefits of
aspartame use for weight loss seems to rest on one relatively short-term,
unblinded clinical study in obese women (16). Men, children and
individuals with less extreme weight problems (all groups of individuals
who might be using aspartame for the purposes of weight loss) were not
included in the study.
It is somewhat concerning that, to date, not one single double-blind
placebo-controlled study designed to assess the effects of aspartame on
weight has been published. I’m left wondering why there is such
enthusiasm from some quarters of the nutritional establishment for
aspartame in the diet, bearing in mind the singular lack of evidence that
it is efficacious for the purposes of weight loss.
It seems that the health-related benefits of aspartame are simply
unproven, and that evidence exists which suggests that this novel chemical
does have real potential for harm. The glaring disparity in results
between industry-funded and independently-funded research is clearly of
concern. Professor Lean and Ms Hankey conclude their editorial by
suggesting that the public probably needs protection from misleading
websites. However, by the same token, the public and members of the
medical profession should probably be protected from misleading editorials
too.
1. Michael Lean, Catherine Hankey. Aspartame and its effects on
health BMJ 2004;329:755-756 (2nd October 2004).
2. Kavet R, et al. The Toxicity of Inhaled Methanol Vapors. Critical
Reviews in Toxicology 1990 21;1:21-50
3. Trocho C, et al. Formaldehyde Derived From Dietary Aspartame Binds
to Tissue Components in vivo. Life Sciences 1998 63;5:337
4. Main DM, et al. Health Effects of Low-Level Exposure to
Formaldehyde. Journal of Occupational Medicine 1983 25;896-900
5. Olsen JH, et al. Formaldehyde induced symptoms in day care
centers. American Industrial Hygeine Association Journal 43;5 366-370
6. Burdach S, et al. Damages to health in schools. Complaints caused
by the use of formaldehyde-emitting materials in school buildings.
Fortschritte Med 1980 98 11; 379-384
7. Kilburn KH, et al. Neurobehavioral and respiratory symptoms of
formaldehyde and xylene exposure in histology
technicians. Arch Env Health 1985 40; 4; 229-233
8. Sharma RP, Coulombe RestioA Jr. Effects of repeated doses of
aspartame on serotonin and its metabolite in various regions of the mouse
brain. Food Chem Toxicol. 1987;25(8):565-568
9. Camfield, PR, et al., Aspartame exacerbates EEG spike-wave
discharge in children with generalized absence epilepsy: a double-blind
controlled study. Neurology, 1992;42:1000-1003
10. Walton RG, et al,. Adverse reactions to aspartame: double-blind
challenge in patients from a vulnerable population. Biol Psychiatry.
1993;34(1-2):13-17.
11. Van Den Eeden SK, et al. Aspartame Ingestion and Headaches: A
Randomized, Crossover Trial. Neurology. 1994;44:1787- 1793
12. Lipton RB, et al. Aspartame as a dietary trigger of headache.
Headache. 1989;29(2):90-92
13. http://www.dorway.com/peerrev.html
14. Lavin JH, et al. The Effect of Sucrose- and Aspartame-Sweetened
Drinks on Energy Intake, Hunger and Food Choice of Female, Moderately
Restrained Eaters Int J Obes. 1997 21:37-42
15. Tordoff MG, Alleva AM. Oral stimulation with aspartame increases
hunger. Physiol Behav 1990 47:555–559
16. Blackburn GL, et al. The effect of aspartame as part of a
multidisciplinary weight-control program on short- and long-term control
of body weight. Am J Clin Nutr. 1997 65(2):409-418.
Competing interests:
None declared
Competing interests: No competing interests
Your editorial fails to address the reasons why aspartame has been “demonized”. Since at least 2/3 of adults currently consume aspartame this is a serious issue.
Although aspartame contains two amino acids it is not a natural substance. It was originally developed as a drug to treat peptic ulcers. We were not designed to be exposed to large amounts of isolated free form amino acids. Free form aspartic acid is a damaging neuro excitotoxin mediated through NMDA receptors (1).
While it is true that phenylalanine is an essential amino acid it is rarely consumed in nature as a free from amino acid or in large doses. In 1987 it was calculated that nearly 4 million kg of phenylalanine were introduced annually into the food supply as aspartame. The consequences of flooding the brain with phenylalanine are profound as it serves as a precursor for two major neurotransmitters, dopamine and norepinephrine. The altered amino acid ratios can modify tryptophan concentrations and secondarily serotonin levels. This can lead to seizures, confusion, erratic behaviors, depression and other neuropsychiatric disturbances.
Interestingly, the FDA regards adverse reactions like seizures to products containing aspartame as only anecdotal idiosyncrasies that do not have to be reported because of aspartame’s Generally Recognized as Safe classification.
The methyl ester joining aspartic acid and phenylalanine is metabolized to a two potent neurotoxins methanol and formaldehyde. This is not insignificant as the digestion of aspartame yields 10% methanol by weight.
Additionally, the vast majority of the flawed “scientific” studies used to support the safety of aspartame products were funded by the manufacturer. The shortcomings variously pertain to the materials used, the amounts of administration, the nature of control subjects, the duration of such studies, the contents of presumed placebos and the arbitrary interpretation of results.
Obrenovitch TP Adv Exp Med Biol. 2003;527:147-54.
Competing interests:
None declared
Competing interests: No competing interests
Re: Aspartame and its effects on health
BMJ 2004; 329: 755-756 by Lean and Hankey
Lean and Hankey state what so many assume, wrongly - that fluoride
deficiency leads to tooth decay.
"...it must be acknowledged that a lack of fluoride does not cause
dental caries," according to "Effective use of fluorides for the
prevention of dental caries in the 21st century: the WHO approach," in
Community Dentistry and Oral Epidemiology (2004;32:319-21).
The United States Centers for Disease Control says that fluoride's
non-adverse effects occur topically after teeth erupt and that “The
prevalence of dental caries in a population is not inversely related to
the concentration of fluoride in enamel, and a higher concentration of
enamel fluoride is not necessarily more efficacious in preventing dental
caries.” (1)
Fluoride is not an essential nutrient. Optimal dosage is based on
belief.(2)
References:
1) Recommendations for Using Fluoride to Prevent and Control Dental
Caries in the United States, August 2001,
http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5014a1.htm
2) National Research Council (1993). Health Effects of Ingested
Fluoride. National Academy Press, Washington DC. See page 30
http://books.nap.edu/books/030904975X/html/30.html
Competing interests:
None declared
Competing interests: No competing interests
Aspartame - balanced and impartial editorials please
I would like to ask why the editorial on aspartame went to such
lengths to vindicate the substance without any balanced review of the
numerous papers on its side effects. An editorial should impartially
review all aspects of the current information on a subject and leave it to
the reader to decide or research further. In fact the excellent rapid
responses by Mercola, Biffra and Hull clearly state the other side of the
coin. I am particularly concerned because of personal experience having
had a severe episode of fortification spectra after trying aspartame
sweeteners - the like of which I have never had in 37 years of being a
migraine sufferer. What could the effect be in those with significant
cerebrovascular disease? This substance was approved by the FDA in 1981
because of political armbending for industrial reasons - not because of
safety. I would like to see another editorial to balance the one by Lean
& Hankey as too many reports of adverse effects exist for this to be
dismissed as hypochondriasis or peoples' resentment of food interference.
Competing interests:
None declared
Competing interests: No competing interests