This is the third article in a series of articles about the artificial sweetener aspartame. You may want to first read about how aspartame was invented and how it’s made, as well as the warning on phenylketonurics regarding aspartame.
As stated previously, aspartame is the subject of a protracted mythinformation campaign, causing many to unreasonably fear and malign this very common artificial sweetener. This article covers some of the specific health claims about aspartame.
For more information, see Aspartame and the Internet, published by The Lancet in 1999. Here are some further details of the particulars, excluding the supposed dangers of phenylalanine, which we’ve covered in the previous article.
Methanol from Aspartame?
As mentioned in the first article, aspartame breaks down into its constituent amino acids and methanol (methyl alcohol). The methanol content is approximately 10% by weight in aspartame, but it is an abundant naturally occurring compound found in the foods, including fruits, you eat, and fruit juices. Many people claim that the methanol in aspartame is converted to formaldehyde which is broken down to formic acid. The dangers from these trace amounts are greatly exaggerated. What these fear-mongers don’t tell you is that methanol is a very common breakdown product from food and drink, usually in much larger amounts.
A can of diet soda with aspartame will yield about 20mg of methanol. Compare that to 40mg from the same volume of fruit juice, except for tomato juice, which gives 4 to 5 times the amount, 120mg for the same volume. Or, how about 60 to 100mg from an alcoholic beverage?
That’s nothing. I know. Well, how about some other examples?
*One egg: 300mg of methanol
*One glass of milk: about 500mg of methanol
*A big old hamburger: 900mg of methanol
You’d have to drink a lot of diet soda to derive as much methanol as you do from these other things. And yet, even if you over-indulge, these chemicals are quickly broken down and excreted.
Methanol, when ingested, is quickly oxidized to formic acid. Formic acid can be toxic to the body in large amounts. This can occur if the production of formic acid exceeds the oxidation of formic acid. It has been estimated that the amount of methanol needed to produce these toxic amounts of formic acid is 200 to 500mg per kilogram of body weight. This is a huge amount. Let’s say you weigh only 130 pounds. You’d have to drink 240 to 600 liters of aspartame-sweetened drinks at one time. Notice I stressed the at one timepart. The methanol is continually oxidized to formic acid and the formic acid is continually oxidized, in very short order. If you stagger your consumption, the danger from formic acid toxicity is removed. This is not to suggest that you should drink such ridiculous amounts of diet drinks, of course. I am only illustrating the point. The equivalent of 24 liters of aspartame flavored drink for a 130lb person has been administered to individuals and there was nowhere near enough peak methanol concentration in the blood to be toxic. What’s more, there was no detectable change in blood formic acid amount.
There has been no evidence of toxic effects found from the consumption of the equivalent of 17 cans of diet soda a day, for a 70kg adult. What’s more, there is no increase in plasma concentrations of methanol, formic acid, or phenylalanine.
The results in infants receiving 100mg/kg aspartame resulted in peak blood methanol concentrations similar to those in adults, which suggest a similar rate of clearance.
Longer term tolerance studies of up to 27 weeks showed no evidence of methanol toxicity as measured by changes in ophthalmologic status or changes related to methanol toxicity.
The dose of methanol from aspartame is very tiny. Hell, the seemingly huge doses from these other foods are easily handled by the body, let alone the small amount from aspartame.
Aspartame Causes Many Disease and Conditions
Aspartame has been claimed to cause many diseases and health conditions. Multiple Sclerosis, lupus, Parkinsons, diabetes mellitus, Alzheimer’s Disease, brain tumors. Coma! Vertigo, dizziness.
There is nothing to any of these claims. They are, in fact, quite ludicrous. The cancer claims, which of course, came from dosing rats with ridiculous amounts of the stuff, are silly, as well. The myth about cancer is not unique to aspartame. Artificial sweeteners, in general, are always being claimed to cause cancer yet none have been shown to. Even the cancer danger of saccharin has been overturned and saccharin-containing products no longer need to carry a warning. The American Dietetic Association and the National Cancer Institute, and the American Cancer Society all concur that there is no correlation between artificial sweeteners and cancer.
I understand, of course, that you may be under the sway of a conspiracy theorist health guru who tells you that they all lie! Oh, well.
Aspartame and Seizures
The only common concern that may have a grain of truth is the claim that aspartame causes seizures. But this is not because it causes seizures out of the blue but that it can raise the threshold for seizures in those with epilepsy.
Since aspartame is chemically related to the excitatory amino acids glutamine and aspartate, and since these aminos, in large amounts, can cause seizures and neurotoxic changes, the concern has been raised that aspartame can cause seizures in those with epilepsy. However, there has been no evidence that aspartame causes seizures or neurotoxic effects when consumed in recommended (read reasonable) amounts. Also, it has been speculated that aspartame could increase phenylalanine concentrations in the brain and therefore cause a deficiency of monoamine neurotransmitters, thus increasing seizure susceptibility. This has not been found to be true. Reports claiming that aspartame caused seizures are anecdotal and there is no evidence that aspartame actually caused any seizures.
The only study to show a potentially significant alteration in neurophysiological parameters was done on children with primary absence epilepsy (sometimes called petit mal seizures), with several hours of EEG monitoring. 1 In a double-blind crossover design, 40mg aspartame was used one day and a sucrose-sweetened drink the next, as a placebo control. Children were found to spend more time in a 3-HZ spike-wave EEG pattern than in the placebo control. The actual amount of time was not given. Furthermore, diet was not controlled for and the choice of sucrose as a control is not without problems, as sucrose may have a positive effect on this type of EEG abnormality so that the placebo could have been more like an actual treatment. 2
Despite the lack of credible evidence, aspartame is often included in the scare books and articles about the oh so dangerous EXCITOTOXINS, along with MSG, another big bad boogeyman.
Aspartame Paradoxically Increases Appetite
There is no credible evidence that aspartame increases energy intake, changes the distribution of macronutrient intake in the diet, or results in an increase in subjective feelings of hunger. Aspartame seems to have no different effect on hunger and satiety than sugar, except that it results in a significant decrease in caloric intake. For further reading see the sources below.
Now let’s look at some of the negative studies concerning aspartame. We have “effects on patients in a vulnerable population, headaches, etc.
Aspartame Effects on Depressed Patients
This study, called “Adverse reactions to aspartame: double-blind challenge in patients from a vulnerable population” was written by Ralph G. Walton, et al. Although the study authors recruited 40 people with unipolar disorders and a similar number of people without any history of depression. They claim the study was halted after only 13 patients completed the study because of the severity of reactions within the group with a history of depression. Only 11 of those 13 reported on actually finished taking all their capsules. Even though the study was never complete and the number of participants was exceedingly low, the reported the results anyway because they thought they were significant.
In the end, they were left with data from 13 people. Eight of them were from the group with depression history and 5 were non-patient volunteers. Five of the depressed group were on anti-depressant drugs. Before the study began, they had a 3-day washout period..no aspartame.
Then the study was done in two seven day periods, between which there was another 3-day no-aspartame period. The aspartame was given in pills and an identical looking placebo was used. The group was randomly divided to receive the equivalent of 30mg/kg aspartame a day, so to be equal to about 10-12 cans of diet soda a day for a 70kg person. The patients self-reported based on the occurrence of a number of symptoms, including headache, nervousness, dizziness, trouble remembering, etc.
Here is where it gets interesting and when we can see that even psychiatric scientists can become hysterical along with their patients. The abstract of the study makes it seem as if lots of patients were being so badly affected by the aspartame that the board had no choice but to pull the plug, in order to protect the participants from further unreasonable danger. But this was not actually the case. There were three patients who felt they were being “poisoned,” presumably while on aspartame, although they had no way of knowing. One was one female participant, with a history of depression, who felt as if she was being poisoned while on aspartame and thought she should withdraw from the study.
There was an older PhD psychologist male with a history of recurrent major depression, who suffered a detached retina and had to be rushed to the hospital. Interestingly, he did not cease taking his capsules until into his second week on the PLACEBO.
Another patient who had felt “poisoned” got a conjunctival hemorrhage, apparently while on aspartame, although the language of the study is confusing.
It was these two ophthalmologic events, one of which occurred during the aspartame arm and one of which occurred during the placebo arm, which caused the plug to be pulled. To imply that a host of serious complications occurred in the aspartame arm which caused the study to be stopped is stretching it a bit and seems to be designed to get us to ignore that fact that the study was never completed.
In all, two persons withdrew from the study. Even though they did not complete all the symptom reporting, they were still included in the study. Each having 3-day periods of symptom reporting. In the end, only 11 patients completed the entire study and reported symptoms for the entire 14 day period. Why is this important? Because even though the study authors had sought data from a number of people apparently close to 80, they willingly used data from ONLY 11. The two that withdrew early should NOT have been included. They thought that the negative results of 8 of those patients was “significant” because, you know, it’s 8 out of 13 (but really 11). However, you cannot throw out most of the data and then assign significance to the small amount left just because you think it seems more than chance would allow. This is a misunderstanding of statistical analyses. We will never know if the data would have evened out more, as you would expect if all the participants had been allowed to complete and report their results. So, what it comes down to is that someone got afraid of being sued because some people happened to have some medical emergencies and got some persons with a history of depression got a bit hysterical while taking a mysterious pill. There is just not enough data to conclude that the aspartame had any real affect. The study was never completed. Keep in mind that the authors admitted that most reports of behavioral or cognitive reactions to aspartame had been completely anecdotal and made the disingenuous leap to other studies that failed to replicate those (anecdotal) results had been criticized on methodological grounds and/or because of funding from the Nutrasweet company. In other words, discounting their own lapse in methodology. They further went on to say that they felt that the problem was that earlier studies had not used a “vulnerable population.”
The two actual physical events cannot be traced to the aspartame. Besides these two events, the symptom checklist relied on entirely subjective reporting of symptoms from a ‘vulnerable’ population. Let’s look at it further, though, because it is interesting to behold.
Of the patients with depression, 63% experienced headache on placebo while 88% experienced headache on aspartame. Of the non-depressed volunteers, 88% had headache on placebo and 20% on aspartame. Curious. Apparently, the fact that the authors paid so much attention to data from “vulnerable” volunteers, they ignored the data from “non-vulnerable” volunteers. Makes you wonder why they included any at all. All I can get from this is “headaches happen” and I do not doubt at all that the data would not have been so significant on the vulnerable side had all the study been completed. The chart given in the study, however, does not mention the severity (as reported) of the headaches.
But wait. The percentages make it sound oh so significant, don’t they? Well, 63% of the depressed patients was a total of 5 and 88% was a total of 7. So, 5 people versus 7 people. Big whoop. On the other hand, 4 non-depressed people got headache on placebo and one on aspartame. Again, big whoop. I won’t bore you with every symptom. Let’s just pick one more.
Of the patients with depression, 13% got dizzy while on placebo. That is, um, one person. 25% got dizzy on aspartame. That is two persons. Oh my, it was an epidemic of dizziness! I mean, there is no way that two people could experience dizziness by chance! I never ever get dizzy unless I ingest poison. Oh, wait, I do.
Now, of the non-depressed volunteers, 40% got dizzy on placebo. That is two persons. And 0% got dizzy on aspartame. So, of course, you can see, that aspartame has the opposite effect on non-depressed volunteers. It cures dizziness for them. Yep.
If it seems I am doing a hatchet job, well, the study is quite silly once you see the actual numbers involved. It is hard not to find it amusing. Many unrelated symptoms were reported, such as headache, dizziness, binge eating, nervousness, feeling blue or depressed, nausea or upset stomach, bad taste in mouth, uncontrollable temper outburst, fatigue, malaise, swollen lips, facial numbness, irritability, and more. Notice that some of these symptoms overlap if you evaluate them subjectively. Yet, for instance, negative thoughts, temper outburst, and irritability counted as separate symptoms. If you are irritable, you might have negative thoughts. If you are irritable and having negative thoughts, you might have an outburst. Any of these symptoms, and the number who reported them, taken alone, would be meaningless. But the authors lumped them all together and what’s more, any symptoms reported as mild or above, was included, even if it was only reported on ONE DAY of the 7 day period. The fact that any one person had any one of these symptoms at any one time, means nothing. But if you choose to lump all the symptoms together as data, suddenly you have an epidemic. Again, should more data have been collected, these trends might have continued, or they may have evened out as the number of people completing the study increased. 3
Now, I can’t leave this study behind without a mention of the oh so famous P-value. You see, the researchers undoubtedly got all excited about their P value of 0.01. Hey, that’s better than the magical 5% threshold! I don’t pretend to understand all the math involved in calculating P values, or in interpreting them, but I can almost guarantee that the study authors, as well, do not understand them. Perhaps they thought this meant the null hypothesis had only a one percent chance of being true. Which is not true. There are so many problems with P-value and its interpretation but as often happens, the authors found that a “statistically significant” finding must be clinically important. However, as I mentioned earlier, the magnitude of the effect was not even considered, and just what the “effect” was is hardly outlined in the study as so many different symptoms were mish-mashed together. So, the take home points:
- Only 11 completed the study.
- The authors reported a statistically significant result, but to obtain this result, symptom complaints across a large range of unrelated categories were included and consolidated together.
- Furthermore, two patients who had withdrawn from the study for adverse events had their data re-entered into the study.
The errors are so broad and vast that there is no point in considering this study to be of any use whatsoever.
So Many Products Contain Aspartame, Isn’t This a Problem?
In previous articles on aspartame, I have focused on diet beverages, especially sodas, containing aspartame. Soda has its own negative campaign and aspartame is one of the “ingredients” of this campaign, along with high fructose corn syrup, caramel coloring, and other components. Therefore, it made sense to me to mention diet drinks, and it is fair to say that diet drinks represent by far the largest source of aspartame in the diet. This artificial sweetener is, however, used hundreds of different types of food products. With such widespread use, should we be concerned? It is a fair question, I think. As we’ve seen, it would be very difficult to ingest enough aspartame from diet drinks to represent any danger to our health.
Acceptable Daily Intake (ADI) Of Aspartame
Still, there are thousands of products that contain aspartame. First, let’s clear up some common confusion concerning the ADI (Acceptable Daily Intake). This amount is supposed to represent what you can safely take in day after day for a lifetime. It is not about what you can take in on a given day. In other words, just because you consume an amount larger than the ADI for aspartame (or anything else), on one day, does not mean you are going to drop dead. To put the ADI further into perspective, consider that, in terms of sweetness, 5omg/kg of aspartame is like a 60kg person consuming 1.3lbs (600 grams) of sugar (sucrose) in a day.
If your diet has a large proportion of aspartame-containing “diet foods” you are still probably not in much danger, but it would be wise to reevaluate such a diet because it is obviously not a balanced and healthy one. A large proportion of such products would also mean a small proportion of fresh vegetables, fruits, fish, and lean meats.
Aspartame Kills Ants?
No. This myth is related to another myth: that aspartame was originally being developed as an ant poison and then it was realized that more money could be made from exploiting its sweet taste as an artificial sweetener. Apparently, most of this myth stems from an article spoof (a parody) about some guy claiming that he used aspartame to kill ants in his house. As is no unusual, it has been taken as truth. Read the Snopes article
In-depth Reading on Aspartame
If you want to get down and dirty about aspartame in a book check out The Clinical Evaluation of a Food Additive: Assessment of Aspartame. You can get it used for a very low price since the many scare books from the popular press easily outsell such a comprehensive and scholarly text. Maybe you’d rather believe all the pseudoscience crap, though, as it is nice to think that if we can simply avoid some poisons we can avoid disease or other health conditions and live forever.
The final article in this series on aspartame concerns the potential source of all the misinformation on aspartame, a famous ‘article’ which became a chain email beginning in the late 1990’s.
- Camfield, P. R., Et Al. “Aspartame Exacerbates EEG Spike-wave Discharge in Children with Generalized Absence Epilepsy: A Double-blind Controlled Study.” Neurology 42.5 (1992): 1000-3.
- Tschanz, Christian. The Clinical Evaluation of a Food Additive: Assessment of Aspartame. Boca Raton: CRC, 1996.
- Walton, Ralph G., Et Al. “Adverse Reactions to Aspartame: Double-blind Challenge in Patients from a Vulnerable Population.” Biological Psychiatry 34 (1993): 13-17.