There has been great debate amongst experts in the field of diet and nutrition over the last fifteen to twenty years regarding the safety of artificial sweeteners, primarily aspartame. Often times, certain influential public figures (with no dietary credentials whatsoever might I add) receive extraordinary exposure from the media on this subject, thus resulting in the skewed opinion and misrepresentation toward the public. Reporters capture this, and mislead the public and my job here is to inform you, not that sugar substitutes are good for you, but how they are all right in moderation and that if you drink a diet soda in the morning, you are not going to suddenly develop a cancerous tumor from it, rest assured.
One thing to keep in mind if you have the rare (1 in 15,000) genetic disorder phenylketonuria, this entire article holds no weight, you must prescribe to a diet low in phenylalanine, which means no aspartame for you.
ASPARTAME IS ONLY IN DIET SODA
The title is a tad misleading. Diet soda gets the most scrutiny but one thing needs to be made clear. Whether you want to believe it or not, it’s in a host of items you would not expect; from sodas to tomato juice, from Jell-O to the little packets you see at the coffee shop in town. In fact, an 8 ounce glass of tomato juice has six times the amount of aspartame that a can of Diet Coke has. The average American consumes about 5 milligrams per kilogram of bodyweight, so for a 200 pound person, that is roughly 455 milligrams of aspartame, per day. Here we sit in the year 2016 and the companies using this specific sweetener are beginning to see a decline in sales, so many of them are switching to another source, namely sucralose and acesulfame potassium. The main reason for this shift is due to supply and demand, more people are looking for a product that is not aspartame based. But my question to you is, why?
The view on aspartame has changed drastically over the past decade thanks to the various sources which “planted the bug in our ears,” the most critical would likely be the report on “60 Minutes” back in the late 90’s, when they combated the approval of aspartame by the FDA. Others include one of the most popular movies of 2004, “Mean Girls”, the man with all the answers “Dr. Oz” and even the conspiracy theorists that got their five seconds of fame. This sparked the “health cult,” that demonizes anything that isn’t “natural,” organic, non-GMO, or vegan. The media portrays “science” unfairly and there is a combating argument for the efficacy of artificial sweeteners, one cannot simply believe everything seen on the internet or television.
The Food and Drug Administration is responsible for ensuring the safety of consumers by checking and re-checking ingredients used in foods, as well as cosmetics and medical equipment, ect. Since aspartame was brought before the FDA in 1974, it passed all FDA criterion, including safety and efficacy to name a few. Time and time again, it is challenged only to have the same outcome, even to this day. Here in the United States, the acceptable daily allowance sits around the 50 milligrams per kilogram of body weight mark. Based on information from Cancer.Org, the FDA sets the ADI for about one hundredth of the dose to begin causing any health concerns. Let’s take a deeper look into the biological and mechanistic actions behind aspartame and dive into some research to really pinpoint on whether or not this compound can be deemed safe for human consumption. The most common theme when people discuss the negative impacts of diet soda, (particularly since it is the most common item with this sweetener in it) is the idea that is causes cancer, recall Mean Girls.
ASPARTAME AND FORMALDEHYDE, MECHANISTIC ACTION
The first concept that needs to be addressed surrounding aspartame is impact it has on our body and our body’s cells. Aspartame is a dipeptide, organic compound formed by two amino acids; aspartic acid and phenylalanine. The impact that is had on the body relates to the breakdown process, essentially splitting into said amino acids and methanol.
Methanol is what critics are fast to jump on, as methanol converts to formaldehyde in the body through the action of a liver enzyme known as alcohol dehydrogenase. Formaldehyde is then brought up for debate as this is a substance that is accepted as carcinogenic, and much research has been provided as of late associating it with several types of cancer including; nasal sinus cancer, nasopharyngeal cancer, and some forms of leukemia. It is posed that formaldehyde is not the main issue, but formic acid is, which is looked will be explained shortly.
The main point is that these studies conducted show that there is a correlation between the exposure of a high concentration of formaldehyde over prolonged durations and the incidence of cancer. The subjects used in these studies were all workers “in an occupational setting that used or made formaldehyde,” like industrial workers, embalmers, or even construction crews in some cases . Formaldehyde is also considered to be mutagenic and corrosive in high amounts, and when contact occurs in the concentration of 30 parts per million, it can cause contact dermatitis . When inhaled at one tenth the concentration, one can expect slight, acute sensory irritation. Keep in mind that there is an enormous difference in dermal contact, inhalation, and oral consumption. The latter under most circumstances is likely to have less of an impact in comparison to the other two, based on concentration alone. Let’s begin with providing a few “healthy” dietary sources that provide formaldehyde: fruits like strawberries and apples, coffee, fish, and vegetables. What a lot of people don’t look into is that formaldehyde is produced within the body each and every day as a result of cellular metabolism, in amounts thousands of times higher than a can of diet soda. Also, when looking at the toxicology of formaldehyde, one can see that it’s actually used to form the nucleotide bases of our DNA as well as amino acids. When excess is ingested or produced, it is however, easy for the body to break down, which is where this cancer argument begins to fall apart. Formaldehyde is converted to formic acid in the body, almost immediately. Once formic acid enters the gastrointestinal tract, it is excreted out. The second method of removal is by degraded by carbon dioxide and water, which are both prevalent in our bloodstream . According to statistics from Cancer.Org regarding the inhalation of this substance, even prolonged exposure at 1.9 parts per million for 40 minutes provided no change in plasma concentrations of formaldehyde . So by knowing that our body possesses the ability to metabolize this compound when in sane amounts, even when inhaled, there is not much basis for discussion after that point. To relate this to aspartame, concentrations need to be looked at. As stated by the FDA, “The calculated level of formaldehyde exposure is approximately 61.3 mg (milligrams) for every liter of aspartame ingested. That is over twice the level necessary to cause irreversible genetic damage in humans and several times the level shown to cause chronic neurological, cardiovascular, musculoskeletal, and other symptoms in long-term industrial exposure research. “That would equate out to 1,000 grams of aspartame, in one single sitting to produce adverse effects. Mind you, one can of diet soda provides a mere 180 milligrams. But surely there has to be some incidence of cancer in rats, the media had studies!
CANCER PROVEN FROM ASPARTAME
Arguably the most spoken of talk point of many anti-aspartame zealots are the experiments done on rats. *The link: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1392232/ provides a ton of information on studies regarding lab testing involving aspartame and rats, yielding inconclusive evidence against popularized theories. Included are a couple just to prove a point:
In 1981, Ishii conducted research dosing aspartame to rats. He used 86 males and 86 females, dosing 0, 1, 2, or 4 g/kg bw/day from weeks 6 to 110 . The statistical variance in bodyweight discrepancy when comparing a rat to a man needs to be taken into account, and dosage would still remain proportionate to the body weight of the subject. The highest dose in this study was 4 grams per kilogram of bodyweight per day. This means that for a 200 pound man (90.909 kilograms) times 4 grams of aspartame per kilo gives you…363.63 grams every single day. One final computation to get back to milligrams so we are on the same playing field as our previous studies: 1000 mg= 1 g, so that gives us 363,363 milligrams of aspartame administered to a 200 pound man. Do you remember what the average consumption of an American is? 5 milligrams per kilogram of bodyweight, so for our example, 455 milligrams. The most interesting part of this would not even be the insanely high dosage of the sweetener, but that there was no increase in the incidence of brain tumors. So at literally 800 times the dose that one would consume on a day to day basis, over the duration of more than two years, there was nothing significant to compare to the control group. Just as a friendly reminder, a can of Diet Coke has 180 milligrams of aspartame.
There were though, some studies that indicate negative effects, cancer incidences, and the like. The thing with those is that they can be easily refuted, based on the sole understanding of dosage. In a popular study used to bash this sweetener, in order for there to be a statistical significance, the dosage of aspartame used was 2,500 mg/kg, which simply is not plausible. At the end of the day, everything is toxic at the right dose. That is like getting a study published when 50 subjects aged 30-40 received a dose of 3,000 grams of salt intravenously to see the mortality rate. (Then the headlines on the news would be “Study confirms that salt may lead to an early death.”) Looking over a toxicology report showing the LD50 (essentially the dose that will kill 50% of a given population) it is easy to see that even things you would never think could bring death, can, at the right dose. News reports over the years show people overdosing on water and drugs but anything can be deadly, in the right amount. Caffeine being roughly 200 mg/kg of bodyweight and Vitamin D being 10 mg/kg. The dosage makes the poison.
The bottom line is that there is simply not enough evidence to prove aspartame as carcinogenic over not, and even those that have even the slightest hint in their desired direction are easily picked apart and dissected down to nothing.
So, to sum this up, I figured it might be a little easier to relate all this back to the main point, our safety as consumers.
AS FAR AS ASPARTAME
(Remember, now we are talking about aspartame, the thing that in a long chain-like process is “linked to formaldehyde.”) The average American consumes 5mg/kg of aspartame per day, so for a man weighing 200 pounds, this equals 455mg per day. In a study lead by Stegink, a field of 30 adults were grouped to consume 100, 150, and 200 mg/kg, showing an increase in plasma methanol . This is where the media capitalizes and throws up a headline “Aspartame increases methanol in humans, leading to cancer.” Right away, *methanol was present, not formaldehyde, and certainly not formic acid. To begin, the researchers found that even 34 mg/kg of aspartame (3,182 mg) had an unmeasurable impact on blood concentration of methanol, 7 times more than the average American consumption. If you do the math from that study, the dose for a 200 pound man would be 18,182 mg in the “most abused” group. That is 39 times more than the average person in the US consumes, in one day! To sum up the results of the statistics, there was no change in blood formic acid concentration (even in comparison to pre-aspartame loading), and the amount that the methanol impacted in individuals was 100 times lower than the amount required to cause acute methanol poisoning for most people, with the lethal dose being estimated to be 100-500 ml.
So in simple terms, what does this mean? An easy conversion, in Stegink’s study, the total amount of aspartame to be consumed in order to reach the amount of methanol to reach the amount of formaldehyde to reach the amount of formic acid is equal to drinking 25 Liters of diet soda, sweetened with 100% aspartame, in one sitting. I don’t see anyone doing that.
ARTIFICIAL SWEETENERS AS A REPLACEMENT
I’m sure you are thinking, “Are you saying to drink a two-liter of Diet Coke every day?”
Of course not, but based on the research I can say I do not feel that it is unsafe to do so. Moderation is key and too much of anything will cause unwanted effects.
Instead of standing up for aspartame and other artificial sweeteners, ponder another approach. What could be consumed in place of artificial sweeteners? In the United States, obesity is the leading force behind the cost of health care. According to Heart.Org, in 2013, the cost of obesity was estimated to be 190 billion dollars. What are the key factors that leads to the massively increasing rate of obesity? Lack of exercise, and overconsumption of calories. One place to look when looking at the diet of the average American is the liquid portion, the soda that is consumed. Sugary beverages provide no sustenance or satiety, not to mention may have an impact on insulin sensitivity and perhaps resistance for the normal folk. As flexible dieters, we know that calories in versus calories out are the prime determinant in body composition. Although caloric and energy balance are key to maintaining a healthy weight, I would say that 98% of the population do not calculate macronutrients or measure their calories in any way. By replacing a daily soda beverage with a diet drink, or better yet water, caloric intake can be drastically cut day to day and will surely assist in the slimming on the waist size and help to live a healthier and longer life.
Genetics Home Reference. (2012). Phenylketonuria. Retrieved July 3, 2016, from: http://ghr.nlm.nih.gov/condition/phenylketonuria
http://m.cancer.org/cancer/cancercauses/othercarcinogens/intheworkplace/formaldehyde (Studies in People)
Heck HD, Cassanova-Schmitz M, Dodd PB et al. (195). Formaldehyde (CH20) concentrations in the blood of humans and Fischer-344 rats exposed to CH2) under controlled conditions. Am Ind Hyg Assoc J, 46: 1-3. Doi:10.1080/15298668591394275 PMID:4025145
Ishii H. Incidence of brain tumors in rats fed aspartame. Toxicol Lett. 1981;7:433–437.
Stegink LD, Brummel MC, McMartin K, Martin-Amat G, Filer LJ Jr., Baker GL, Tephly TR (1981). Blood Methanol concentrations in normal adult subjects administered abuse doses of aspartame. Journal of Toxicology and Environmental Health 7: 281-290.
Ziegler SL (1921) The ocular menace of wood alcohol. Br J Opthalmol 5:365-373, 411-417.