How Safe IS Aspartame? - Daily Uptake

"The replacement of all sweeteners with aspartame has been estimated to yield an intake of 867 mg of aspartame/day, which translates to only 87 mg of methanol."
 

Before we can discuss aspartame toxicity, it is crucial to set the record straight regarding aspartame intake.

The statement in the article has three problems:
 

• The increasing use of aspartame has not lead to a decreased use in caloric sweeteners. According to the U.S. Department of Agriculture, the per capita consumption of aspartame quadrupled between the years 1983 and 1988 (USDA 1988). Since that time, the use of aspartame has continued to increase. Dr. H.J. Roberts reported on Wall Street Journal articles which stated that "the diet beverage market was increasing at a rate of 20-25% annually" and that "consumers began drinking up to six times as many diet drinks as those using sugared sodas." (WSJ 1988, WSJ 1989) Gregory Gordon wrote in a UPI Investigation that "Roy Burry, an analyst with Kidder-Peabody, Inc., said the exploding diet market now accounts for 24 percent of soft drink sales, compared with 10 percent in the late 1970s, and is growing at 20 to 25 percent a year" (Gordon 1987, page 484 of US Senate 1987).  From 1982 to 1988, the per capita consumption of caloric sweeteners jumped from 123.2 pounds to 133.5 pounds per year. Therefore the increased use of aspartame has not decreased the use of caloric sweetener products in the United States (USDA 1988).

• Studies have shown that when their diet is not closely monitored, many people use artificial sweeteners in addition to sugar products and not instead of sugar products (Chen 1991, Stellman 1986). Therefore, an increased use of aspartame will not necessarily alter the sugar-craving feeding behavior of the majority of persons. If they consume a non-sugar, aspartame-containing beverage at one point in the day, they will simply make up for the lack of sugar at some other point in the day. Some studies have shown an increased consumption of sugar due to aspartame (Blundell 1986).  In fact, Stellman showed that outside the confines of the highly structured, supervised environment, the subjects he surveyed who choose to use artificial sweeteners actually gained weight. Roberts (1988) showed  in his survey of people outside of the laboratory that 5% of the people reported adverse reactions had extreme weight loss when using aspartame and tended towards anorexia. He also noted that 6% of the respondents had a unexplained weight gain which averaged 19 pounds!

• Since diet products with aspartame have few calories and since many people have been conned into believing that they are safe, a significant percentage of people would  likely "throw caution to the wind," by drinking large quantities of diet soft drinks and eating large quantities of other products with aspartame. This is something that they would not be as likely to do with high-calorie, sugar-containing products.

The NutraSweet Company has been trying to convince people that persons who ingesting aspartame regularly ingest only 1-3 mg/kg (of body weight)/day of aspartame (Butchko 1991, Abrams 1992). This is based on surveys and diaries of consumers. What these surveys do not mention is that aspartame-containing products are often ingested as part of snacks and that people often forget what snacks they've eaten. This was aptly described by Dr. Richard Wurtman of MIT in a meeting with FDA officials on April 21, 1986 (Lisa 1994, page 201):

"[NutraSweet's estimates of current use] show, among other things, that people consume less aspartame in the summer than in other months, a  finding which violates good sense and reason. (This probably reflects the fact -- affirmed in our laboratories at MIT -- that people have much more difficulty accurately remembering snack than meal intakes . . . and most of the aspartame in the American diet comes via cold beverages and other snack foods.)"

Another set of similar surveys shows that persons living in Canada (7-day survey) have more than 2.5 times the daily  intake of aspartame than persons living in the U.S. (at the 90th percentile level of consumption). This is ridiculous because aspartame ingestion (the bulk of which comes from  cold diet beverages) in warm climates would almost certainly be much larger than in cold climates.

In addition, it appears that it is mathematically impossible for Canada to have an equal per capita aspartame consumption let alone a much greater per capita consumption. Aspartame net sales outside the U.S. amounts to only 10% of all net sales (Monsanto 1994)  Canada's population is 10.8% of the U.S. population (CIA 1994). Therefore, Canada's per capita intake of aspartame cannot possibly be even equal to that in the U.S., even in the extremely unlikely scenario where all aspartame sold outside the U.S. is sold only to Canada. (According to figures provided by the NutraSweet Company, the percentage of regular aspartame users in the United States and Canada are approximately the same (Farber 1989, page 56, Butchko 1991).

Another preposterous claim can be seen in a paper by Butchko (1991). In this paper aspartame consumption for 6-12 year old children was shown to decrease significantly from 1984 (the year after aspartame was approved for use in carbonated beverages) to 1989 despite nearly tripling the sales of aspartame from the middle of 1984 to 1989. (USDA 1988, Monsanto 1990). By the time this survey began the percentage of regular aspartame eaters in this age category was approximately 25% (Abrams 1991) according to NutraSweet Company figures. The NutraSweet Company admits that the use of aspartame had not risen to over 50% of the U.S. population at that time (Farber 1989, page 56). Therefore, an increase in the percentage of regular aspartame users could not have possibly accounted for the bulk of the increase in sales. Who are they kidding!? It shows that these surveys cannot be trusted to show anything close to accurate figures.

Perhaps another reason the average daily intake of aspartame from these surveys is so low is due to the way that the amount of aspartame ingested is calculated. For example, Abrams (1991) points out that what is recorded on these surveys is not the amount of aspartame ingested, but only "the number of times an APM [aspartame] containing item of food was eaten on that day by that person." This value is  then multiplied by the "average number of grams per eating occasion of that food for a person of that age and sex group" to give the total number of milligrams of aspartame ingested. However, the "average number of grams per eating occasion of that food for a person of that age and sex group" is drawn from a 1977-1978 USDA National Food Consumption Survey. Therefore, the calculations for the total milligrams of aspartame ingested is based on an old survey which is probably equally inaccurate as far as snack food ingestion goes and is most likely out of date. For example, these calculations assume that the average person would ingest the exact same amount of soft drink or diet food per item 1977 as they would in 1994. With the skyrocketing popularity of one- and two-liter bottles of soft drinks and the marketing push for diet foods, this is a ridiculous assumption. By making this assumption, NutraSweet are skewing the per capita intake figures and are using this "information" to justify studies on very small amounts of aspartame.

What the NutraSweet tries to show with flawed studies and surveys is often contradicted by other studies which they fund or by statements made by their representatives. In 1976, Frey showed that children who are 7 to 12 years old can have an aspartame intake anywhere from 35 mg/kg to 76 mg/kg per day when aspartame-containing snack food is not restricted (Frey 1976) (Note: No aspartame capsules were administered to the 7-12 year-old children. Only the 13-21 year-old children received capsules.). Three studies on obese individuals showed that their aspartame intake averaged 20 mg/kg per day (ranging from 8 to 36 mg/kg per day) (Porikos 1984). The Frey study and the three studies by Porikos monitored aspartame intake much more closely than the surveys often quoted by NutraSweet researchers. Those surveys relied on the ability of people to remember their snacks.

In an article from Science Times, Jane E. Brody states the following (Brody 1985):

"The drug agency has set an allowable daily intake of 50 milligrams of aspartame per kilogram of body weight, and the agency predicted that actual average use would run around eight to ten milligrams. According to Dr. Gaull of Searle, levels of use found in a national survey last spring showed that the average was then already twice that--19 milligrams--and the maximum level consumed by 'aspartame abusers' was 28 milligrams.  A United States attorney representing the F.D.A. said in court last month that average consumption is now 30 milligrams and that many consumers are above the 50 milligrams maximum suggested."

Farber gave an example of what a typical aspartame consumption may be for a child (Farber 1989, page 146):

"An 8-year-old of 20 kg, might eat the following:

 "This would equal 52.5 mg/kg of aspartame consumption....' [Note that even for a 60 kg adult, the above-listed example  would amount to over 17 mg/kg per day.]

On a hot Summer day, the child may ingest the aspartame listed above and several more carbonated beverages. There may be many children who are ingesting a full 2-liter bottle of pop during an active Summer day (1100 mgs. of aspartame).  On top of that ingestion, there may be Jell-O, cereal, gum, and many other aspartame-containing foods.

It is important to note that all aspartame-containing products of the same type do not contain the same amount of aspartame. For example, a one liter bottle of diet cola averages approximately 560 mg of aspartame. However, orange soda contains as much as 930 mg of aspartame per liter (Federal Register 1984). In addition, the Tsang (1985) study showed that there may be an addition 10% or more amount of aspartame in the product than what is claimed by the manufacturer.

Neuroscience researcher and Professor of Medicine at the University of California, Dr. William Partridge testified about the intake of aspartame before the U.S. Senate (Pardrige 1987):

"The first question is the dosage problem. We are led to believe by the FDA this morning that the typical consumer will have 2 to 4 milligrams per  kilogram of aspartame per day; that the 99th percentile intake is 34 milligrams per kilograms  per day; and that the advisable daily intake or ADI is 50 milligrams per kilogram per day."

"Now, the layperson sitting in the audience is really in no position to analyze these esoteric numbers. But if we put it in a different context and recognize that 50 milligrams per kilogram per day is equal to 5 servings of NutraSweet per 50- pound body weight, we can see that children, owing to their reduced body weight, are at a great risk  for overconsumption of NutraSweet."

"All one has to do in this room is look up at that chart and ask yourself if a 50-pound or 60-pound 7 year-old is going to consume 5 or 6 servings of that per day. If they are, then they have consumed 50 milligrams per kilogram per day, or the advisable daily intake."

"Now, an 11-year[-old] study in the literature has already shown this, that the average 7-to-12-year-old, when made freely available to products like that, consumes 5 servings per 50-pound body weight per day, and up to 77 milligrams per kilogram per day."

In the National Soft Drink Association's draft objection to use of aspartame in carbonated beverages it was stated (NSDA 1983):

"FDA relied upon an intake value of 34 mg/kg/day in assessing the possible risks of aspartame, describing that level as the '. . . highest obtained from any estimate of potential consumption and exceed[ing] the 99th percentile consumption (25 mg/kg) for all age groups . . .' 48 Fed. Reg. at 31377. For a 30 kg child, however, it would not be unusual for that level to be (phenylalanine) levels, even exceeded. For example, if a 30 kg child consumed on a warm day after exercise approximately two-thirds of a two- liter bottle of soft drink sweetened solely with aspartame, that child would be consuming 700 mg of aspartame, or approximately 23 mg/kg. This alone roughly equals what FDA considered, the 99th percentile consumption level. If during the day this child consumed other aspartame-sweetened products, the exposure level could quickly [reach] FDA's so called 'loading dose' of 34 mg/kg. 48 Fed. Reg. at 31377."

Had the child in the above example consumed two-thirds of a two-liter bottle of aspartame-sweetened orange soda, the values could be as high as 1240 mg of aspartame or 41.3 mg/kg/day for a 30 kg child.

Another way to look at intakes is to look at what a child may ingest in a single sitting. At the popular convenience store chain, 7-11, the drinks, "Big Gulp" and "Super Big Gulp" are popular items for both children and adults. A 30kg child purchasing a Big Gulp (32 ounces) of diet soda would ingest 510 mg to 846 mg of aspartame depending upon whether it was diet cola or diet orange. This works out to between 17 mg/kg or 28.2 mg/kg of aspartame in a single sitting! The same child purchasing a Super Big Gulp of diet soda would  ingest 700 mg to 1162 mg of aspartame. This works out to 23.3 mg/kg or 38.7 mg/kg of aspartame in one sitting! As an adult who plays basketball outside in the warm whether, I  know many people, including myself who can easily drink twice the amount of liquids as found in a Super Big Gulp in one sitting in order to prevent dehydration.

What is generally agreed upon when discussing the intake amounts of aspartame is the following:

The majority of aspartame users ingest much less than the FDA's Acceptable Daily Intake (ADI). When plotting milligrams per day of aspartame ingested against the percentage of  U.S. population, a smaller percentage of the population will ingest the largest amounts.

However, a regular, smaller dose of a neurotoxin such as aspartame is not necessarily safe and certainly not health-building. Dr. Roberts found many serious adverse effects from ingestion of aspartame at levels many times lower than the FDA's ADI (Roberts 1990a, page 71-72). The use of aspartame for a lifetime at even very small levels is foolish in my opinion.

Looking a studies I have seen in the literature as well as USDA figures for artificial sweetener usage, I would estimate that the average person in the U.S. who ingests aspartame regularly ingests approximately 8 mg/kg per day.

This is based on the following estimates:
 

• Approximately 35% of the U.S. population (81 million people -- CIA 1994) are regular aspartame "eaters." Heybach (1988) showed that in adult women (a population likely to have a higher percentage of regular aspartame users than the general population), only 25% ingested aspartame in the survey. Since the survey was only a single day, I will give the NutraSweet Company the benefit of the doubt and assume 35% regular usage for the general population. The FDA submitted an aspartame intake survey to the U.S. Senate which admitted that  approximately 35% of the survey participants were regular consumers of aspartame (FDA PMS 1987). I do not believe the contrived NutraSweet Company estimates that more than 50% of the U.S. population uses aspartame regularly.

• The average weight of regular aspartame users I estimate to be 50kg. This includes many thin women, adolescents, children, and infants who would tend to bring the average way down.

• The amount of aspartame used in the U.S. in 1995 I estimate is 28 million pounds. McNamara (1995) stated that 20 million pounds will be sold in the U.S. in 1995. The author probably got that figure from the NutraSweet Company and does not realize that every "fact" spewed out by this company is suspect at best. Figures from the USDA (1988) showed that 7 million pounds were consumed in 1984 and approximately 17.1 million pounds were consumed in 1987 Given that aspartame is now in over 5,000 junk food products worldwide (Geha 1993, Trefz 1994) and was only in hundreds of products in 1987, and given that diet beverage sales have increased tremendously in the last 8 years, an estimate of 28 million pounds is quite reasonable (This estimate is  probably too low. The actual figure may be as high as 35 million pounds.)

It is possible to determine the average usage of aspartame in regular eaters using the following formula: (lb. * 1,000,000 mg/kg) / (2.2 kg/lbs. * days/year * # of eaters  * kg/person) = 8.6 mg/kg/day for regular eaters. I realize that this is an estimate, but given how ridiculous the "results" of NutraSweet-connected surveys are, an estimate is better than nothing.

I believe that at least 10 percent of regular aspartame users ingest at least 20 mg/kg per day. This may amount to over 8 million people in the U.S. I would estimate that nearly 1 percent of aspartame users ingest at least 50 mg/kg per day. This may amount to over 800,000 people. This group would most likely be mostly made up of children and young, adolescent girls due to their low body weight and high intake of junk foods. For many of these people, the warm and hot weather intake will far exceed their Winter intake, such that a person ingesting 20 mg/kg per day in the Winter may  ingest 40 mg/kg per day in the hot Summer months. According  to Dr. Woodrow Monte, Director of the Arizona State University Food Science and Nutrition Laboratory, a significant number of people in Arizona drink as much as two or three liters of diet soda every day during the Summer (Monte 1995).

Even if we accept the FDA's projection that only 1% of the regular aspartame users will consume more than 34 mg/kg/day of aspartame, that still may amount to over 800,000 people. While the national average may be lower than 34 mg/kg/day of aspartame, there are undoubtedly several hundreds of thousands of people who are consuming well over 34 mg/kg/day of aspartame, especially on hot Summer days.

NutraSweet researchers sometimes use the following ploy to try and convince gullible listeners that people cannot ingest over 20 mg/kg/day or approach a level of 50 mg/kg/day  (despite their own studies which prove them wrong). They compare the amount of one single product that would need to be ingested by an adult male in order to reach these high levels (e.g., Rowen 1995). For example, they might say that  it takes 100 packets of Equal or 19 cans of diet soda for a 70kg man to reach a dose of 50 mg/kg.

First of all, not everyone is a 70kg man. Many people are 50kg women or 20-30kg children where the amount of aspartame required to reach a dose of 50 kg/mg is much less. Secondly, many people who put themselves at risk by ingesting aspartame do so using a wide variety of aspartame-containing "food" products such as soda, puddings, cereal, hot chocolate, coffee, tabletop sweeteners, gum toppings, supplements and pharmaceuticals, fruit drinks, etc. People abusing themselves with aspartame in this way can easily ingest hugh doses. Finally, even doses of only a few mg/kg/day is not safe in the long run.

Some researchers try to argue that they can use much less than the current FDA Acceptable Daily Intake (ADI) in their experiments as long as they use a test dosage well above the average intake of aspartame as determined by these (flawed) surveys. Stegink states the following (Stegink 1989):

"Initial consideration of these projected intakes might lead one to question their validity since 12 oz of aspartame-sweetened beverage ingested by a 27-kg 8-year-old child would account for 7.4 mg aspartame/kg body weight. However, when beverage intake data are examined, the projected aspartame intake values are consistent with these data. For example, Morgan et al reported that 7- to 8-year- old children ingest, on average 6.0 ± 4.2 oz soft drink daily (mean ± SD; value includes both regular and diet beverage) (Morgan 1985). Thus, an average 27-kg 8-year-old child would ingest 3.7 mg aspartame/kg body weight daily if all 6 oz of beverage were sweetened with aspartame. A 27-kg child ingesting beverage at 2 SD above the mean (approximately 97% of expected values) would ingest 14.4 oz of beverage. This would provide 8.9 mg aspartame/kg body weight if all beverage  consumed was sweetened with aspartame. Therefore, young children would have to drink unusually large quantities of beverage to ingest much larger quantities of aspartame."

What Stegink neglects to mention is the following:
 

• The study cited by Stegink (Morgan 1985), does not take into account that, as Dr. Wurtman stated, snacks are commonly forgotten in daily food surveys so that the average ingestion of soft drinks would likely be much greater.

• The study cited by Stegink uses data from a three-day survey instead of the more accurate seven-day survey.

• The study cited by Stegink was published in 1985. This study was an evaluation of data from the 1977-78 Nationwide Food Consumption Survey. Thus, the data was over ten years old when Stegink cited it and is now over 16 years old! Anyone adult in the U.S. who was not in a coma for the last 16 years knows that soft drink consumption has increased tremendously since the late 1970s.

• Stegink neglects to mention that there are thousands of products with aspartame and that 7- to 8-year-old children can be ingesting significant amounts from foods and beverages other than soft drinks.

While the average intake may be relatively low, although much higher than reported by Stegink and not necessary safe, there are undoubtedly a significant number of 7-to 8-year old children who are ingesting large quantities of aspartame by their own choice or by the choice of their parents to avoid sugar. It is ridiculous to use the "average" (even if it was accurately determined) to judge test amounts of aspartame.

Conclusion

NutraSweet-written survey summaries show a negligible increase in daily aspartame consumption since 1983. Aspartame sales has skyrocketed since 1983. Therefore, the numbers from these surveys which are flawed as described by Dr. Richard Wurtman above, do not make any sense and should be ignored until large, well-designed surveys are conducted separate from the influence of the NutraSweet Company. Until that time, estimates of average consumption for regular eaters at 8 mg/kg/day, 20 mg/kg/day at the 90% level, and over 50 mg/kg/day at the 99% level seem quite reasonable.

The NutraSweet Company researchers have begun a concerted effort to convince scientists and laypersons that they are testing high doses of aspartame. This is based on consumer surveys. The reality is that a) the surveys are flawed; b) their own studies show subjects ingesting much higher intakes of aspartame than they use in tests; and c) they are often testing using doses significantly below the FDA's Allowable Daily Intake (ADI). Their efforts to test small doses is a big con job. Don't buy into it.

What should be used in experiments is double the ADI of real world aspartame. Any argument for using less should be taken as an admission that the ADI is not a safe amount of aspartame.