If you believe everything you read on the internet, then is seems that a chemical found in thousands of products is causing an epidemic of severe neurological and systemic diseases, like multiple sclerosis and lupus. The FDA, the companies that make the product, and the “medical industrial complex” all know about the dangers of this chemical but are hiding the truth from the public in order to protect corporate profits and avoid the pesky paper work that would accompany the truth being revealed. The only glimmer of hope is a dedicated band of bloggers and anonymous e-mail chain letter authors who aren’t afraid to speak the truth. Armed with the latest anecdotal evidence, unverified speculation, and scientifically implausible claims, they have been tirelessly ranting about the evils of this chemical for years. Undeterred by the countless published studies manufactured by the food cartel that show this chemical is safe, they continue to protect the public by spreading baseless fear and hysteria.
Hopefully, you don’t believe everything you read on the internet, and you don’t get your science news from e-mail SPAM, where the above scenario is a common theme. While there are many manifestations of this type of urban legend, I am speaking specifically about aspartame – an artificial sweetener used since the early 1980s. The notion that aspartame is unsafe has been circulating almost since it first appeared, and like rumors and misinformation have a tendency to do, fears surrounding aspartame have taken on a life of their own.
I am frequently asked my opinion about the safety of aspartame. Nutritionists often council to avoid the sweetener, citing unverified claims that it is unsafe. I was recently sent a chain letter warning that aspartame causes MS (which of course can be cured by simply avoiding aspartame), and Snopes informs me that this particular letter first appeared in 1998.
There are also hundreds of websites dedicated to smearing this much abused food additive. One site, run by Dr. Janet Starr Hull (she has a doctorate in Nutrition), responds to the latest report of aspartame’s safety by writing:
I will never accept the news of aspartame safety. I think it is a “business” decision to discredit/discount the research results that aspartame DOES cause cancer, major nerve disorders, birth defects, and brain imbalances. Think about it – can you imagine the chaos that will occur when the truth of aspartame dangers is accredited. The FDA has known about the dangers, the corporations have known about the dangers, and the medical community (if it is really worth anything) has known about the dangers.
The statement that “nothing will ever convince me” is a huge red flag that someone is defending an ideological position, one immune to evidence or reason. Admittedly, in context it could be a clumsy statement that something is very unlikely. It would be very difficult to convince me that the earth is flat – I’m really saying that the existence evidence is overwhelming that the earth is not flat. But that is not what Dr. Hull is saying. She is specifically saying that she will dismiss any evidence that is contrary to her belief that aspartame is not safe on the a-priori basis that such disconfirming evidence is part of a vast conspiracy.
Of course, Dr. Hull also sells an aspartame detox kit, which might lead a cynical person to conclude that she cares more about selling alternative health products and stoking her sales with some unreasonable fear than about scientific evidence.
What evidence does she have for such a conspiracy? The argument from final consequences logical fallacy – big industry wouldn’t want it. It’s also not very plausible. Products get pulled from the market all the time when new evidence suggests they are not safe. Also, the final safety net for the consumer is legal liability. Class action law suits have bankrupted companies, even when the underlying claims were false. Imagine if they were true. Look how much the tobacco industry has had to fork over.
Now I am not arguing that corporations are all good corporate citizens or wouldn’t dream of sweeping some inconvenient evidence under the carpet. But I am saying that a decades long conspiracy among industry, federal regulatory agencies, the medical community, and multiple research institutions and individual researchers – all under the nose of the press and lawyers looking for big class-action suits – is implausible in the extreme. I am also arguing that we should fairly assess all the evidence, not just cherry pick the evidence we like and dismiss the rest out of hand.
What does the evidence say about aspartame? A recent published review of all available evidence, including hundreds of studies, concluded:
The studies provide no evidence to support an association between aspartame and cancer in any tissue. The weight of existing evidence is that aspartame is safe at current levels of consumption as a nonnutritive sweetener.
Multiple reviews, going back to 1985, conclude the same thing. Since this latest review there have been more studies, in various countries (how big is this conspiracy?), showing no link between aspartame and brain cancer, and a lack of correlation between artificial sweeteners and gastric, pancreatic, and endometrial cancers.