If the purpose of science is to explain and understand, a number of organizations that embrace the scientific method and publish regularly on public health are not doing a very good job of either. About a month ago, I posted information about a study suggesting that sucralose, the nation's leading sugar substitute, might be a cause of cancer. Now sucralose's nutritive non-sugar sweetener counterpart, aspartame, has become the subject of a highly publicized scientific debate over its potential toxicity.

Aspartame has been used widely since the 1980s in various food and beverage products such as diet drinks, yogurt, breakfast cereal, toothpaste, and even in some medications such as cough drops and chewable vitamins. Consumers rely on products containing aspartame and other sweeteners to reduce their sugar consumption. 

The International Agency for Research on Cancer (IARC) released its aspartame hazard and risk assessment results Friday. The IARC classified aspartame as “possibly carcinogenic to humans.” At the same time, the Joint Expert Committee on Food Additives affirmed the principle that a daily intake of 40 mg/kg body weight of aspartame is acceptable and does not pose a risk to human health. The World Health Organization took a middle ground, stating: “The assessments of aspartame have indicated that, while safety is not a major concern at the doses which are commonly used, potential effects have been described that need to be investigated by more and better studies.” Finally, the Food and Drug Administration (FDA), expressed its disagreement with the IARC’s conclusion claiming that there is no evidence linking aspartame to cancer. The regulatory and scientific authorities of various countries, including Health Canada and the European Food Safety Authority, have also deemed aspartame safe at currently permitted use levels.

In my view, the upshot of all this modern-day "science" can be explained and understood by harkening back to the teaching of Paracelsus, the sixteenth century physician, alchemist, and philosopher, who is often referred to as the father of toxicology: "only the dose makes the poison." Used in moderation, aspartame is probably fine. Used in excess, aspartame, like all chemical compounds, may not be safe.