By Dena McDowell, MS, RD

As a clinical oncology dietitian, one of the most common questions that I hear is "Does aspartame cause cancer?" A recent Google search using the words "cancer" and "aspartame" brought up 503,000 articles related to this question. Because there is so much information about aspartame it is easy to become confused. This article provides information on what aspartame is and the safety related to chronic disease states.

What is aspartame?

Aspartame was created in 1965 by researchers looking for a sugar replacer for the food industry. It is composed of phenylalanine and aspartic acid which are two amino acids, and methanol which is a form of alcohol. This compound is about 200 times sweeter than sugar and is used in many foods such as soft drinks, sugar replacers, instant tea, gelatins, puddings, candy, cookies, pie filling, non-dairy toppings, and creamers, as well as ice cream.

Is aspartame safe?

The Food and Drug Administration (FDA) reviewed aspartame's safety in 1981 and determined it safe as a food additive. Research is ongoing to determine if aspartame intake is positively correlated with chronic diseases such as cancer. To date, there has been no evidence to show that aspartame consumption is linked to the development of chronic disease. In April of 2007, the following statement was released: "The FDA finds no reason to alter its previous conclusion that aspartame is safe as a general purpose sweetener in food."

How much is safe?

Acceptable Daily Intake (ADI) levels for aspartame are determined by an expert panel called the Joint Expert Committee on Food Additives (JECFA), which is part of the United Nations, World Health Organization, and the Food and Agriculture Organization, in partnership with the United States FDA. The ADI is the amount of an additive if eaten every day during a person's lifetime would not cause harm. The ADI for aspartame in adults is 50 milligrams per kilogram of body weight. This level was determined after studying the effects of aspartame in rats. No adverse effects were seen in rats fed 4 grams of aspartame per kilogram of body weight. This level was then divided by 100 to determine a safe level of consumption in the human population. To put this into perspective, a 150-pound person could consume 3500 milligrams of aspartame daily without causing bodily harm. In one can of aspartame-based diet soda, there is an average of 180 milligrams of aspartame. Therefore, a 150 pound person could drink 19 cans of diet soda everyday without seeing adverse effects of aspartame.

Other health concerns for aspartame

The Center for Disease Control in Atlanta has received numerous reports of adverse effects of aspartame consumption, including headaches, dizziness, and stomach upset. Other claims related to aspartame consumption include Alzheimer disease, birth defects, diabetes, multiple sclerosis, attention deficit disorder, and seizures. There is no research to show that aspartame is related to any of these conditions.

It should be noted that babies born with phenylketonuria (PKU) should not consume aspartame. PKU is an inborn error of metabolism and does not allow the body to digest the amino acid phenylalanine. Food products that contain aspartame (also known as NutraSweet and Equal) must include a warning that the product contains phenylalanine and persons with PKU should not consume it.

The bottom line: the ADI of aspartame is safe

Although research is ongoing, products containing aspartame are generally considered to be safe. As long as consumption of aspartame is within the ADI, no chronic health issues should be seen as a result of ingestion.