Anecdotal evidence has given aspartame, often sold as Nutrasweet or Equal, a bad name. "Aspartame accounts for over 75 percent of the adverse reactions to food additives reported to the FDA," reports Mercola.com. It has been blamed for multiple sclerosis-like symptoms, headaches, dizziness, heart palpitations, joint pain and depression.
History of Aspartame
A chemist who was looking for a drug to treat gastric ulcers discovered aspartame in 1965, according to Janet Starr Hull, Ph.D. It has remained a controversial sweetener ever since its manufacturer, G.D. Searle, first sought approval from the Food and Drug Administration, FDA, to put it on the market.
In 1977, the FDA chief counsel wrote a 33-page letter to U.S. Attorney Samuel Skinner urging a grand jury investigation of the company for making false statements about aspartame's safety. In 1981, three of six FDA scientists recommended against allowing its sale.
Aspartame and Depression
In 1993, scientists at Northwestern University designed a double-blind, controlled study testing the effects of aspartame on depressed persons. The experimental protocol called for 40 depressed subjects to be given capsules containing either aspartame or a placebo. Another 40 not suffering from depression were also to receive either aspartame or a placebo. The experiment was never completed because the effects of aspartame on the first 13 depressed subjects were so severe, the Institutional Review Board, which works to protect human research subjects, stepped in to halt the experiment. The authors of the study, published in Biological Psychiatry, emphasized that aspartame did not affect the moods of the subjects not suffering from depression.
Animal Studies
Because it is ethically problematic to do neurological research on humans, many early studies used animals to study the effects of aspartame. In one 1987 study published in "Food and Chemical Toxicology," mice were given a daily dose of aspartame for 30 days before being killed to have their brains examined. Concentrations of serotonin, a neurotransmitter involved in mood regulation, were lower in several regions of the brain among these mice. Researchers theorized that the amino acid phenylalanine, a building block of aspartame, prevented the uptake of tryptophan, the amino acid that is a precursor to serotonin.
Alternatives to Aspartame
While many use aspartame without apparent ill effects, some have sought alternative sweeteners, unwilling to risk possible harm. One of those is stevia, also virtually calorie-free. According to a study published in the "International Journal of Toxicology," rats given varying doses of stevia showed no ill effects. Their behavior was unchanged, blood tests were normal and every organ examined appeared healthy. Many products sweetened with stevia, including soft drinks, are now on the market, making it easy to replace aspartame with this sweetener. However, according to a Mayo Clinic article, pregnant and lactating women should avoid stevia. This organization also recommends that everyone limit themselves to one or two servings of this sweetener per day.
References
- "Sweet Poison"; Aspartame History Highlights; Janet Starr Hull; September 2008
- "Biological Psychiatry"; Adverse Reactions to Aspartame: Double-blind Challenge in Patients From a Vulnerable Population; R.G. Walton; July 1993
- "Food and Chemical Toxicology"; Effects of Repeated Doses of Aspartame On Serotonin and Its Metabolite In Various Regions of the Mouse Brain; R.P. Sharma, et al.; August, 1987
- Mercola: Aspartame
- "International Journal of Toxicology"; A 90-day oral (dietary) toxicity study of rebaudioside A in Sprague-Dawley rats; A.I. Nikiforov, et al.; January-February 2008
- Mayo Clinic; Medical Edge Newspaper Column: Stevia --- a New Zero-calorie Sweetener; September 18, 2009
