Aspartame, Bipolar Disorder and Anxiety; how is this all connected?

BY SIMONE J. SMITH

The debate on the safety of yet another FDA approved substance remains at the forefront of numerous scientific studies, and for good reason. Regardless of the shiny accolades given around the substance, there are doctors and scientists who do not give aspartames a stamp of approval.

As aspartame’s popularity grew, so did questions about their effects. It was declared unsafe for people suffering from phenylketonuria, a rare hereditary enzyme defect, and those suffering were cautioned to avoid aspartame. According to the Mayo Clinic, the additive was also blamed for causing other illnesses, including cancer.

The artificial sweetener industry, represented by the Calorie Control Council, has contested these accusations, and later scientific studies appear to back some of the industry’s safety claims.

A 2007 review of aspartame studies in the “Critical Reviews of Toxicology” declared the additive safe for most people, but a 1994 study suggests that it may not be good for people with mood disorders. However, a 1994 study suggested that aspartame has a negative effect on patients with mood disorders.

Scientists who speak against the harms of aspartame have been challenged on their assertions that there are major problems with the use of aspartame in view of the fact that the bulk of the medical literature attested to its safety. In response, these scientists responded that one had to look carefully at study funding. Virtually all of the studies claiming safety were funded by the industry, whereas independently funded studies invariably identified one or more problems.

Let us take a look at the mood disorders in question: Bipolar Disorder, Unipolar Disorder, and Anxiety.

Bipolar disorder (also known as manic depression) is a genetic illness. Bipolar disorder symptoms manifest as extreme shifts of mood, from major highs to crushing lows. Although the illness cannot be cured, most patients can lead basically normal lives through: medication, therapy and healthy lifestyles.

In 1993, Dr Ralph G. Walton, former Psychiatry Department Chairman at North-eastern Ohio Universities, submitted a study of how aspartame affected unipolar disorder patients and individuals who did not have unipolar disorder. Members of each group were exposed either to aspartame or a placebo for a week. He had intended to recruit 40 people for the study, but had to stop the study after 13 people were signed up, because the negative impact of aspartame on the unipolar patients was too great to justify continuing the study.

In unipolar disorder, the patient does not have the major highs, but experiences severe depressions. Due to the fact that the two mood disorders are often found in the same families, it is thought that when a substance harms unipolar disorder patients, it may be off limits to bipolar patients as well.

An article on the MedScape Website titled, “Can a Common Artificial Sweetener Fuel Anxiety?” reviewed a new preclinical study released in December 2022. Investigators observed mice that drank water-containing aspartame. They noted that the mice exhibited pronounced anxiety-like behaviours in a variety of maze tests. This behaviour occurred at aspartame doses equivalent to less than 15% of the maximum daily human intake recommended by the US Food and Drug Administration (FDA).

“It was such a robust anxiety-like trait that I don’t think any of us were anticipating we would see. It was completely unexpected. Usually you see subtle changes,” said lead author Sara Jones, Doctoral Candidate at Florida State University (FSU) College of Medicine, in Tallahassee.

Medical News Today also published an article on the same research study titled, “Artificial sweetener aspartame linked to anxiety.”  The expanded on the research noting that the mice experienced changes in the expression of genes in the amygdala.

The amygdala is a part of the brain associated with regulating anxiety and fear. The researchers found that the drug diazepam could successfully alleviate anxiety. The study also found that changes in the amygdala persisted for up to two subsequent generations through males, as did the effectiveness of diazepam in relieving anxiety.

I have supported the research on aspartame and their damaging effects, because once again, this is a substance that is in several products that are used by the public, and unfortunately we do not hear enough about the harms that it causes.