Exploring science

I recently learned that aspartame, an artificial sweetener, is broken down into its components, the naturally occurring amino acids phenylalanine and aspartic acid, as well as methanol, upon ingestion by the digestive enzymes. My immediate thought was, “Dios mio, how ignorant have I been to think for so many years that aspartame is simply converted into amino acids?”

The methanol, similar to methanol obtained from other sources, is then converted by alcohol dehydrogenase into formaldehyde. Everyone knows formaldehyde (form + aldehyde) is toxic and can damage human cells and DNA. Fortunately, the enzyme aldehyde dehydrogenase metabolizes the formaldehyde into formic acid and carbon dioxide, which are less toxic and can be eliminated from the body.

The recent classification of aspartame as “possibly carcinogenic to humans” by the International Agency for Research on Cancer (IARC) has sparked concern among consumers and health professionals.
However, the Food and Drug Administration (FDA) disagrees with this assessment. FDA scientists reviewed the studies and identified significant shortcomings in the evidence.

While the link between aspartame and cancer is inconclusive, caution is warranted, especially with unregulated use.

The tragic case of the 10-year-old girl in India highlights the dangers of excessive sweetener consumption. Autopsies linking deaths solely to sweetener intake are uncommon, but this case underscores the potential risks associated with exceeding the Acceptable Daily Intake (ADI) of aspartame, particularly in unregulated settings.

Many small-scale bakeries offering sugar-free cakes may be unaware of the ADI for aspartame. Aspartame’s intense sweetness (200 times sweeter than sugar) can lead to over-use, potentially exceeding safe limits.

How Much Aspartame is Safe to Consume Daily?

The acceptable daily intake (ADI) of aspartame is set at 40-50 milligrams (mg) per kilogram (kg) of body weight.

This translates to a potential maximum methanol exposure of 4-5 mg/kg body weight per day.

For example, a person weighing 60 kg could potentially consume 2400-3000 mg of aspartame daily, resulting in a methanol exposure of around 240-300 mg.

The safety of aspartame, a widely used artificial sweetener, is a topic of ongoing debate. While the FDA considers it safe at recommended levels, some studies suggest potential risks.

Increased Risk of Stroke and Dementia:

A 2017 study in the Journal of Stroke found a link between higher intake of artificially sweetened beverages and an increased risk of ischemic stroke, all-cause dementia, and Alzheimer’s disease. The study suggests a tripled risk of developing dementia or stroke for those consuming one can of artificially sweetened drinks daily, with the risk rising proportionally with higher daily consumption.

Potential Neurotoxicity:

Some theories suggest that aspartame might overstimulate brain neurotransmitters, potentially leading to cell damage and contributing to dementia and memory issues. However, more research is needed to confirm this hypothesis.

Anxiety in Animal Studies:

A December 2022 study in the Proceedings of the National Academy of Sciences linked aspartame consumption in mice to anxiety-like behavior. This study raises concerns about potential long-term effects, but it’s important to note that animal studies don’t always translate directly to humans.

Learning and Memory Issues in Animal studies:

A September 2023 study by researchers at Florida University exposed mice to aspartame-sweetened beverages for 16 weeks. Compared to mice who drank only water, the aspartame-exposed mice took longer to find an escape route in a maze. While all mice eventually found the escape, the aspartame group required more time, suggesting potential learning and memory impairment. More research is needed to understand the implications for humans.

Aspartame Withdrawal:

Some individuals report experiencing withdrawal symptoms like headaches and anxiety upon quitting aspartame. However, further research is needed to confirm a cause-and-effect relationship between aspartame and these withdrawal symptoms.

The Aspartame Debate: What Do Dietitians Say?

With the ongoing controversy surrounding aspartame, understanding a dietician’s perspective is crucial. While registered dietitians like Meghan Windham acknowledge the debate, they generally agree that occasional consumption of diet soda isn’t a major concern. However, it’s important to focus on overall dietary patterns.

Beyond Aspartame: Looking at the Bigger Picture

The real concern lies with those who heavily rely on diet soda. While it might seem like a “lesser evil” compared to sugary drinks or substances like alcohol or drugs, it’s not an ideal long-term solution.

Addressing the Root Cause

Excessive soda consumption, diet or regular, can sometimes indicate deeper issues like emotional eating or unhealthy cravings. A dietician or therapist can help address these underlying causes to promote healthier beverage choices overall.