Aspartame Activates Brain Cancer Genes, Study Finds
A recent animal study published in Scientific Reports investigated the effects of aspartame on gene expression and gut bacteria in mice with glioblastoma. Researchers assessed whether aspartame could influence tumor progression on a molecular level, even in the absence of visible tumor growth.1
•The mice used in the study had gliomas induced by transplanting cancerous cells — These test subjects were then split into two groups. One received aspartame in their drinking water, while the control group was given plain water.
•One of the most striking findings was the activation of cancer-linked genes — The researchers discovered dramatic internal changes — particularly at the genetic and microbial level — in the aspartame-exposed group. Specifically, they observed a significant upregulation of three key genes — myelocytomatosis (MYC), cyclin-dependent kinase inhibitor 1A (CDKN1A), and transforming growth factor-β (TGFB1).
•These three genes are well-established contributors to cancer progression — MYC is an oncogene, meaning it plays a direct role in driving uncontrolled cell growth, while TGFB1 is often associated with a poor prognosis in glioblastoma due to its ability to suppress immune function and promote tumor cell survival. CDKN1A is typically involved in controlling the cell cycle, but when dysregulated, it contributes to tumor aggressiveness.
•The most unsettling part? These changes happened without any measurable increase in tumor size. That means even if your tumor isn’t growing, it could still be genetically evolving into something far more dangerous.
Aspartame Alters Your Gut Microbiota by Affecting the Gut-Brain Axis
Aspartame was accidentally discovered in 1965 and had been used in consumer products since the 1980s. Being a low-calorie sweetener that’s 200 times sweeter than regular sugar, it became widely popular among people who want to cut back on their calorie consumption. It’s now used in over 6,000 different products worldwide, including diet soda, sugar-free gum and candy, and even condiments like ketchup and salad dressings.2
However, aspartame is not as safe as it seems — in fact, it has been associated with a long list of health problems, such as obesity, headaches, and depression.3 In 2023, the World Health Organization’s International Agency for Research on Cancer (IARC) declared aspartame as possibly carcinogenic to humans4 — and now, this animal study provides stronger evidence backing up this classification.
•The changes in gene activity were traced to a powerful biological process called RNA methylation — These changes occurred specifically along the N6-methyladenosine (m6A) pathway. RNA methylation is a chemical modification of messenger RNA (mRNA), the molecule your body uses to translate DNA into proteins.
This modification acts like a dimmer switch — it fine-tunes how active a gene becomes. When aspartame exposure elevated this process, the dimmer switch turned all the way up on cancer-promoting genes.
•Aspartame increases glioblastoma risk by affecting the gut-brain axis — This is the bidirectional pathway by which your gut and brain communicate with each other. Your gut bacteria synthesize short-chain fatty acids (SCFAs) like butyrate and metabolize dietary components like tryptophan into molecules that regulate the tumor microenvironment.
When these metabolites reach tumor sites, they improve immune surveillance mechanisms and alter cellular metabolic processes to inhibit tumor growth.
•Conversely, tumors also influence gut microbial composition — Certain gut bacteria that colonize tumor tissues contribute to carcinogenesis through multiple mechanisms — they induce DNA damage, suppress the immune system’s ability to recognize tumor antigens, and disrupt vital metabolic pathways. These create conditions conducive to tumor survival and proliferation.
To put it simply, some gut bacteria produce substances that help fight cancer, while others actually help tumors grow and spread; Aspartame alters your gut to increase the growth of tumor-spreading bacteria.
•Mice fed aspartame had a significant drop in bacteria from the Rikenellaceae family — Rikenellaceae are part of a group of microbes involved in producing SCFAs, which, as mentioned above, help inhibit cancer formation. According to the study authors:
“The composition and abundance of gut microbiota, particularly the Rikenellaceae family, are closely associated with the levels of volatile fatty acids, such as acetic acid, propionic acid, and butyric acid.
Numerous findings have provided compelling evidence of a robust connection between the abundance of the Rikenellaceae family in the gut and a diverse array of metabolic health conditions, including Parkinson’s disease and nonalcoholic fatty liver disease (NAFLD).
Our study concluded that although the aspartame diet did not significantly affect tumor growth, it did induce changes in the composition of the gut microbiota, particularly a decrease in the relative abundance of the Rikenellaceae family. We speculated that gut microbiota could influence the progression of glioblastoma multiforme by gut-brain axis.”5
Hellbound and Down 