Carbon is an element with several isotopes, atoms with the same number of protons but different numbers of neutrons. The most common isotope of carbon is 12C, which has six protons and six neutrons. Another isotope of carbon is 13C, which has six protons and seven neutrons. 13C is naturally present in small amounts in all living organisms, but it can also be artificially enriched and used as a tracer for various purposes (Lee et al., 2018).

One of the applications of 13C is to study the metabolism of cancer cells, which are known to have altered metabolic pathways compared to normal cells. By feeding cancer cells with 13C-labeled nutrients, such as glucose or amino acids, and measuring the distribution of 13C in different metabolites using mass spectrometry or nuclear magnetic resonance, researchers can quantify the fluxes of carbon atoms through different metabolic reactions. This technique is called 13C metabolic flux analysis (13C-MFA) and it can reveal the metabolic characteristics and vulnerabilities of cancer cells (Lee et al., 2018).

However, 13C can also have harmful effects on cancer cells and normal cells. 13C is a heavier isotope than 12C, and this difference in mass can affect the kinetics and thermodynamics of biochemical reactions. For example, 13C can slow down the rate of glycolysis, the process of breaking down glucose into pyruvate, which is essential for energy production and biosynthesis in cancer cells. This can impair the growth and survival of cancer cells that rely on glycolysis (Zhang et al., 2019).

Moreover, 13C can also induce oxidative stress and DNA damage in cancer and normal cells. Oxidative stress is a condition where there is an imbalance between the production and removal of reactive oxygen species (ROS), which are molecules that can damage cellular components such as lipids, proteins, and DNA. DNA damage can lead to mutations, genomic instability, and cancer development. 13C can increase the production of ROS by interfering with the electron transport chain, the process of transferring electrons from nutrients to oxygen to generate energy in the mitochondria. This can result in the leakage of electrons to oxygen and the formation of ROS (Zhang et al., 2019).

Aspartame expose humans to 13C

One of the sources of 13C exposure for humans is aspartame, an artificial sweetener used in many food and beverage products. Aspartame is made from two amino acids, phenylalanine, and aspartic acid, that are bonded together by a methyl ester group. During production, aspartame is fortified with 13C to increase its stability and shelf life (Little & Kirkland, 2016). However, this also increases its potential toxicity, as when aspartame is consumed and metabolized, it releases 13C-labeled methanol, which can be converted to formaldehyde and formic acid in the body. These compounds can cause oxidative stress and DNA damage, as well as affect the nervous system and vision (Little & Kirkland, 2016).

Therefore, 13C is a dangerous isotope that can cause cancer by affecting the metabolism and DNA integrity of cells. It is important to use caution when using 13C as a tracer for metabolic studies, as it can have unintended consequences for cellular physiology and function. It is also important to avoid or limit the consumption of aspartame-containing foods or beverages that are fortified with 13C during production. 13C is not just a harmless label, but also a potential carcinogen that can alter cellular biochemistry.

Can Aspartame Cause Cancer?

Recent studies have found that Aspartame can cause cancer. In our body, proteins are metabolized in the digestive process and then metabolized into amino acids. Aspartame is broken down into phenylalanine and aspartic acid during digestion. 

Can Acesulfame-K and Aspartame Cause Cancer?

Why Aspartame and Acesulfame-K Cause Cancer.

Sources:

Little, R. B. (2022). Evidence of Stable Isotope 13C Causing All Cancers. European Journal of Applied Physics, 4(4), 37–44. https://doi.org/10.24018/ejphysics.2022.4.4.187

Lee, J., Kim, H., & Lee, S. Y. (2018). A guide to 13C metabolic flux analysis for the cancer biologist. Experimental & molecular medicine, 50(4), e453. Retrieved from https://www.nature.com/articles/s12276-018-0060-y

Zhang, Z., Chen, L., Liu, M., Zhang, X., Lin, X., & Liangpunsakul, S. (2019). Carbon-13 tracing reveals elevated production of ROS by fatty acid oxidation in alcohol-induced liver injury models. Scientific reports, 9(1), 1