Capsaicin has been identified as the primary component that contributes to the hotness of chili peppers. Around the world, chili peppers are a popular ingredient used in many kinds of food. There are many varieties of chili pepper and each offers a slightly different flavor and level of heat. In some communities they are even used as a food staple.
Over time, this ingredient and its possible role in cancer has become a subject of controversy. While some studies with capsaicin have shown that it can inhibit cancer cell growth and metastasis, other studies have shown the opposite result.
Recently, a study at Nanjing University focused specifically on a diet with high level of capsaicin and its impact on gastric cancer. This study used a xenograft mouse model of gastric cancer fed with a diet of either 50 mg/kg or 100 mg/kg capsaicin. This is the equivalent of a human consuming 90-250 mg capsaicin each day. The results showed that this type of diet led to increased metastasis rates and increased number of cancer nodules. Interestingly, the size of the tumors did not increase.
While other experiments have given evidence of capsaicin having anticancer properties, this study gives evidence of its cancer promoting properties. One key difference between studies is likely to be the concentration or intensity of the application. Perhaps at lower concentration and frequency of consumption, there is a beneficial effect, but with continual high concentration intake as in this study, the effects become detrimental. It seems chili peppers provide yet another example of ‘moderation is key’.
Deng R, Yu S, Ruan X, et al. Capsaicin orchestrates metastasis in gastric cancer via modulating expression of TRPV1 channels and driving gut microbiota disorder. Cell Commun Signal. 2023 Dec 21;21(1):364. PMID: 38129926