Coffee is one of the most widely consumed beverages in the world and contains hundreds of biologically active compounds, including caffeine, chlorogenic acids, diterpenes, trigonelline, melanoidins, and multiple polyphenols. These constituents can influence glucose metabolism, inflammation, oxidative stress, liver function, the gut microbiome, and cellular signaling. For this reason, coffee has attracted considerable interest as a potential modifier of cancer risk and prognosis.
For patients with metastatic cancer, however, the clinically relevant question is not whether coffee prevents cancer in otherwise healthy adults. It is whether drinking coffee after a diagnosis of advanced cancer can slow disease progression, improve survival, enhance treatment tolerance, or meaningfully improve quality of life.
The answer is nuanced. Coffee consumption has been associated with favorable outcomes in several observational studies of cancer survivors, with the strongest evidence coming from colorectal cancer. Most notably, a large prospective analysis embedded within a randomized clinical trial found that patients with advanced or metastatic colorectal cancer who drank more coffee experienced longer overall survival and progression-free survival. (1) Nevertheless, coffee itself has not been tested as an anticancer treatment in a randomized trial, and there is insufficient evidence to conclude that coffee improves prognosis across metastatic cancers generally.
Coffee should therefore be regarded as a potentially beneficial dietary exposure—not as a cancer therapy, a substitute for systemic treatment, or a universally appropriate recommendation for every patient.
Coffee Is More Than Caffeine
Coffee and caffeine are often discussed as though they were interchangeable, but this is misleading.
Caffeine is only one component of coffee. Coffee also contains:
Chlorogenic and caffeic acids
Ferulic acid
Trigonelline
Cafestol and kahweol
Melanoidins produced during roasting
Magnesium and other micronutrients
Numerous volatile and nonvolatile phytochemicals
Some epidemiological associations are observed with both caffeinated and decaffeinated coffee, suggesting that non-caffeine constituents may contribute materially to any benefit. This is particularly relevant in colorectal cancer studies, where both caffeinated and decaffeinated coffee have been associated with more favorable outcomes. (2).....................
Full text:
