A polarising topic. 

Is coffee good for you? What answer does the gut microbiome have for this age old question?

Let’s look at some peer reviewed evidence.

The journal:

Nutrients

The paper:

Long-Term Coffee Consumption is Associated with Fecal Microbial Composition in Humans (May 2020).

The authors: 

Sonia González, Nuria Salazar, Sergio Ruiz-Saavedra, María Gómez-Martín, Clara G de Los Reyes-Gavilán, Miguel Gueimonde

Limitations: 

The sample size is 34 people. The inclusion criteria for the study required that the participants be healthy adults without any chronic diseases or gastrointestinal disorders. They also needed to be without any recent antibiotic use or other medications that could affect the gut microbiome

Is coffee good for your gut microbiome? Findings:

The study found that regular coffee consumption (at least 1 cup per day) was associated with changes in the composition of gut microbes in a dose-dependent manner. Specifically, the researchers observed a positive association between coffee consumption and the abundance of Bifidobacterium and Lactobacillus. As you have probably heard, these species are considered beneficial bacteria in the gut.

Furthermore, the study found that coffee consumption was associated with lower levels harmful bacteria, such as Enterobacteriaceae and Fusobacterium. 

Interestingly, long-term coffee consumption was linked with increased diversity of the gut microbiome. Considering microbial diversity is considered to be one of the most important markers of a healthy gut, that’s impressive. The study found that individuals who consumed coffee regularly had a greater number of bacterial species in their gut microbiome, as well as a more even distribution of these species.

Another interesting finding of the study was that coffee consumption was associated with increased levels of anti-inflammatory bacteria in the gut microbiome. These included Faecalibacterium and Roseburia. Faecalibacterium prausnitzii, for example, is a bacterial species that is known to produce butyrate, a short-chain fatty acid that has been shown to have anti-inflammatory effects in the gut. Low levels of Faecalibacterium prausnitzii are associated with inflammatory bowel disease and other gut-related conditions. Similarly, Roseburia spp. produce butyrate and other short-chain fatty acids that are important for gut health.

Why can coffee be beneficial for the gut microbiome?

The paper suggests that the beneficial effects of coffee on the gut microbiome may be attributed to its various components, such as polyphenols and chlorogenic acid.

Polyphenols are a type of antioxidant that are found in many plant-based foods, including coffee beans. Previous research has suggested that polyphenols may have prebiotic effects, meaning that they can promote the growth of beneficial bacteria in the gut.

Chlorogenic acid has been studied for its potential health benefits. Some research has suggested that chlorogenic acid may have anti-inflammatory properties and can promote the growth of beneficial bacteria in the gut.

The study did not specifically measure the levels of these compounds in the participants’ diets, so it’s not possible to say for certain. However, the authors speculate that the combined compounds may be responsible for the effects of coffee on the gut microbiome.

So there you have it, regularly drinking 1 cup a day of coffee may in fact be helping your gut microbiome to stay diverse and healthy.