Caffeine for the microbiome: intakes linked to reduced “detrimental” strain
The results suggest an inverse relationship between the caffeine consumption and Erysipelatoclostridium; a species which research has previously associated with adversities such as increased obesity risk, inflammation, and poor blood glucose control.
In addition, it was noted that both caffeine and coffee consumption were associated with increased bacterial diversity, as well as the abundance of Faecalibacterium and Alistipes species. However, this association did not remain significant following adjustment for B2 levels.
“Our study sheds light on the associations between caffeine intake and coffee consumption and the gut microbiota of individuals with endoscopically normal colons. The association between caffeine, gut microbiota, and health outcomes and the role of Erysipelatoclostridium in metabolic diseases deserves further investigation,” the US-based researchers stress.
Caffeine and the gut
The consumption of caffeine has been a long-established tradition, with its intake associated with increased alertness and energy due to antagonising the adenosine A1 and A2 receptors. Yet, increasing evidence has suggested further health benefits, with studies noting reductions in the risk of developing cardiovascular disease, Parkinson’s disease, and diabetes.
There have been suggestions attributing such benefits to the consumption of coffee, due to its ability to modulate the microbiome, with findings highlighting increases in beneficial bacteria such as anti-inflammatory Bifidobacterium species.
It has been observed that coffee contains an array of bioactive compounds, including phenolic compounds, alkaloids, and diterpenes. However, the minimal data investigating the specific phytochemicals within the coffee responsible for the observed effects highlights the need for further study.
Thus, the researchers conducted the cross-sectional study comparing the mucosal-associated microbiotas of 34 healthy Texas-based adults aged between 50 and 75 using 16S rRNA gene sequencing, to assess the effects of both caffeine and coffee intakes.
Following the genetic sequencing of the 97 donated colonic biopsies from the sample, food consumption was determined by administering a food frequency questionnaire. The relative abundance of bacterial taxonomies was then compared by low (<82.9 mg) vs. high (≥82.9 mg) caffeine intakes, as well as by never or <2 cups vs. 2 cups vs. ≥3 cups of coffee intakes.
Whilst it was established that both higher caffeine and coffee intakes were associated with a significantly increased bacterial diversity and an increased abundance of Faecalibacterium and Alistipes, these findings did not remain significant after adjusting for vitamin B2 using multivariate analysis.
However, a significantly lower noted abundance of Erysipelatoclostridium did remain significant following such analysis, suggesting an inverse relationship between the species and caffeine intakes.
The present study provides insight into the relationship between caffeine and coffee intakes and the microbiota, highlighting the potential for intakes to reduce species associated with adverse health outcomes.
The researchers highlight: “Higher Erysipelatoclostridium levels have been linked to diet-induced obesity in mouse models and obesity in humans. A previous study showed that patients with type 2 diabetes had higher Erysipelotrichaceae levels than patients with normal glucose tolerance.
“There is growing evidence showing the adverse roles of Erysipelotrichaceae and Erysipelatoclostridium play in host lipid metabolism, immune response, inflammation, depression, metabolic-associated fatty liver disease, cancer, and response to cancer immune therapy,” they add.
With regards to the further findings suggesting enhanced diversity and increased abundance of Faecalibacterium and Alistipes species, the report highlights that the health effects of coffee may be partially explained by vitamin B2; a prebiotic that is richly present in coffee.
Following these findings, the scientists urge further studies to investigate this relationship further to explore the associated health outcomes.
“The Association between Caffeine Intake and the Colonic Mucosa-Associated Gut Microbiota in Humans—A Preliminary Investigation”
by Annie Dai, Kristi Hoffman, Anthony A. Xu, Shawn Gurwara, Donna L. White, Fasiha Kanwal, Albert Jang, Hashem B. El-Serag, Joseph F. Petrosino and Li Jiao