Akkermansia muciniphila is a species of gram-negative bacteria of the phylum Verrucomibia. It is a symbiotic member of the intestinal microbiota and is thought to make up 1% to 5% of the total microbial population in generally healthy individuals. A. muciniphila is a unique microbe because it uses mucin (a major component of mucus) as a preferred food source. Accordingly, A. muciniphila specifically resides in the mucus layer lining the gastrointestinal tract.^[2]

Akkermansia muciniphila is considered an important and health-promoting microbe and has recently been proposed as a novel probiotic.^[3]

Akkermansia muciniphila is thought to be an important member of the gut microbiome with a potential role in the maintenance of gastrointestinal and metabolic health.

In rodent studies, the administration of A. muciniphila has been reported to reduce intestinal permeability, obesity, fatty liver, and insulin resistance.^[4] However, there’s currently a lack of clinical trials confirming these effects in humans.

Some studies in humans suggest that higher levels of A. muciniphila in the gut are associated with better metabolic health, including reduced insulin resistance and lower levels of fasting glucose, insulin, leptin, and liver enzymes.^[5] Along this line, a smaller population of A. muciniphila in the gut could be associated with some health conditions, like obesity, type 2 diabetes, and inflammatory bowel disease.^[6][7][3] However, these findings are inconsistent, do not prove a causal relationship, and are unrelated to whether supplementing with A. muciniphila has any beneficial effects.

In humans, A. muciniphila supplementation has only been examined in a single, exploratory pilot study. The results suggested that A. muciniphila might benefit metabolic health in people with overweight or obesity and insulin resistance, but the study wasn’t designed to assess these clinical outcomes adequately.^[1]

Preliminary research suggests that live or pasteurized Akkermansia muciniphila is likely safe, but more clinical trials are needed to confirm if there are any potential side effects of A. muciniphila supplementation.^[8][1][9]

The major drawback of A. muciniphila is simply the lack of clinical research. It’s still largely unknown whether supplementing with A. muciniphila has any clinical effects.

Exactly how Akkermansia muciniphila works is still an area of exploration. Current research suggests that A. muciniphila naturally existing in our intestines may influence our health by directly interacting with aspects of the gastrointestinal tract and immune system and by producing metabolites like short-chain fatty acids (SCFAs). However, whether this applies to A. muciniphila taken as a supplement still needs to be determined.

A. muciniphila breaks down and feeds on mucin, the major component of the mucus layer that lines our gastrointestinal tract. This is thought to stimulate the turnover and production of mucus, which contributes to the health of the intestines. A. muciniphila also produces SCFAs, specifically propionate and acetate, as a byproduct of mucin degradation. These SCFAs are thought to regulate appetite, increase insulin sensitivity, decrease inflammation in the gut, and improve gut barrier integrity. Furthermore, A. muciniphila can interact with the immune system through Toll-like receptor 2 (TLR2), which regulates many biological functions, again including insulin sensitivity and gut barrier integrity.^{[10][4][8][3]}

Interestingly, a surface protein on A. muciniphila, Amuc_1100, has been shown to replicate many of the effects of live A. muciniphila in animal models, possibly through activation of TLR2. Amuc_1100 is also stable at temperatures used for pasteurization, which could explain why pasteurized A. muciniphila seems to maintain some of its effects.^[3][8]

The gut microbiome is very much its own ecosystem living within our intestines, and it’s important to note that A. muciniphila does not exist in isolation but rather as part of this complex ecosystem. The dynamic interplay between microbes within the ecosystem (and between our body and the gut microbiome) is complicated and only beginning to be understood. It’s quite possible that how A. muciniphila “works” relates less to its individual effects and more to its role within a larger ecosystem.