My parents grew up on rural farms. One day as a kid I was having a grand old time on a hulking fertilizer cart in a granddad’s barnyard. Mom came out of the house and was – to say the least – distressed. It turned out the cart’s technical name was “manure spreader”.
Mom had a fixation on cleanliness, but any residue in the cart was only cow manure: mostly plant matter (lignin is my guess) after being washed by the rains and baked by the sun during weeks of disuse. The stuff is tame. Towns even host discus-throw or shot-put events for hurling dried cow pies / chips / patties. I suppose food-like names reflect society’s tolerance for the material, in fact a common name for horse manure also evokes food – road apples.
But I digress. Human waste seems to be more dangerous. Some discussion of the structure may be helpful so I’ll digress again. Bacteria make up over half of the dry mass. That biome routinely accommodates several hundred species, yet only four phyla (three dozen or so species) represent 99% of the biomatter. For reasons still unclear their ecology tends to gravitate toward one of three main equilibrium states, depending on which is the dominant group – the starch-loving Bacteroides, mucus-eating Prevotella, or sugar-enabling Ruminococcus.
Some species are quite hazardous, notably C. difficule, but a well-balanced gut biome can whip the troublemakers into shape. Thus, we have fecal microbiota for transplantation (FMTs) – also known as fecal transplants – to achieve rapid control of C. difficule. This summer the FDA issued a warning and tabled clinical trials, noting that an FMT left a patient dead from multi-drug resistant organisms (MDROs). However even as cautions surface, science keeps discovering new medical uses for fecal microbes – from microbial competition and endurance-enhancing lactate metabolism to anti-obesity properties and anti-Alzheimer’s effects.
Some people view the FDA as more hindrance than help on this issue, but really the situation reflects an industry in the making. Wholesale transfers of gut microbes are an efficient way to treat a condition when we don’t understand the health intricacies of that biome. The same situation exists for the appendix. But it is indiscriminate – right up there with using lice to clean wounds. And MDROs are not the only issue – for instance, an FMT can be a prelude to obesity.
Hence new cautions are just a breather while the field gets a better handle on tweaking microbial ecology. Or at least until it begins creating targeted bacterial ferments with controls against drug resistance. Entrepreneurs would even call it a business opportunity, since there’s a clear need and cultivation should provide more uniform products and more predictable results.
A search finds that gut microbes in capsules are already on the drawing board, as probiotics. The thought of swallowing the stuff evokes a visceral reaction, but maybe that’s just me. If it ever comes to that, I’d rather have an enema of artificial feces – say, from mixing ferments with a hydrogel and fiber matrix. Yet either way, Mom would have been horrified.
Food for Thought:
Circling-V ™ 