Bacteria on the brain: Carnivores, herbivores, and B12
Today we're going to dive into another way in which bacteria play a vital role in human lives. Like viruses, bacteria are able to affect our brains. Here, we're focusing on a way in which this can be to our benefit!
We will be investigating research behind a vitamin that only bacteria have the power to produce: Vitamin B12! This vitamin is necessary for, among other things, building the DNA in human cells. This means that B12 is essential in every single cell of our body! Vitamin B12 is also required for the human body to produce many proteins. At a cellular level, proteins are the machines that keep everything running smoothly - so this makes B12 a pretty big deal. To top things off, B12 is also necessary for the breakdown of fats, which provide 'fuel' for protein machines to do their work. This vitamin is a multitasking superhero!
But what about the role of B12 in the brain that I started off by hinting at? It turns out that vitamin B12 also works closely with folic acid, which many pregnant women take as a supplement to foster brain health in the growing fetus. This partnership between folic acid and B12 is important not only for fetuses, but also for adults! Studies have found that folic acid and vitamin B12 may be involved in a whole range of neurological diseases, from mood disorders to dementias.
At this point, you're probably convinced that vitamin B12 is a pretty big deal. But how do we get it, if it's only made from bacteria? This has recently been somewhat of a hot topic in nutritional science, especially with the increasing popularity of vegetarian and vegan diets. As many meat-eaters with primarily herbivorous friends may know, meat and milk from animals - especially ruminant animals like cows and sheep - are rich in vitamin B12. This is because there is a huge amount of B12-producing bacteria in the stomachs (indeed, plural stomachs - each ruminant animal has more than one stomach) of ruminants! It's all about the bacteria in the end.
However, because it comes down to bacteria, it's not only animal products that contain B12. Considerable amounts of B12 have been found in plants like sea buckthorn and elecampane, as well as lower amounts in mushrooms. But one of my favourite sentences from a scientific paper describing B12 content in plants was as follows: "Organic fertilizers such as cow manure appear to slightly increase the B12 content of spinach leaves." In normal phrasing, the key is poop! Poop is filled with bacteria that produce B12, so plants growing in poop contain more B12. In fact, it is now thought by some scientists that poop may have been the primary ancestral human source of B12. This hypothesis (educated guess) is based on research in chimpanzees. Us humans weren't always as hygienic as we are in this day and age, after all.
But, don't despair! If you're vegetarian or vegan, which are risk groups for B12 deficiency, poop is not your only option. Not only are there vegan/veggie-friendly supplements, but recent research has also found that some fermented foods like tempeh and kimchi contain some vitamin B12. The bacteria in these foods represent a far more sanitary option for getting some good bacteria!
Until next week - keep washing your hands, but try some kimchi!