Am I the only one who's ever thought that a fully plant-based diet simply cannot be entirely natural because plants don't supply enough vitamin B12? This was a reason why I continued eating fish long after I'd stopped eating meat, and longer still after I'd given up consuming dairy products. I concluded that a diet that doesn't supply all the essential nutrients must be flawed. Now that my diet is fully plant-based, I take supplemental B12, so what about the absence of vitamin B12? Was there something wrong with my earlier conclusion?
It's now well-known that vegans, and to some degree vegetarians, should supplement with this vitamin because their diet will most probably be deficient. This is one occasion where the word 'should' gets past my filter (I'm not a big fan of 'should') because deficiency symptoms are serious; from a type of anaemia, to nervous system disturbances and mood problems as well as digestive and cardiac concerns. Does this then mean that their diet is inadequate, irrespective of the quality of their food? I'm confident now that this is not the case at all and that omnivores might be well advised to also consider supplementation.
It's easy to assume that as our ancestors most probably had enough of the vitamin in their diets, they must have obtained it from animal sources. Maybe. Maybe not. Vitamin B12 is produced by certain bacteria so neither by plants nor animals, but rather micro-organisms that find their way on or into food, and this may include plant foods, however the levels of B12 from plant sources is usually insufficient and thus simply unreliable. Interestingly though, studies have demonstrated that it isn't unusual for meat eaters to also be B12 deficient. Why might this be? Could it be difficulties with absorption? Certainly. For example, as more and more people show up at GP surgeries complaining of digestive issues, especially acid reflux, the more they're likely to leave with a prescription for Proton Pump Inhibitors which means (assuming the presenting issues weren't already inhibiting B12) poor absorption is far more likely once the patient is taking the medication; this drug negatively affects vitamin B12 absorption. Antibiotics, on the other hand, may kill off the useful bacteria in the digestive system and this is especially problematic for anyone given multiple courses of these drugs. But some of the problems with this vitamin are more widespread and require that we look at our food system and how we live today.
It's little wonder that plants are an unreliable source of bacteria-producing B12; many of them are sprayed with multiple pesticides whose role is to extinguish organisms that are considered pests, they don't make a distinction between 'good' and 'bad', and neither does the chlorine that is often used for washing our produce; pathogenic bacteria must certainly be avoided which makes washing somewhat indispensible, but in doing so, we must acknowledge the loss of diversity in the micro-organisms we consume and this may include the vitamin B12-producing bacteria.
But what about meat? Animal feed isn't subject to the level of sanitation that humans demand, but it can be impacted anyway; if animals are given chlorinated tap water, if they eat foods grown with pesticides, and if they're medicated with antibiotics, then the bacteria in their digestive tracts will struggle to survive and their meat will have less or none of the vitamin B12 that is assumed to be there. This makes things potentially a little precarious for meat eaters! Shifting from mass-produced to grass-fed and organic meat might be helpful, but may still not provide an absolute guarantee of good B12 levels.
For better and worse, we are all subjected to the effects of our modern life. Where vitamin B12 is concerned, it may be relevant for more of the population to take a supplement, or at least consider being tested now and then.
~ Annette Henry
Some of the information and inspiration for this post is from Drs Rick and Karin Dina. For more about them please see their website: Raw Food Education