Dr. Amy Fan Conrad
Why you and your child probably need B12 supplementation, even if you eat meat

I am a proponent of getting as many nutrients and micronutrients from natural foods as possible. However, sometimes supplements become necessary and can make a huge difference. In that case, I think it's important to understand the "why," so let's dive into vitamin B12 - a popular topic lately that nevertheless has many misconceptions.
How do we get vitamin B12?
The common advice that only vegetarians and vegans need B12 supplementation might lead many to think that B12 is made by animal tissue, therefore meat eaters don’t need to worry about deficiency.
But the vitamin B12 is in fact not made by animals or plants, but by bacteria!
Our ancestors, along with animals in the wild, used to get our B12 from bacteria in the soil, carried by the plants and grains we ate, and from un-purified water we drank. As omnivores, humans also got this vitamin from animal products they ate when the hunt was successful. It’s important to keep in mind that the animals do not produce vitamin B12, but also depend on bacteria-made cobalamin (another name for vitamin B12), which is produced in their digestive tracks.
In other words, we get B12 first-hand from bacteria in the soil, and as a second-hand product by eating animal products.
What has changed?
With modern industrialization, humans have changed our environment in dramatic ways. With pesticides and chlorine, the bacterial flora of our lands has been altered to drastically decrease the vitamin B12 producing bacteria.
As a result, not only is our plant-based foods cleansed of this bacteria, so is the food of many animals we eat. Farm-raised animals now routinely receive B12 supplementation themselves as a result. In fact, more than 90% of this vitamin supplement is actually manufactured to give to farm animals. There is no good data that compares this post-supplementation value in animals compared to historic levels of wild animals our ancestors lived among.
As modern humans, we now have a lack of the primary and secondary sources for vitamin B12.
Why is B12 important?
Vitamin B12 is a crucial element for synthesis of our red blood cells. Medical literature is familiar with the symptoms of Pernicious Anemia, which results from improper absorption of B12, leading to hematologic and neurological issues. At these severe levels, we see symptoms such as tingling of hands/feet, severe anemia, neurologic decline, dementia, etc.
But what about low levels of B12 that are not severe enough to be detected in a blood test?
More recent studies show that while levels of B12 <100 lead to well recognized symptoms, a “lower range of normal” value between 100 and 200 can also lead to a wide range of unspecific symptoms.
What about for kids?
In children, sub-optimal B12 levels can lead to:
Fatigue
Irritability
Slow cognition
Lack of appetite
Delay or compromised growth / Failure to Thrive
Weakness
And yes, maternal deficiency in vitamin B12 is passed on to breastfed babies.
So what to do?
In the USA, children routinely go through anemia testing at age 1 and 2 through a complete blood count. However, B12 deficiency can be missed from this test because:
Levels might not yet be severe enough to show up
B12 deficiency characteristically leads to larger-than-usual red blood cells, while iron deficiency leads to the opposite (smaller than normal). As many toddlers also have iron deficiency, the two can mask each other and both deficiencies can be hidden.
There is always the option to specifically test for B12 in the blood. Alternatively, supplementation seems justified given the widespread mild-to-moderate deficiency. As B vitamins are easily excreted through urine in people with healthy kidneys, it’s very difficult to have a B12 overdose through proper supplementation.
So that is what I would recommend.
This topic has reminded me of how health is a fluid interaction with our environment, and guidelines have to change when our world does.
To symbiosis.
Much love,
Dr. Amy and the Kinder Team