Liver! Let me explain…
In the vast world of medicine there is a small but very important subsection that revolves around optimising foetal health. Years and years of research have gone into perfecting the knowledge behind this topic. At this point in time, we’re pretty clued up on what to encourage and what to avoid when it comes to the diet and lifestyle of an expectant mother. There’s the generic things like stop drinking and smoking, eat more vegetables, and try to remain active. That stuff is obvious. Then there’s this whole other world of knowledge that we seem to have stopped teaching about and instead have just decided to enforce, which is a damn shame because it’s all so interesting.
So what’s this got to do with polar bears? Let’s dive right in.
I’ll Take Retinoic Acid for 600 Points, Alex
You may or may not have heard of the word “teratogenic” before. This basically describes anything that may disrupt the normal development of the foetus. So while the few cells in your uterus are dividing and specialising and morphing and sculpting and all that good stuff, these teratogens are substances that can and will affect this healthy development.
Quick note: Folic acid is a good example of this. Without correct supplementation of folic acid, the developing foetus is at a much higher risk of being affected by neural tube defects. Which, to be very reductionist, are issues with the baby’s spine. Some of these are so severe that the foetus is no longer compatible in life and so the woman may miscarry. Trust me on this, neural tube defects are very sad and unfortunate outcomes that still affect countless mothers and babies around the world. This is reasoning behind the aggressive encouragement to start taking folic acid supplement as soon as you start trying for a baby.
Okay, getting back on track – another teratogenic substance to avoid is called retinoic acid. For the purposes of this article, this is the fancy scientific term for Vitamin A. We know from good, solid research studies that too much of this substance is actually teratogenic to the foetus. What does it do? It affects the mid-craniofacial development.
Cyclopia and Retinoic Acid
Let’s quickly digest this that piece of information. As your cells develop and you take on the form of a healthy foetus inside the uterus, your cells and the signalling molecules that they release form a sort of axis to guide development. This helps when it comes to orientating the growth of the various parts of your body with respect to a midline of the body so things like knowing where your arms and legs go, where your sternum will be placed, which side your heart will be, etc. It’s super important for your cells to have an idea of where the middle of your body is.
Now, if the midline of the axis is disrupted, say somewhere like the face, then suddenly the cells don’t know where your nose should go, where the middle of the lips are, how far apart your ears and eyes should go, or even – whether you have two eyes or not.
Holoprosencephaly is the result of this issue. This is a group of foetal developmental disorders that occur because of faulty development of the midline of the face as well as the forebrain. Real nasty stuff. One of the ways this then presents is cyclopia – the presence of a single eye in the midline. That’s right, just like the famous myth of the cyclops.
So, Polar Bears?
Right let’s round this up. So we know that certain substances are teratogenic and can cause really bad issues in early development. An example of this retinoic acid, or Vitamin A, and too much of it in the diet of a pregnant woman can lead to cyclopia, which is a type of holoprosencephaly. This is the reason we actually advice pregnant women to avoid taking in too much vitamin A from the diet. One of the main recommendations is to avoid liver since this is where most of the animal’s liver is stored.
And which animal’s liver contains the most amounts of vitamin A? You guessed it, polar bears!
So a note to all pregnant women: I know it may be tempting, but don’t eat polar bear livers while you’re pregnant.
Ending Note
Now I could go on and on about the intricacies of this topic. There are so many interesting topics to delve into regarding teratogenic effects of different substances. There have been some incredible landmark studies that have shown us how those axis form in our developing cells and how our cells know where, when, and how far to divide. I could even talk tons about cyclopia and other ways it has presented throughout history. This can of worms is only slightly ajar for now…
But look, at the end of the day, if you’re a pregnant woman reading this and you’re now scared about all the possible things you may be eating that you should be avoiding – don’t panic. Chances are you’re fine. Obviously take that with some common sense (stop drinking and smoking) but in general if you follow a normal, healthy diet you don’t have to worry about these things. And for the love of all that is logical, get your kids vaccinated.