Vitamin A Toxicity
Ok, let's get into the big pregnancy/ prenatal question…
What is vitamin A?
Let's first talk about what Vitamin A is and isn't..
True vitamin A retinol was the first vitamin to be discovered and comes from animal foods! This is called preformed Vitamin A because it is bioavailable and ready for use by the body.
On the other hand, there is PROvitamin A and contains all the members of the carotenoid family one of them being beta-carotene which you are probably familiar with. This type of vitamin A has to be converted in order to be used and comes from plants. The data shows that only three percent or less of carotenoids from plant foods are absorbed.
In contrast, eighty percent or more of preformed vitamin A from animal sources (i.e. liver) is absorbed.
Vitamin A…
- has been shown to reduce anemia during pregnancy
-plays an important role in iron metabolism
- is needed to turn cholesterol into your sex hormones
-is needed to help thyroid hormone receptors in cells
-helps the uptake of iodine and impacts thyroid metabolism
- is needed for fetal growth and development.
So where does all the fear come from?
There were some older studies that linked high dose synthetic Vitamin A supplements to birth defects.
The problem with these studies is that they were given high doses of straight synthetic vitamin A (in excess of 10,000IU) Vitamin A never occurs naturally in isolation so it doesn't make sense to administer a study with a single nutrient in high doses. Of course, anything on its own in high amounts can be toxic. Secondly, when found naturally in food, Vitamin A is consumed alongside other fat soluble vitamins like Vitamin D and k2 which helps to support proper balance and utilization.
So how common is Vitamin A toxicity?
"Reported incidences of vitamin A toxicity are quite rare, with fewer than 10 cases per year… Teratogenicity is the most severe side effect of oral retinoids, affecting 1 in 57 women ingesting over 10,000 IUs daily of preformed vitamin A.
The beef liver I recommend (Perfect supplements) contains: 969 IU of Vitamin A per serving
The cod liver oil I recommend (Rosita) contains: ~1216 IU of Vitamin A per serving
That puts total Vitamin A at 2185 IU per day
The RDA for women per day is 2,333 IU
The RDA for pregnant women per day is 2566 IU
If you were to consume liver by eating it, the recommended amount is 3 ounces a week. Each ounce contains roughly 5000iu of Vitamin A so over a week this would equate to 2142 IU per day.
Keep in mind that RDA is considered the BARE MINIMUM amount you should be ingesting to meet the nutrient needs for most people.
That means even if you supplement with these you won't be at the RDA amount leaving you plenty of room to also have retinol in your diet from animal protein or dairy. Also keep in mind that not every single bit of what you ingest will be absorbed and used.
I think you will be surprised when you look below at common prenatal vitamins compared to beef liver.
"Ongoing concerns over vitamin A toxicity from liver consumption are perplexing, considering that deficiency is fairly common in pregnant women. One study found that one-third of pregnant women were borderline deficient, despite having access to plenty of vitamin A-rich foods. This essential nutrient is widely recognized for its role in normal growth and development during pregnancy, including the developing lungs, kidneys, heart, eyes, and other organs. Even the National Institutes of Health states, “pregnant women need extra vitamin A for fetal growth and tissue maintenance and for supporting their own metabolism.” Certainly, an excessive amount of any nutrient is problematic, and since vitamin A is fat-soluble, it does raise the risk of toxicity. However, given what we know about deficiency and the safety of food-sourced vitamin A, this does not defend the recommendation to avoid liver, our most valuable food source of the vitamin. (Lily Nichols, Real Food for Pregnancy)
Even if you supplement with beef liver and cod liver oil or only one of the two, you will be no where near going over the 10,000IU. Also keep in mind the Vitamin A you get from liver, cod liver oil and food is REAL. It has other vitamins and minerals alongside it that act synergistically or antagonize it to keep a level of homeostasis within the body. This is why consuming foods found naturally is always more beneficial than in a synthetic supplement.
This is also why I am always preaching to stop supplementing single nutrients. This doesn't just go for Vitamin A, but iron, zinc, and any others. Nutrients work together and are always found together naturally. That was by design and for a purpose.
This is not medical advice. All of the information shared is for educational purposes only. Discuss any supplement changes with your medical provider.
XO,
Meghan
P.S. - If you are wanting more support on your conception journey - my course, Fertility in Balance is for you! Waitlist is now open and you can join, here.
