We want to fall pregnant or we do, and we are told to ensure we are taking iodine and folate. Cool okay sounds simple...
But is it really that simple?
Do we need anything else?
We have an exhaustive list of what to avoid?
Are we avoiding some foods we could actually benefit from?
We are growing not only a human being but another organ (placenta)! We need a variety of nutrients to assist these processes.
When it comes to Vitamin A – we are told to avoid eating foods that contain it due to high levels causing toxicity. But what is the risk of avoiding it?
Public Health guidelines do need to be this black and white for many reasons, this is completely understandable as it needs to be achievable by the masses and keep the general population safe. However, like everything in conception and pregnancy, there are nuances.
Vitamin A is one of these things. We are told that it can cause birth defects if eaten in high volumes. You may choose to make a different decision based on this and your diet/health
Vitamin A has an important role in fertility and hormone production; it is essential for early foetal development, contrary to what everyone focuses on, we need vitamin A for eye formation, genital/urinary tract development, brain development, diaphragm development, heart, kidneys and lungs (!)
It does important things for our lung function, immune system and the integrity of the gastrointestinal tract.
So as you can see - Vitamin A is a vital vitamin in pregnancy and conception!!
There are 2 forms: retinol (animal foods) and carotenoids (from plant foods) that your body can convert to retinol at some capacity, that process can be challenging especially to some individuals who have certain genetic variations on how their bodies function.
Beta-carotene and carotenoids function as antioxidants but they don’t actually function as vitamin A until your body goes through a process of conversion to retinol.
Firstly, Vitamin A is a fat-soluble vitamin. This means, you need fat to help absorb and utilise this vital nutrient. Fat in your diet is crucial for all fat-soluble vitamins (like vitamin D!)
We get Vitamin A in foods such as:
- Oysters, clams, mussels
- Animal fat: beef, pork, chicken skin, lamb
- Egg yolk
- Full fat dairy products
- And the most abundant, and nutrient dense: liver.
What about beta-carotene, that’s vitamin A, no?
Technically, yes. Beta-carotene which is found in many plant foods, CAN convert to retinol which is the active form of vitamin A. HOWEVER – there is a large number of people (45%) that cannot successfully convert beta-carotene to retinol due to a genetic mutation (BCM01) which means they end up with much less vitamin A intake. Plus, like all plant foods, it is a lower bioavailability unlike the higher bioavailability in animal products. So this is why we cannot rely solely on plant foods for our vitamin A intake.
Insufficient intake of vitamin a is really common – about 80% of women at reproductive age are generally not eating enough.
Albeit an older study, there was one in the 90’s in the Netherlands which suggested 70% of the women in the study who did not consume liver in their diet, did not meet the RDI of vitamin A. Liver is the most nutrient dense form of vitamin A. A serving of chicken liver equates to approximately 1600IU which is well below the upper limit of 10,000IU (daily).
If you’re not consuming liver – you’re probably going to be in that high percentage of women not meeting the RDI of Vitamin A!
Since the year 2000, there have been 700,000~ babies born with the defect called congenital diaphragmatic hernia – where the diaphragm does not form properly. This is quite serious and has been linked to potential vitamin A deficiencies (!!) Because people are too scared to take ANY vitamin A, even in their multi vitamin.
What should you be looking for in your prenatal vitamin?
Well firstly, most prenatals contain beta-carotene which as above, isn’t all that effective. You want to find one that has the active form which will either be an option of:
- Retinol palmitate
- Or beta-carotene with retinol palmitate
Unfortunately even in prenatals, there is only typically a small amount ranging from 600-1000IU.
The issue with beta carotene is, the more we we get (dietary and supplements), it is actually harder for the body to utilise and convert to it’s active form, retinol. Just to make it extra complicated ;)
Like everything else, vitamin A conversion requires cofactor nutrients such as high quality zinc (which is in most prenatals if not all) and protein. Both are also found in animal products, which have a high bioavailability.
So why are we told not to take it?
The studies were predominantly done in the 1990’s. The concerns were women with high dose of synthetic retinoids had a higher risk of certain birth defects among the women in the study. This lead to the concern over “excess” vitamin A intake in pregnancy.
There are some metabolites most associated with birth defects. Research is now suggesting these metabolites are coming from synthetic forms of vitamin A, rather than food sources ie liver.
Fewer than 20 cases have been reported over a 30 year period of excess vitamin A intake causing birth defects. And none of those are contributed to the consumption of liver.
Who is at risk of a vitamin A deficiency?
Those who have diets that lack vitamin A intake such as Vegan diets, plant based diets, veggo’s or taking beta-carotene in supplements.
If liver is a no-go for you, look at a prenatal with RDI for optimal amount of retinol palmitate or you could supplement with cod liver oil under the advice of a practitioner.
If you’re interested in adding liver to your diet I would recommend by starting once a week adding chicken or beef liver in to a mince dish like a Bolognese where you cannot really taste it (it is an acquired taste). You could purée it up and freeze it in portions in silicon freeze containers.
Other options include store bought (or homemade) pâté, powder form, capsules, frozen liver grated in to a smoothie or juice or curry/stew/Bolognese etc.
Small bird livers have a more mild taste, hence why many find it easier to opt for chicken livers, as larger animals = larger livers, arguably more nutrient dense, but stronger flavour.
references
Strobel, Manuela, Jana Tinz, and Hans-Konrad Biesalski. “The importance of β-carotene as a source of vitamin A with special regard to pregnant and breastfeeding women.” European Journal of Nutrition 46.9 (2007): 1-20.
Gannon, Bryan M., Camille Jones, and Saurabh Mehta. “Vitamin A requirements in pregnancy and lactation.” Current Developments in Nutrition 4.10 (2020): nzaa142.
Rai, Deshanie, et al. “Nutritional status as assessed by nutrient intakes and biomarkers among women of childbearing age–is the burden of nutrient inadequacies growing in America?.” Public health nutrition 18.9 (2015): 1658-1669.
Ross, Sharon A., et al. “Retinoids in embryonal development.” Physiological reviews 80.3 (2000): 1021-1054.
McGivern, Mark R., et al. “Epidemiology of congenital diaphragmatic hernia in Europe: a register-based study.” Archives of Disease in Childhood-Fetal and Neonatal Edition 100.2 (2015): F137-F144.
Yang, Wei, et al. “Nutrient intakes in women and congenital diaphragmatic hernia in their offspring.” Birth Defects Research Part A: Clinical and Molecular Teratology 82.3 (2008): 131-138.
Beurskens, Leonardus WJE, et al. “Retinol status of newborn infants is associated with congenital diaphragmatic hernia.” Pediatrics 126.4 (2010): 712-720.
Allen, Lindsay H., and Marjorie Haskell. “Estimating the potential for vitamin A toxicity in women and young children.” The Journal of nutrition 132.9 (2002): 2907S-2919S.
Russell, Robert M. “The vitamin A spectrum: from deficiency to toxicity.” The American Journal of Clinical Nutrition 71, no. 4 (2000): 878–884.