Vitamin A, a fat soluble vitamin, is responsible for many major processes in the body.
So, is there such a thing as too much? Can eating too much Vitamin A lead to birth defects during pregnancy? Where can you find it, anyway?
Read on to learn more about Vitamin A, its benefits, when too much is too much, and where to find it in your diet.
We also include a food list for those following a plant based diet.
Why Vitamin A is Important During Pregnancy
Vitamin A (retinol) is a fat-soluble vitamin that is responsible for multiple processes, including vision, immune system function, cell communication, and the reproductive system.
It helps to promote healthy and normal growth and development of organs in the body.
It’s especially important for pregnant women to consume adequate amounts of Vitamin A, and it can help to prevent deficiency in your baby after birth.
Deficiency could occur with diarrhea or with inadequate amounts of breastmilk and colostrum (breast milk produced in the first 24 hours following birth).
Deficiency can also lead to increased risk for infection for you and for the baby, including infections like measles.
Premature babies are also at risk for deficiency, as they do not get the chance to store ample amounts of Vitamin A before birth.
GI diseases, lung diseases like cystic fibrosis, and eye diseases can all occur in children born with Vitamin A deficiency (Source: NIH)
Vitamin A and Early Pregnancy
During the very first part of your pregnancy, in the first trimester, your baby starts as a tiny embryo.
The cells will divide over and over until a baby starts to form. Vitamin A (retinol) is an important part of this process.
Research shows that retinoic acid molecules are one of the cells responsible for the duplication of embryonic cell tissue.
Without Vitamin A, your precious baby could not form (Source: American Journal of Clinical Nutrition).
Vitamin A Limits: How Much Should I Be Getting When Pregnant?
Vitamin A needs fluctuate based on age and pregnancy status.
Vitamin A is measured in micrograms of Retinol Activity Equivalents (RAE), but was previously measured in International Units (IU).
Note that this is no longer recommended, as there is no direct correlation between IU and retinol measurements (source: FDA).
One microgram of RAE is equal to 12 micrograms of Beta-carotene, and 24 micrograms of other carotenoids like alpha-carotene.
While carotenoids can be converted into Vitamin A, they are not as bioavailable as Vitamin A (more on Beta-carotene later) (Source: Federal Register).
Here is a helpful breakdown of needs by age:
- Birth-6 months; 400 mcg RAE
- 7-12 months; 500 mcg RAE
- 1-3 years old; 300 mcg RAE
- 4-8 years old; 400 mcg RAE
- 9-13 years old; 600 mcg RAE
- 14-18 years old (female); 700 mcg RAE
- 14-18 years old (male); 900 mcg RAE
- Pregnant teenage women; 750 mcg RAE
- Pregnant adult women; 770 mcg RAE
- Breastfeeding teenage women; 1200 mcg RAE
- Breastfeeding adult women; 1300 mcg RAE
- Adult men; 900 mcg RAE
- Adult women (not pregnant/breastfeeding); 700 mcg RAE
The most common side effect of Vitamin A deficiency in pregnant women and young children is a condition called xerophthalmia, or decreased ability to see in low light conditions.
If left untreated, this can lead to blindness.
Deficiency is more common in less developed countries, and can usually be remedied with supplementation and dietary adjustments.
What Happens if I Get Too Much Vitamin A During Pregnancy?
Vitamin A toxicity (taking too much Vitamin A) can occur if you eat more than you need for an extended period of time.
Vitamin A can build up in fat and lead to toxicity, but it does not happen overnight.
The tolerable upper limit for Vitamin A is 3000 mcg RAE per day, which is thought to be the safest, highest amount that can be consumed on a daily basis.
Toxicity could present as nausea, vomiting, sensitivity to light, blurry vision or sudden changes in vision, bone pain, or dry skin (Harvard).
Although Vitamin A is essential during pregnancy, there are some foods (such as liver) that are so high in it, you should eat them in moderation. These foods are covered later on in this article.
It is also important to note that using topical products containing retinol (such as skin cream) does not contribute to Vitamin A toxicity, as it cannot be absorbed into the bloodstream.
Does Vitamin A Cause Birth Defects?
Excessive Vitamin A intake has been associated with increased risk for birth defects, but be wary of what you read on the internet from unverified sources.
Teratogenicity, or birth defects formed in utero, has been reported in some animal studies. These birth defects have also been reported in children whose mothers were treated with retinoic acid during pregnancy.
There can be disruptions and malformations of the bones to the face and head, dysfunction in the cardiovascular system and the central nervous system, and malformations in the thymus (a gland between the lungs which influences the immune and endocrine systems during childhood).
There has only been ONE prospective study done on retinol intake and birth defects, and the results and study itself have been widely criticized.
However, there are about 20 case reports published over the last three decades outlining the relationship between excessive Vitamin A/retinol intake and the risk of birth defects.
A clinical trial conducted in Hungary showed that maternal supplementation with 1800 RAE per day did not increase the incidence of fetal birth defects.
Since 1990, five case-control studies have been published regarding the relationship between Vitamin A intake and birth defects in babies.
In most of the studies, there was no direct correlation between intake and defect, and there weren’t enough participants to establish any statistical significance (American Journal of Clinical Nutrition).
Many articles regarding Vitamin A intake warn against the dangers of birth defects from consuming too much during pregnancy, but the warnings are generalized and tend to be somewhat vague.
The advice also differs from country to country. In the USA, women aren’t told to avoid liver, for example, but in the UK, they are (source: NHS).
The tolerable upper limit for Vitamin A for teens age 14-18 is 2800 mcg RAE, and women over age 19 is 3000 mcg RAE.
This is more than three times what is recommended, and is the amount that can safely be consumed before health risks start to become a concern.
Therefore, unless you are consuming excessive amounts of liver (or cod liver oil), the risk for Vitamin A toxicity may be relatively low (NIH).
In fact, one article stated that birth defects appear in about 1 in every 57 births when the mother consumed more than 3,333 mcg RAE.
Another article did report that birth defects were increased in babies whose mothers took some oral acne medications that include isotretinoin, which is a form of retinol (Source: New England Journal of Medicine).
The bottom line is this; eating a single meal high in Vitamin A is probably not going to hurt you or your baby. Remember you DO need vitamin A – just not too much of it.
Eating a lot of meals high in Vitamin A could pose a health risk to you and your baby. So, moderation is key.
Check out the following list of foods to see what you can eat and what should be eaten in moderation:
Foods High in Vitamin A: What to Eat and What to Avoid
Generally, supplementation with Vitamin A is not recommended unless a deficiency is suspected.
Deficiency is not widespread, especially in the USA and Europe; it’s most common in Africa and Southeast Asia.
However, during pregnancy, and especially in the third trimester, the risk for deficiency can increase with increased blood production and fetal development. (WHO)
It’s generally recommended that pregnant women avoid eating liver, as it’s so high in Vitamin A that it could lead to Vitamin A toxicity.
However, liver is still very nutritious and offers a great source of protein, iron, and other valuable nutrients.
It would be advisable to be aware of portion size when consuming liver, and only consume well-cooked liver from a trusted source to reduce the risk of foodborne illness.
Here is a breakdown of 14 foods highest in Vitamin A:
- Duck liver; 13541 mcg RAE per 4 oz serving (113 grams)
- Turkey liver; 9106 mcg RAE per 4 oz serving (113 grams)
- Lamb liver; 8352 mcg RAE per 4 oz serving (113 grams)
- Beef liver; 5614 mcg RAE per 4 oz serving (113 grams)
- Liverwurst; 2250 mcg RAE per 8 oz serving (55 grams)
- Cod liver oil; 1350 mcg RAE per teaspoon
- Tuna; 1114 mcg RAE per 6 oz serving (170 grams)
- Eel; 1043 mcg RAE per 100 grams
- Hot and Cold fortified cereals (wheat flakes, cream of wheat, oatmeal, etc); 300-600 mcg RAE per serving (varies by cereal)
- Goat cheese; 138 mcg RAE per ounce (28 grams)
- Butter; 97 mcg RAE per tablespoon
- Eggs; 80 mcg RAE per egg
- Clams; 76 mcg RAE per 3 oz serving (85 grams)
- Milk (varying milk fat percentage); ~75 mcg RAE per 8 oz serving (240 milliliters)
Source: Nutrition Advance
One interesting fact is that, because Vitamin A is a fat-soluble vitamin, it needs to be consumed with fat for absorption.
This means that you will not get the same Vitamin A benefits from drinking fat-free milk or using fat-free milk in cereal vs. milk with some fat.
Vitamin A and Beta Carotene During Pregnancy
There are two main forms of Vitamin A; Preformed Vitamin A (retinoids, or retinol) which is in animal products, and provitamin A (carotenoids) which can be found in fruits and vegetables.
Since preformed Vitamin A is only found in animal products, those following a plant-based diet may not get adequate amounts of Vitamin A in their diet. So, what’s the next best option?
The simple answer is Beta-carotene (β-carotene). Beta-carotene can convert to Vitamin A in the body and is naturally occurring in food.
It is the most common of the carotenoid family, a natural yellow/orange food colorant. It can also be consumed as a supplement.
Intake of Beta-carotene varies widely throughout the world, but reports from the USA and UK report that average intakes are around 1-2 mg/d.
Fun Fact: Women in European countries including Germany, Austra, and Switzerland consume around 30% of their daily Vitamin A from Beta-carotene! (Source: Journal of Nutrition)
The Institute of Medicine does report that consuming a diet rich in β-carotene can meet daily Vitamin A requirements for those following a plant-based diet (Source: Journal of Nutrition).
Beta-carotene does get passed from mother to baby via breast milk, and helps to promote antioxidant defense for your baby.
Unlike Vitamin A, there are no specific daily requirements for Beta-carotene. Supplementation for mothers with poor diets may help to reduce illness but does not seem to affect illness in breastfed babies (Source: Pubmed).
If consumed in excessive amounts, Beta-carotene does not carry the same risk of birth defects like Vitamin A.
The recommended daily dose is around 3000 milligrams per day (which equals 5000 IU or 1500 microgram RAE equivalents).
Supplementation is only advised if recommended by a medical professional, as supplements are not regulated by the FDA.
Some medications can inhibit the absorption of fat-soluble vitamins, so in some instances, a supplement may be beneficial (Source: OSU).
One interesting side effect of consuming too much Beta-carotene is that it can actually turn the skin a yellow-orange hue, thanks to the concentrated pigment of the carotenoid.
This will usually show up first on the palms of the hands and the foot pads.
Food Sources of Beta-Carotene During Pregnancy
Looking to supplement your plant-based diet to meet your daily Vitamin A requirements?
Here is a list of foods rich in Beta-carotene that you can eat during pregnancy (and even if you aren’t currently pregnant).
- Carrots (raw, cooked, juiced); 5.1-22 milligrams per serving (1 medium raw carrot, 1 cup cooked carrots, 8 oz carrot juice)
- Pumpkin (canned); 17 milligrams per 1 cup serving
- Spinach; 13.8 milligrams per 1 cup cooked
- Sweet potato (baked); 13.1 milligrams per medium potato
- Collard Greens; 11.6 milligrams per 1 cup cooked
- Kale; 11.5 milligrams per 1 cup cooked
- Turnip Greens; 10.6 milligrams per 1 cup cooked
- Winter Squash (spaghetti, acorn, butternut, etc); 5.7 milligrams per 1 cup cooked/roasted
- Dandelion Greens; 4.1 milligrams per 1 cup raw
- Cantaloupe; 3.2 milligrams per 1 cup fruit
In conclusion, during pregnancy, it’s important to eat a well-rounded diet, rich in a wide variety of foods.
Vitamin A deficiency will likely not pose a risk, and as long as you are not consuming excessive amounts of Vitamin A from food or supplementation, it shouldn’t pose any problem for you during pregnancy.
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