Vitamin A is vital for normal cellular function, including those involved in eyesight, reproductive functions, and normal development. But when people talk about “vitamin A”, they’re not always talking about the same thing. “Vitamin A” is a term that is used to refer to:
・ Retinyl esters
Both Carotene and Beta-Carotene (found in abundance in sweet potatoes, carrots, cantaloupe, apricots, peaches, and sweet peppers, to name but a few sources) have not been linked to any problems regarding vitamin A toxicity, so they’re off the hook. It’s the vitamin A you find in high-potency supplements that you have to keep your eye on. Some of those little capsules contain as much as 25,000 IU – well above the daily recommended allowance of a maximum of 8,000 IU/day as established by the FDA and plenty enough to cause any number of birth defects and deformities.
Many North Americans are getting far more vitamin A than they suspected: the active ingredient in acne medications such as Retin-A and Accutane or any skin treatment containing Retinoic Acid or Retinol is vitamin A and it’s absorbed through the skin. This includes many over-the-counter creams that promise to “brighten your complexion” or “ease those laugh lines” or “minimize fine wrinkles”.
It’s not just the baby that’s at risk: hyper dosing vitamin A will eventually have toxic effects on your entire central nervous system, your liver, your skin, and your bones. Taken during pregnancy, it can result in the baby being born missing part of its brain (called “anencephaly”), cleft lip, cleft palate, abnormal shortness of the lower jaw (“brachygnathia”), and various eye defects.
In the mid-60s, researchers took a look at synthetic versions of vitamin A using hamsters and found that while they at first appeared to show promise since they were minimally bio accumulative (they didn’t build up much in body tissues), they resulted in nearly 70 different documented birth defects as they affects almost every form of tissue and organ in the developing fetus. The timing of the overdose impacted the type of defect that resulted: at the earliest stage of pregnancy, the deformities were of the head, sensory organs, and the cardiovascular system while later on in the pregnancy, the impact was on the limbs, genitals, and urinary tract. Other reports showed that hypervitaminosis A impacted the mental and behavioral functioning of rats exposed during gestation.
For pregnant humans, the recommended dietary allowance is 3,300 IU of retinol or retinyl esters or 5,000 U in an average North American diet containing a blend of retinol and carotene (Food and Nutrition Board, 1980) (Table 2). The average diet is already very high in vitamin A so it’s recommended that pregnant women consult their attending physician or a qualified nutritionist to have their diet evaluated before adding a vitamin A supplement.
For more information on Vitamin A use while your pregnant, visit http://teratology.org/pubs/vitamina.htm