If you have not already, please check out Dr. Paul's video discussion on this topic, where he debunks many of the myths surrounding Vitamin A toxicity. In the meantime, I'll discuss acute toxicity, chronic toxicity, and pregnancy regarding these concerns.
Including liver can be very beneficial during pregnancy. Not only is this vitamin essential in fetal development, but a newborn can only receive this vitamin from breast milk. It's well known that Vitamin A is critical for a child's respiratory tract development and function. Many would argue that Vitamin A recommendations and pregnancy are too low, and the requirement increases during this time to supply adequate amounts to both the mother and child for optimal health and development.
The totality of concerns for Vitamin A in pregnancy can be traced back to a study in 1995 led by Dr. Rothman of Boston University. They followed almost 23,000 women who consumed 10,000 IU or more from supplements or food sources (mainly from fortified breakfast cereals or processed food) during their first trimester and noted an increase in birth defects.
The caveat here is that the generally accepted rate of birth defects in women is 3-4%, and we saw only a rate of 1.5-3% in these women (this was not revealed in this particular study). Essentially, no significant increase in birth defects was seen with Vitamin A supplementation or food consumption.
Now that we know where the concerns have originated from, let's look at the overwhelming research that conflicts:
A 1990 study on 25,000 births in Spain noted that doses of vitamin A over 40,000 IU daily carried a 2.7-fold higher risk of birth defects. Amounts of vitamin A up to 20,000 IU or between 20,000 and 40,000 IU both had a 50 percent lower risk of birth defects compared to no supplementation.
A 1996 study of 522,601 births found that the children of women supplementing with at least 10,000 IU of vitamin A alongside a multivitamin had a lower risk of birth defects than those of women who did not supplement. However, the association could not be distinguished from the effect of chance.
A 1997 study of 1,508 births found no relationship between birth defects and using vitamin A supplements, including organ meat such as liver or fortified breakfast cereals.
A 1999 prospective study of 423 mothers who consumed between 10,000 and 300,000 IU of vitamin A in the first trimester compared to a group that did not supplement with vitamin A found no evidence of an increased risk of major malformations with increasing doses. The median dose was 50,000 IU. The group as a whole had a 50 percent lower risk of major malformations than those who did not supplement. There were no significant malformations in offspring born to mothers consuming more than 50,000 IU.
As Chris Masterjohn, Ph.D., stated in an article from Weston A. Price, "The preponderance of the evidence clearly favors the view that 20,000-25,000 IU of vitamin A during pregnancy is safe and may even reduce the risk of birth defects".
In conclusion, megadoses of Vitamin A in supplemental or food form are never suggested. However, we believe consuming 0.5-1 oz of fresh beef liver daily will be beneficial. The liver is a rich source of bioavailable zinc, selenium, B12, folate, riboflavin, and many others that are crucial for metabolism, immune function, and fetal development. Our ancestors also treasured it.
Consuming 1-2 oz of organs is totally safe and healthy during pregnancy. This will allow for a robust intake of valuable nutrients and still allow you to be below the 10,000 IU Vitamin A threshold broadly recommended by the medical establishment.
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