The Corpus Callosum

(This is a public health announcement for women and men.)

News agencies are, appropriately, reporting on the finding that the
average levels of folate in American women are falling.  (e.g.
href="http://www.usatoday.com/news/health/2007-01-04-folates_x.htm?csp=34">Folate
levels in young American women fall, could lead to rise in birth defects)
The media are doing a pretty good job of putting this in context.
 I am happy to see that the subject is getting as much
attention as it is.  But it is so important,
that I want to add some additional background information, in order to
reinforce this crucial public health issue.  For one thing,
the news reports seem to be aimed at raising the alarm for women.
 But men need to pay attention, too.


The history is as follows: Once it was established that folate can help
prevent birth defects, supplementation of grain products was mandated
in the USA.  This is detailed in an href="http://www.cdc.gov/mmwr/preview/mmwrhtml/mm4942a4.htm">MMWR
review from October 27, 2000:

In 1992, the U.S. Public Health Service (PHS)
recommended that women of child-bearing age increase consumption of the
vitamin folic acid to reduce spina bifida and anencephaly (neural tube
defects [NTD]) cases (1). Since then, national efforts have been
implemented to increase the use of dietary supplements containing folic
acid (2). In 1996, the U.S. Food and Drug Administration (FDA) mandated
that all enriched cereal grain products be fortified with folic acid
(3). To assess levels of folic acid among childbearing-aged women, CDC
compared serum and red blood cell (RBC) folate concentrations for
childbearing-aged women who participated in the 1999 National Health
and Nutrition Examination Survey (NHANES 1999) to childbearing-aged
women who participated in the Third National Health and Nutrition
Examination Survey (NHANES III, 1988–1994). The findings indicate
substantial increases in serum and RBC folate concentrations among
women of childbearing age.

Note:
and are two slightly different forms of the same
thing.  The distinction between the two is not important in
this context.

Once public education was undertaken in earnest, and manufacturers were
required to put folic acid in enriched cereals, there were href="http://www.emedicinehealth.com/spina_bifida/article_em.htm">measurable
benefits:

A rigorous program of public education and
fortification of popular foods with folic acid in the United States has
decreased the rate of neural tube defects by about 20% in just a few
years.

is the most common type of a class of birth defects,
known collectively as neural tube defects.  There is a href="http://www.wisc.edu/ansci_repro/misc/project_websites_06/tuesday/neural_tube/dreamweaver_folate.htm">good
review of this topic at the University of Wisconsin’s site,
if you want to know more about the types of neural tube defects, and
the relationship to folate.  (There are some unpleasant
pictures of the site.)  There is a less technical, more
consumer-oriented review href="http://www.pueblo.gsa.gov/cic_text/health/folate/796_fol.html">here.

The are two possible reasons for the improvement in levels of folate in
women.  Part of it could have been due to the public education
efforts; part of it could have been due to increased governmental
intrusion into business practices.  But survey data show that
the the public education effort did not change people’s behavior very
much, so it was probably due to the regulatory interventions.

But now, we hear that the progress is being lost.  The CDC
publication, Morbidity and Mortality Weekly Review (MMWR) href="http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5551a2.htm">reported
yesterday:

During 2001–2002 and 2003–2004, median (50th
percentile) serum folate concentrations among women aged 15–44 years
were 11.4 ng/mL and 10.6 ng/mL, respectively. Thus, a statistically
significant 16% decline was observed from 1999–2000 (12.6 ng/mL)
through 2003–2004 based on comparison of geometric means
(p<0.001) (Table 1). Similarly, RBC folate concentrations
decreased 8%, from 255 ng/mL during 1999–2000 to 235 ng/mL during
2003–2004 (p=0.028).

The authors state that it is not clear why this is happening, but they
have several hypotheses.  I won’t go into that here; it is all
rather technical.  Part of it may be a trend toward
low-carbohydrate diets, because the mandated supplements are added to
grain products.  There is also some evidence that
manufacturers, in some cases, are not adding as much folic acid as they
used to. The evidence they cited is not strong, so I would not yet
begin to condemn the manufacturers.  But would it not be
terribly disturbing, if it turned out that there were more babies born
with spina bifida, because some companies wanted to save a few pennies?
 

Anyway, the bottom line is this:  Even though the data show
that public education does not help much, I am going to try to
reinforce the message: all women of childbearing
potential should make sure they are getting enough folate.
 This recommendation is not restricted to
those who are trying to get pregnant.   href="http://www.guttmacher.org/pubs/fb_induced_abortion.html">Nearly
half of pregnancies in the USA are unintended.  Get
that?  In case you don’t, let me emphasize the point: all
women who are capable of having children need to pay attention to this.
 I do not care if you have taken a virginity pledge.
 Those don’t work, anyway.  I don’t care if you are
sure you would get an abortion.  People change their minds.
 Basically, there is no excuse for not attending to this.

Even males, who are sexually active with women who
could get pregnant, need to pay attention to this.  For the
men (and boys, I guess) out there: it does not matter whether you
intend for pregnancy to occur.  It is your responsibility to
understand that pregnancy might occur, and you
better be ready to face the consequences.  

Men cannot control the health-related behaviors of
their sexual partners,but, they can exert a positive influence.
 Be responsible, guys.