Hi, folks
For those of you who wish to read the study for yourselves, here's a free
link to the entire article:
http://www.nature.com/ijo/journal/vaop/ncurrent/full/0803622a.html
A few quotes from the study marked by *, and my initialed comments:
*"Breastfed infants gain weight more slowly during the first year of life
than formula-fed infants, probably due to the natural limitations of
available energy supply."
MCV--Notice which is the standard of reference here. And maybe I'm
introducing bias that only exists in MY brain and not these researchers, but
the "slower" weight gain for bf babies is due to the natural limitations of
available energy supply"?? Does that sound like bf is somehow denying babies
the extra weight??
*"Participants are predominantly Caucasian white."
MCV--Obesity varies by ethnic origin so we are missing major pieces of the
puzzle.
*"Participants in the NHS II were asked in 1989 to report their height,
their current weight and their weight at age 18. Information on current
weight was updated on biennial questionnaires. Body mass index (BMI) was
calculated as weight divided by the square of height (kg/m2). The validity
of recalled weight at age 18 and self-reported current height was examined
among 118 participants of NHS II using records from physical examinations
conducted at college or nursing school entrance.17 The correlation between
recalled and measured past weight was 0.87 and between reported current
height and measured past height was 0.94. Mean BMI values were 21.6 kg/m2
for BMI calculated using recalled weight and were 22.1 kg/m2 using weight
from medical records; the correlation was 0.84. Overall, the validity of
recalled weight at 18 years of age and self-reported height appears to be
high among women in this cohort."
MCV--I am NOT an expert in statistical analysis, so help me out if I'm
misinterpreting. However.... If I understand this right the correlation on
these recalled data is 0.84--that would be on a scale of 0 (can't remember
anything right) to 1.0 (complete and total accurate recall). 0.84 leaves a
LOT of wiggle room--especially when you look at the better done obesity
studies where the effect of bf is seen to be fairly small, but still
significant. This much variation in recall could negate the amount of
difference that bf might confer.
*"NHS II participants were also asked to recall their body shape at ages 5
and 10 using a nine-level figure drawing (Figure 1) originally developed by
Stunkard.19 Must et al.20 evaluated the validity of remote recall of body
fatness among 181 participants in the Third Harvard Growth Study, a
Boston-area longitudinal study of physical and mental growth in children
that was conducted between 1922 and 1935.Height and weight were measured as
part of annual examinations during childhood and adolescence and were used
to calculate BMI in kilograms per meters squared (kg/m2). In 1988 and 1989,
when participants were between ages 71 and 76, they were interviewed again
and asked to recall their body fatness at ages 5, 10, 15 and 20, using the
same 9-level figure drawing as on the 1989 NHS II questionnaire. Pearson
correlations between recalled body fatness and BMI at approximately the same
ages were 0.60 for age 5, and 0.70 for age 10. Other studies had similar
findings,21, 22, 23 indicating that, although imperfect, these figure
drawings can provide useful information on body fatness at young ages."
MCV: Again, we are talking about recall of what people THOUGHT they looked
like at age 5. The correlation figures are 0.60 and 0.70--again, pretty low
for what is likely a relatively small difference. Heck, I find myself
startled when I see pictures of me TODAY that don't fit with my mental image
of how much I weigh!!
*"Information on infant feeding was coded as (1) having been breastfed for
at least 1 week vs having never been breastfed or breastfed for less than 1
week, (2) duration of any breastfeeding (1 week-3 months, 3-6 months, 6-9
months, 9-12 months, one year or more) and (3) duration of exclusive
breastfeeding (1 week-3 months, 3-6 months, 6 months or more). "
MCV: The time periods here that bother me the most (other than the first
grouping's def'n of having breastfed) is teh 3-6 month range. When you look
at starting solids, that range includes 2-3 months worth of TOO EARLY solids
for MOST babies.
As someone pointed out, I don't think comparing figures from 40 years ago to
today makes sense, given differences in formula, feeding practices, and the
general knowledge we have now about lifestyle affects on weight control.
I DO believe that breastfeeding confers some protection against obesity. I
DON'T think it is a HUGE protection but one of many undeniable benefits of
breastfeeding that exist as a package. And honestly, trying to research
whether breastfeeding can help fight obesity trends is nearly pointless.
Formula is not, cannot be, nutritionally comparable to breastfeeding. It is
an inferior product. Period. Now, perhaps IF a WELL DONE study (which would
be extremely hard to come by) showed that breastfeeding INCREASED the risk
of obesity significantly, then that would be news.
Okay, the choir can sit down now......
:-D
Melissa Vickers, IBCLC
(and author of the recently published LLLI pamphlet on Breastfeeding and
Obesity, and no, I don't gain financially from sales of this pamphlet!)
----- Original Message -----
From: "MR ROBERT W GUBALA" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Tuesday, April 24, 2007 1:04 PM
Subject: obesity
> Hi Melissa,
> Saw an article in our local paper today on a study
> of obesity ; that bfeeding makes no difference to
> obesity in adulthood.I typed in International Journal
> of Obesity on my search bar and was rewarded by being
> able to get this article free.Check it out ,look for
> "A Longitudinal Study of Infant Feeding and Obesity
> Throughout Life Course" by
> Michels KB ,April 24 ,2007 .I think there is too much
> recall, not only from the nurses studied but by the
> nurses mothers who were also questioned.I'm not sure
> if all the types of bf were lumped together.What's
> your take?? Judie Gubala
>
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