Re: Does meat we eat contain measurable hormones such as estrogen?

There is considerable interest in the hormone content of foods, with the 
phytoestrogens (plant compounds) being in greater supply and of more 
current interest than compounds found in meat.  The Environmental 
Protection Agency is developing a program to track the hormone content of 
the food supply.  You can read their report to congress at  http://www.epa.gov/scipoly/oscpendo/reporttocongress0800.pdf.  

Numerous studies done during the past 15 or 20 years have documented 
differences in excretion of estrogen-like substances by vegetarians and 
non-vegetarians which indicates that diet does influence the intake of 
these compounds.  The main thing this tells us is that diet does 
contribute hormone activity, but understanding the true impact of these 
observations will require much further study.  Growth hormone could be 
given to animals to increase their growth, but the amount in the muscle of 
the meat would be miniscule, it is estimated to be much, much less than 
the amount of your own growth hormone that leaks into your saliva and is 
swallowed with meat   Also growth hormone is so expensive it would not be 
used in animal husbandry.

A 1981 study found that vegetarians excrete 2 to 3 times more estrogens in 
feces than do omnivores (meat eaters) but that omnivores have about 50% 
higher mean plasma level of unconjugated estrone and estradiol (hormone 
derivaties) than do vegetarians.  Thus the question of whether meat or soy 
and other plant sources of estrogen activity have more impact on health 
remains to be known. A recent article in the Journal of Food Composition 
and Analysis offers a look at the current status on the analysis of plant 
lignans (compounds with both estrogenic and antiestrogenic properties).

I have more questions than answers to give you.  Your observations are 
important, but I suggest it will take many years before we will the data 
needed to act on your suppositions.

I hope this is helpful.  You can find many controversial documents on the 
internet by searching for “endocrine disrupters”.

Reference:  
Meagher, LP and GR Beecher.  Assessmentof data on the lignan content of 
foods.  J Food Composition and Analysis, 13:935-947, 2000.


Sincerely,

Phyllis Stumbo
University of Iowa