|MadSci Network: Medicine|
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
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