The three natural steroids are: estradiol, testosterone, and progesterone.
The three synthetic hormones are: the estrogen compound zeranol, the androgen trenbolone acetate, and progestin melengestrol acetate.
They are typically used in combinations. Measurable levels of all the above growth-promoting hormones are found in the muscle, fat, liver, kidneys and other organ meats that we ingest during dinner time. The U.S. Food and Drug Administration (FDA) has set "acceptable daily intakes" (ADIs) for these animal drugs.
The ADIs are based on traditional toxicity testing methods and do not reflect the capacity of these drugs, which are potent endocrine disruptors, to alter fetal and childhood development.
According to Swan et al. (2007) - "...the possible effects on human populations exposed to residues of anabolic sex hormones through meat consumption have never, to our knowledge, been studied. Theoretically, the fetus and the prepubertal child are particularly sensitive to exposure to sex steroids..."
This gap of knowledge is remarkable, given that every beef-eating person for over 50 years has been exposed to these hormones on a regular basis.
The lack of human data on the safety of anabolic steroids in meat production prompted us to analyze mother's beef consumption while pregnant in relation to her son's semen parameters in a large multicenter pregnancy cohort study, the Study for Future Families (SFF) - reported Swan et al. (2007)
Researchers divided pregnant women into 2 groups: a high beef consumption group (more than seven beef meals per week), and a low beef consumption group (fewer than seven beef meals per week).
After the male babies were born and reached a stage where they can produce sperm, the scientists compared the sperm concentrations and quality among the men born to women in the high and low beef consumption groups.
Of the 773 men who provided semen samples, 387 were from mothers from the high beef consumption group, and 386 were from mothers from the low beef consumption group. The scientists found that:
Sperm concentration (volume) was 24.3 percent higher in the sons of mothers in the "low" beef consumption group.
Almost 18 percent of the sons born to women in the high beef consumption group had sperm concentrations even below the World Health Organization threshold for subfertility - about three-times more than in the sons of women in the low consumption group.
By the way, these men who were born to women in the high beef consumption group now have to have children of their own. So, who will be the problem, their wives not being able to get pregnant or men's low sperm concentration?
Mother's beef consumption may be related to other lifestyle factors. The researchers examined several maternal variables in relation to her beef consumption, such as: smoking, employment outside the home and parity.
However, they saw little or no association of these factors with her beef, but cannot rule out the role of other factors on which they had no data. Of these factors, mothers' smoking while pregnant is the only one previously related to the sonís semen quality (Jensen et al., 2004).
While they did not see an association with maternal smoking, the prevalence of smoking in the U.S. population was somewhat lower than in the European population in which this association was reported.
The authors of this study concluded that: "These findings suggest that maternal beef consumption is associated with lower sperm concentration and possible subfertility, associations that may be related to the presence of anabolic steroids and other xenobiotics in beef."
This study lends urgency to the long-recognized need for the FDA to reconsider the acceptable daily intakes of hormones used to promote growth in beef feedlots. This reassessment will, in all likelihood, be resisted by the animal drug and beef industries, and once begun, will take many years to be carried out.
Meantime, how do you protect your newborns and give them better future as far as ability for them to have kids too?
Very simple. By eating organic beef (or avoiding red meat altogether), mothers can avoid growth hormones, reducing the risk of developmental problems in their sons.
You can click here with your right mouse button to download and read the entire report from the study.