It does, but like everything absorbed through the digestive system it gets extensive first-pass metabolism through the liver before entering the rest of the circulatory system.
Oral estrogen comes in 2mg tablets, but this results a few in µg of estrogen circulating. Estrogen also comes in transdermal patches where one 100µg patch will last three days for approximately the same dose as 4mg of oral ostrogen daily.
"Estrogens are also contained in meat and eggs, but the major sources are milk and dairy products. By drinking a glass of milk, a child’s intake of estradiol is 4000 times the intake of xenoestrogens, in terms of hormone activity. See, modern genetically-improved dairy cows can lactate throughout their pregnancy; the problem is that that’s when the estrogen levels can jump as much as 30-fold.
Though cheese intake has been associated with lower sperm concentration, dairy food intake has also been associated with abnormal sperm shape and movement, so this suggests that dairy intake may be implicated in direct testicular damage, and not just a potential suppression of sperm production due to the estrogen."
"Estrogen hormones can be thousands of times more estrogenic than typical endocrine-disrupting chemicals. Dietary exposure to natural sex steroids (in meat, dairy, and eggs) is “therefore highly relevant in the discussion of the impact of estrogens on human development and health.” And chicken estrogen is identical to human estrogen—they’re the same molecule."
"Foods of animal origin in general naturally contain hormones, but cow’s milk may be of particular concern. The hormones naturally found in even organic cow’s milk may be playing a role in the studies that found a relationship between milk and dairy products with human illnesses, such as teenagers’ acne; prostate, breast, ovarian, and uterine cancers, many chronic diseases that are common in Western societies, as well as male reproductive disorders. Milk consumption has even been associated with an increased risk of early puberty in girls, and endometrial cancer in postmenopausal women, but hormonal levels in food could be particularly dangerous in the case of vulnerable populations, such as young children or pregnant women. "
"Pregnant cows excrete significantly higher levels of sex steroids into their milk than non-pregnant cows. The subsequent consumption of such dairy products may mean an unnecessary risk, but one that could be easily avoided. But it’s not just dairy. Although dairy products are an important source of hormones, other products of animal origin must be considered as well.
All edible tissues of animal origin contain estrogen. This may explain why, in a study of over a thousand women eating plant-based diets, vegan women have a twinning rate that is one fifth that of vegetarians and omnivores."
