Allow me to go a bit off the topic of heart disease for a brief, but important, digression.
I feel rather strongly about this. And, while it doesn't relate directly to heart disease, heart disease prevention or cholesterol, it does indeed interface with these issues at several levels.
In my view:
Human women should receive human hormones.
Perhaps that sounds peculiar. Let me explain.
The medical literature on hormonal replacement in human females is filled with mostly negative reports on the effects of horse estrogens on human females - increased endometrial and breast cancer risk, slightly increased risk for heart attack in women with initial use. The large, well-funded studies, the Women's Health initiative (WHI) and The Heart and Estrogen/progestin Replacement Study (HERS), both used Premarin® brand of "horse equine estrogens" - horse estrogens, and synthetic progesterone, "progestins."
The principal females hormones in humans are the three estrogens, estriol, estradiol, and estrone, and progesterone.
Premarin®, isolated from pregnant mares' urine, is a complex mix of at least 10 different estrogen-like substances: estrone, 17beta-estradiol, 17alpha-estradiol, and the ring B unsaturated estrogens: equilin, 17beta-dihydroequilin, 17alpha- dihydroequilin, equilenin, 17beta-dihydroequilenin, 17alpha- dihydroequilenin, and delta-8-estrone. Likewise, the most commonly prescribed synthetic progestin is medroxyprogesterone acetate.
Why use horse estrogens or synthetic progestins in human females? They must be superior! Otherwise, why would non-human preparations be used in humans?
In fact, there are data showing that horse estrogens behave quite differently than the natural panel of human estrogens, particularly in blood clotting (horse estrogens promote blood clotting much more than human estrogens), cancer-triggering and inflammatory effects.
Likewise, progestins exert fluid-retaining, depressive, inflammation-inducing, triglyceride-raising effects not shared by its natural human progesterone counterpart.
Then why would human women receive non-human, horse estrogens and synthetic progestins?
If a male has a low testosterone, would we use pig, alligator, horse, or hamster testosterone? Or would he receive human testosterone? He receives human testosterone, of course. Why would human women be any different?
I can think of no other reason than patent protection and profits. Natural human estrogens and progesterone are widely available and inexpensive (though Wyeth has lobbied the FDA to prevent consumers from obtaining these preparations and has, sadly, enjoyed some success; the FDA now prohibits the use of the term "bio-identical," and there is a continued push to ban the availability of these hormones altogether).
Unfortunately, non patent-protectable products, like human estrogen and progesterone, don't command the profits like patent-protectable products and expensive research is less likely to be conducted.