On the Internet, you can find recipes for cooking human placenta and services to have the organ turned into pills.
Now, a paper by Buffalo researchers suggests ingesting parts of the afterbirth may offer benefits to human mothers and, perhaps, to non-mothers and males, as well.
Although most animals eat the placenta, Mark Kristal, the lead author, and his colleagues do not endorse that humans do it. Their main point is that the issue warrants study as a potential benefit for the development of new therapies.
For instance, the researchers from the University at Buffalo and Buffalo State College point out that the benefits of placenta ingestion by non-human mammals are significant, including an increase in mother-infant interaction and pain-reduction in the delivering mother.
Scientists need to identify the molecule or molecules that produce beneficial medicinal or behavioral effects and try to use them to design treatments, said Kristal, a University at Buffalo professor of psychology and neuroscience, whose work appears in the latest Ecology of Food and Nutrition journal.
The placenta is an organ that forms from maternal and embryonic tissue, and that attaches to the inside of the uterus and is connected to the fetus by the umbilical cord. It provides the fetus with nutrients, eliminates wastes, exchanges respiratory gases and secretes hormones important in pregnancy.
Kristal said it's not clear why humans, unlike most other mammals, don't eat the placenta, although research suggests there are evolutionary reasons.
"The fact that we humans don't ingest the placenta suggests that it was evolutionarily more beneficial not to do it. Maybe it is not 100 percent safe, so caution is necessary and our approach should be scientific," he said.
Interest among humans in placenta-eating dates mainly from the 1960s and the growth of the natural childbirth movement. There are claims made that ingesting the placenta raw, cooked or in pill form can give individuals more energy and increase happiness.
Kristal said there is no evidence that this is true and he cautions that anecdotal reports by people are unreliable and likely the result of a placebo effect.
"As with a lot of fads and alternative medicines, you need to keep the science in mind and not go by the urban legends and anecdotes. So far, there is no science to back up these claims," he said.