What's in a hamburger?

Well US ones anyway, as that's where the study was done. Not that I think Australian hamburgers would be much better. They analysed 8 fast food hamburgers scientifically. There's a lot of stuff that I don't understand that you can read at the link, but this end paragraph was gross:

Fast food hamburgers are comprised of little meat (median, 12.1%). Approximately half of their weight is made up of water. Unexpected tissue types found in some hamburgers included bone, cartilage, and plant material; no brain tissue was present. Sarcocystis parasites were discovered in 2 hamburgers. more

And what is this "Sarcocystis"? According to Wikipedia these parasites can cause the following:

In volunteer studies with infected beef symptoms appeared 3–6 hours after eating. These included anorexia, nausea, abdominal pain, distension, diarrhea, vomiting, dyspnoea and tachycardia. All symptoms were transient and lasted about 36 hours. In a second series symptoms - abdominal pain, distension, watery diarrhea and eosinophilia - appeared at 1 week and resolved after 3 weeks. 

Clinical cases have been associated with acute fever, myalgias, bronchospasm, pruritic rashes, lymphadenopathy, subcutaneous nodules associated with eosinophilia, elevated erythrocyte sedimentation rate and elevated creatinine kinase levels. Symptoms may last as long as five years. Segmental necrotizing enteritis has been reported on one occasion. more

I don't understand much of that but it doesn't sound good......