In addition to the primary danger of cardiac arrest, there is good evidence to document that there is a very real risk of cumulative brain damage if the practice is repeated often enough. There are many documented additional dangers. Additionally, there are documented cases in which the recipient appeared to fully recover but was found dead several hours later. Most such deaths occur during solo play, however there are many documented cases of deaths that occurred during play with a partner. It should be noted that the presence of a partner does nothing to limit the primary danger, and does little or nothing to limit most of the secondary dangers.
Some people teach that choking can be safely done if pressure on the windpipe is avoided.
Their belief is that pressing on the arteries leading to the brain while avoiding pressure on the windpipe can safely cause unconsciousness. These bodies then cause vasodilation in the brain, thus there is not enough blood to perfuse the brain and the recipient loses consciousness. However, that's not the whole story. Unfortunately, a message is also sent to the main pacemaker of the heart, via the vagus nerve, to decrease the rate and force of the heartbeat. Most of the time, under strong vagal influence, the rate and force of the heartbeat decreases by one third.