While talking the food may get into the wind pipe, i.e, Trachea, which extends from larynx in the neck to bronchi in the thoracic cavity.
As a result, the wind pipe may get chocked and we may get hiccups. The process of respiration stops and at that time we are not able to breath.
It may also result in fatal and lead us to death. There are many such cases, where the a person died by getting the food being chocked in the trachea.
hope this helps..:)))