How long can a person live without food and water or air?

The increased acidity of the stomach can produce dry heaves. Blood thickens, increasing heart rate. Another unpleasant result of dehydration is a swollen tongue. While your tongue swells, your eyes and brain shrink. As the brain shrinks, the membrane or meninges pulls away from the bones of the skull, potentially tearing. Expect a horrible headache. Dehydration eventually leads to hallucinations, seizures, and a coma. Death can result from liver failure, kidney failure, or cardiac arrest.