There are actually two different kinds of food-borne intestinal distress, the first of which sets in a few hours after a meal and may leave you nauseous (or even running for the bathroom). This one, believe it or not, is actually the milder case, and your body typically finds relief after evacuating the offending meal.
The other sort of food poisoning – what I like to refer to as “real” food poisoning – doesn’t arrive until between 12-24 hours (at the earliest) after the bad food passed your lips, and it could leave you praying for death on your bathroom floor for up to 24 hours after that.
Yeah. Did it once, do not ever wish to repeat.
The CDC lists four common culprits of food-borne illness: norovirus, Salmonella enterica, Clostridium perfringens, and Campylobacter jejuni. The time from ingestion to symptoms varies from (at least) 6 hours with Salmonella to up to 2 days with Campylobacter.
So, even if your last meal is the one coming up (and the one your mind will associate with the terribleness for years to come), it’s probably not the culprit in the worst cases of food-borne nastiness.
Sadly, there’s nothing much to do besides cry, call your mom, and camp out in the bathroom until its over. You should try to keep down liquids (ha!) and call a doctor if you haven’t been able to for over 24 hours.
There’s not a whole lot you can do to prevent nasty microbes from arriving with your dinner in a restaurant (or a hotdog at a ballpark, in my case), but at home, make sure to wash your hands and prep surfaces regularly, avoid contamination between raw and cooked foods, cook to recommended internal temperatures, and yeah, did I mention washing your hands?
Take extra care with foods like shellfish, red meat, poultry, eggs, and fresh fruits and vegetables, as these are at the highest risk for carrying pathogens.
Wash your lettuce and berries, people. Trust me (and the CDC) on this one.