Love sushi? Much of the time it loves you back. High in protein and low in fat, what's not to like? But reports out of Japan have gastroenterologists serving up some new advice for sushi lovers: If you suddenly fall ill with stomach pain, cramps, vomiting, or diarrhea, make sure you tell your doctor what you had for dinner.

That's because raw fish can contain the larvae of a small parasite called Anisakis. It can't survive for long inside your body, but while it's there it can give you some serious digestive trouble, trouble that may cause your doctor to go looking for more ominous causes, like bowel obstruction or appendicitis. But since the treatment for Anisakis infection is usually fluids and bed rest, by telling your doctor you ate sushi for your last meal, you might be able to save yourself expensive or invasive tests and treatments.

As an aside, when fish has been commercially frozen, parasites are killed, so you're only likely to be at risk from infection if your sushi is very, very fresh.