I would put something together on medicine and self-diagnsosis, meaning the symptom you can have that should alarm your - or not. Most young people are so dependent on Dr. mom that in adulthood they often react wrongly to something new that crops up.
For example, the first time I had an aural migraine I spent an hour wondering if I'd been zapped by a laser pointer from a passing car or ate poisonous sushi (aural migraines have a wildly predictable pattern of visual distortion that affects both eyes). The second time one occured I spent $500 or so and several hours in the ER, thinking I was about to die from some bizarre blood poisoning, to find out I had a headache (applause). The girl who billed me said that on her first aural migraine she pulled over on the side of the road and in a complete panic (she thought she was going blind) called her eye doctor.
There are a host of other symptoms you can experience that nobody warns you about, and this board is filled with people who experience all sorts of things.
Some more examples:
My downstairs housemate has tons of college-age friends. One spent a half-hour asking me "confidential" personal questions about how he no longer had regular poops, just constant and recurring watery diarrhea. I explained to him how drinking a fifth of whisky a day does that, the role of leutenizing hormones in large intestine water uptake, and how college kids have called it "the runs" at least since the 1700 hundreds. He asked what to do and I suggested drinking more water and less whisky, as nothing else is really going to return him to normal. Now he's doing fine and is sober way more often.
Another of my downstairs housemate's friends dropped out of the Univ. of South Carolina for a week because he had become terrified. He'd had a panic attack (his first one) while snorting cocaine, thinking his heart was about to explode, and as he related the horrifying symptoms I would finish his sentences for him, and elaborate on them (not that I've ever done drugs, but I am familiar with panic attacks since the age of about 30). He was amazed, thinking he must be the first person who had ever had one. I told him what was going on in his brain, reassured him that this is extremely common, and told him to discuss it with his doctor.
Over this past Memorial Day my housemate went to the lake to party. I suggested he take some road flares that I'd given him. While so drunk he doesn't actual remember the events, he used them to provide illumination as he searched for firewood. Fortunately the incendiary compounds of phosphorus and magnesium cauterized the wound, so the next day's first aid of biting off the blister and sucking on the ooze didn't result in a raging infection. But that's just a side note. He partied so hard that he was still throwing up three days later and his acid levels were through the roof. Only today did he manage to eat real food.
These symptoms are common and basic, yet none of his peer group seems capable of offering informed advice about even basic 1800's party knowledge. Worse are the housemates who didn't know that people with a family history of schizophrenia shouldn't smoke enormous amounts of weed after they've been having visual and auditory hallucinations, the one's who didn't know that an infected wound sending bright red streaks up her veins was a very bad thing, and the neighbor who didn't know that a Florida fire-ant mound was a very bad place to have sex on spring break.
I haven't even touched on diabetes, heart disease, kidney failure, dehydration, liver failure, breast cancer, epilepsy, Bell's palsy (had that), irritable bowel syndrome, and countless other maladies that many students will encounter either directly or indirectly, but in retrospect every person affected probably wonders why it took three months and a Google search to tell them what they should've been made aware of in high school.