Health & Medicine questions
28 fact-checked questions — tap any to predict the answer, then read why.
- Why does chronic disease accelerate aging unevenly across different biological systems?
- Why do water-resistant sunscreens list 40 or 80 minutes, not 'waterproof'?
- Why doesn't SPF makeup count as one-and-done sun armor?
- Why can using too little sunscreen make the label SPF unreliable?
- SPF tests sunburn, and water-resistant tests wet use. What closes the UVA gap?
- Why can't SPF 15 simply mean '15 hours before you burn'?
- Why does SPF 50 beat SPF 30 by only about 1 percentage point?
- SPF 30 sounds like '30 units of strength.' What does it really say?
- How do painkillers work?
- Why do fevers help fight infections?
- Why does sunscreen protect skin?
- Why do we feel nauseous when dizzy?
- Why does our body reject transplanted organs?
- Why do bones heal after breaking?
- Why do we get allergies?
- Why does stretching reduce muscle soreness?
- Why do antibiotics not work on viruses?
- Why do we get headaches?
- Why does sunburn hurt?
- Why do some people need glasses?
- Why do ears pop on airplanes?
- Why does skin heal after wounds?
- Why do we need to brush teeth?
- Why do vaccines prevent diseases?
- Why does ice reduce swelling?
- Why do we get fevers when sick?
- Why do bruises change colors?
- Why do cuts bleed then stop?