Everyone can get sick... But how likely is that?

Today I had a typical health anxiety moment. After 20 years you'd think I would not fall for it anymore, but anxiety has so far always outsmarted me. 

I had slept poorly. I woke up a few times during the night, listening to me heart skipping and trying to calm myself down. In the morning I made tea and skimmed through the news. A headline caught my attention: a singer had passed away peacefully at the age of 56 of acute liver failure.

Hmm, a liver failure? What is that? Google told me three things

• symptoms of this life-threatening emergency (vague symptoms which I luckily didn't have)
• that 5-10 people in a million get it
• and that anyone can get an acute liver failure and it will kill if not treated immediately. 

Anxiety galore! I'm going to get it! I'm dying! Aaaaaargh! ... or am I?

Alright, yes, everyone can get it... BUT the chance is 0.001 - 0.0005 %. 

First of all, that 0.001 % chance is not the chance of me instantly dropping dead. It's the chance that I develop a condition, which requires treatment.   

Secondly, the odds are not evenly distributed. The 5-10 people of one million who get an acute liver failure likely had predisposing ailments or other contributing factors. They were already in higher risk than me, so the odds don't even apply to me. One of the wonders of statistics.

Thirdly, the odds are always calculated for a specific population. If those are the odds for the "average American", they already do not apply to me (a European). Lifestyle, genetics, diet, pollution, environment etc all affect those odds. 

Fourthly (is that a word?) the chance of actually dying of acute liver failure is much less than the 0.001 - 0.0005 %. 

So what do those odds really tell me? Honestly, the best description would be "it's really freaking unlikely that I would need to be hospitalized for acute liver failure."