Peter Attia· MD
Turns out there are speculations that decaf coffee can have as much as 15 to 30% of the caffeine that regular coffee has I haven't found that reference I've dug I've tried to find one that will show that I haven't found exactly that But there are some data from 2006 that were published saying that you know 15-ish% and but then again more recent data have shown that Starbucks I think says that their 12 ounce has 155 milligs of caffeine but outside laboratory testing found like 310 something like that So when you're decaffeinating coffee that it's much more caffeinated than you started with