this thread is a trip ..... scientifically most thc is absorbed in the first 3 seconds .. wait about 3-4 seconds more, you've absorbed all the thc your lungs will uptake, then you're just depriving oxygen and hurting your brain and lungs. ....... and don't forget ... whether you hold it in for 3 or 30 seconds ...you're still exhaling smoke that still contains about 25 percent thc. You need to breathe in order to get some fresh capillaries in the lungs to absorb the rest .........unless you can figure out a way to exchange oxygen through your lungs without breathing ......... holding your hit in longer than 5-8 seconds is a waste ................ i usually hold for about two or three. I'm not trying to choke my way through my buds... i want a nice inhale exhale everytime with the least amount of coughing involved.......... yall holding for holding as long as you can ..... just silly. save your brain cells ....your gonna need them if you think that holding that long is going to do anything but make you lightheaded.