I don’t know how they measure it, but I used to stink despite showering twice a day. I had to put a lot perfume and deo. I always had the feeling that my bath towels were stinking. Until, one day I ran out of soap and used my head and shoulder as soap and also forgot to put deo. 24 hours later there were very litle sent that you had to be mm away from under arm to smell anything. Now I just use head and shoulders as my soap and shampoo. I only use deo if I’m going to do labour intensive movements/activities. My wife was shocked when I told her I havent used deo in over 6 months. Her only concerns is about safety, since I am using it daily. If any of you reading this are scientists let me know the risk of the daily usage.