Originally Posted by FXjohn
I don't buy that for a minute.
I wasn't selling. My advice is free to all. I can't speak for the diuretic affects of coffee(tho' I can attest that it make me piss a lot more). BUT my statement was the reduction of blood flow. Caffeine is a well-known cerebral vasoconstrictor. This is why migraine sufferers drink small amts. of coffee at the onset of a headache....to reduce the flow of blood in their head. Seems to me that this can only reduce blood flow to the fingers. Thus making them colder.
Using myself as an experiment. Today I didn't drink coffee before my ride, fingers were not cold. I drank coffee when I got to work and had to pee a lot. Thus coffee is a vasoconstrictor and a diuretic. I know more studies are needed but it worked for me.
Whether coffee is a diuretic or not does not affect the morning commute. I don't think I get hypothermic nor dehydrated on a 10 mile commute. Charlie