Yes, any thing that doesn't provide you with the necessary elements to survive like air food and water, take energy rather than contribute to it. Anything we do takes energy, even breathing. That's why we need food and water; to give us energy to function and survive.

f100_sup, you need to find another doctor. I can't believe any doctor would tell someone to start smoking. I don't believe you.

Smoking interferes with the normal function of your lungs. When you coat your lungs with tar and nicotine, when you develop small pockets in your lungs (emphysema), and when you destroy the cilia lining your bronchii, yes indeed.

It DOES deplete their endurance, BUT in MY case, it helps me stay alive as it helps with LOW blood pressure.

(I restarted smoking on Doctor's orders!!)

Yes it turns them into a "Puff"

yeah of course

ya absolutely.........