^ Yes
WEIGHT = MASS x ACCELERATION
Yes, that means we are all accelerating towards the center of the planet, because of gravity, people in space don't have to worry about gravity, but they do have to worry about acceleration.
Getting into a car and accelerating changes your weight, and pushes you into your seat, decelerating does the same with the seatbelt. So in other words, people who gain or loose weight too quickly will die.
This is why Weight Watchers never recommend eating brick walls.