Inside Kodak, this was known as the "silver halide" strategy -named after the chemical compounds in its film.

Many causes of cancer are environmental, largely from tobacco, excessive sun exposure and workplace hazards such as chemical solvents and fumes. Avoidance is the best prevention strategy here.

I never drink coffee and I only occasionally drink caffeinated teas. While caffeine can be a temporary chemical solution to your drowsiness, I don't believe it is the best strategy overall.