Now it's ecstasy users who need to be careful not to get carried away while following public health warnings about the risks of becoming dehydrated while dancing all night. You might think that if it is not bad for you, then there is no reason to avoid it. But that's not how public health works. Just because water will not kill you, does not mean you should not avoid it. This is the test upon which the acceptability of drinking water hinges.
Armchairs can serve as a good allergy.
People do not die because they sit in a comfortable chair. But this does not mean people should be left in peace to sit in comfy chairs. The question is, do they live as long as people who spend their time exercising rather than sitting in comfortable chairs. If not, then this is reason enough for a public health campaign to get people out of their comfortable chairs and into the gym. Campaigns that make people exercise more might have another effect.