The average studies of cellphones and brain cancer have studied people who have used cellphones for five years or less. Sometimes eight years. Every study that has actually examined people who have used phones for 10 years or more, and is well designed, finds a 50 percent to an 800 percent increased risk. So that is why the Israelis, the Finnish, the French governments have all issued warnings.

You can do something really radical, which is turn your phone off and reclaim your private life.

We know that drugs, sex and rock and roll stimulates something called dopamine in the brain. So do videogames. Dopamine is something that we crave.

Say no to being on-call 24/7 unless you are an emergency responder. Use a speakerphone, use a headset.

There's an increase in serious weight disorders from cellphone use. And people who don't sleep have serious other consequences for their health that can be associated with it. There may be as well increases in problems with their memory. And all of those things are not as sexy and don't demand as much attention as cancer, but they can be very, very important from a public health point of view.

In particular, recently Belgium has banned the sale of a cellphone to a 7-year-old. Turkey has banned ads and advertising to children. So has France for children under 12. India has bans in certain areas. In Bangalore, you cannot sell a cellphone to someone younger than 16. So in different parts of the world, they've taken different steps.

The whole idea of what is evidence for causation in epidemiology cannot be separated from tTindustry understood that if they could raise doubt about how you could conclude something caused cancer, that they put so much effort into getting so many receptive public health authorities to say, "Well, causation requires that these five things be met." So that is, in fact, nonsense.