Humans have a seemingly infinite capacity to worry. The problem is, with a near-infinite supply of things to worry about, we wind up fretting over problems that don't exist. One of these non-issues that keeps popping up is the idea that cell phones cause brain cancer. Despite there being study after study of cell-phone radiation showing no link at all to brain damage, and despite there being no physical way a cell phone can cause brain damage, people still worry about it. If you run across someone who believes this, now you have a place to send them: a video of a talk at a National Capitol Area Skeptics meeting, where Professor Christopher Davis (from the University of Maryland's Department of Electrical and Computer Engineering) totally destroys these claims. It's a full-length talk, but it's all online. Here's part 1: The rest of it is online as well: Part 2, Part 3, Part 4, and Part 5. If you want the bullet points, they're not too hard to remember: 1) People fret when they hear the word radiation, but there are lots of kinds of radiation, most of which is harmless. 2) One type of radiation is plain ol' light. Radio waves are radiation. Microwaves are radiation. These types of radiation are essentially harmless. 3) The type of radiation cell phones emit is on the borderline between radio and microwave light. 4) Not only is the type of radiation from cell phones harmless, the amount of it is too small to hurt us. Regulations set the power of cell phones far, far lower than levels known to be even borderline noticeable. 5) There have been many careful studies looking at any connection between cell phones and health risks. None has been found. Note: this means direct risk, not things like phoning while driving, while using a buzz saw, while running from zombies, and so on. 6) Cell phone use has exploded worldwide, with hundreds of millions of users. Yet the rate of brain cancer detection has been steady for years. If there were even a tiny connection, we'd see a dramatic increase in brain disease. We don't. 7) Therefore, cell phones don't cause cancer or brain damage. Can you hear me now?