Today a friend, with the best of intentions, gave me a lecture on why I should not be brushing my teeth with toothpaste containing fluoride, and why I should abandon using a cell phone altogether.
Her concern, on the topic of fluoride, was that fluoride can be toxic, and that certainly some of it is going to get into your system when you brush your teeth. Well, yes, but then anything in high enough doses is going to be toxic. Too much salt can be toxic, hell, too much water can be toxic. That doesn't mean it isn't beneficial in smaller doses.
Toothpaste is not intended to be eaten. My friend duly noted that there is a warning printed on toothpaste. Has anyone ever read the warning? I'll assume not and quote the one from my own personal tube. To wit: "Keep out of the reach of children under 6 years of age. If more than used for brushing is accidentally swallowed, get medical help or contact a Poison Control Center right away." Translation? Children under the age of 6 are stupid enough to try to eat an entire tube of toothpaste if they think it tastes good.
I have personally experienced seeing a child (age about 4) being brought into the emergency room for treatment from eating an entire jar of One-a-Day vitamins because he "thought they were candy." Result? Iron toxicity which killed the child.
If you stopped using every product that a child could potentially use to kill himself or someone else, you'd be left with ... actually, I can't think of anything a child couldn't use to kill himself or someone else. I'm amazed at the number of children who make it through the first few years of their lives given the hazards.
The next warning concerned microwave radiation coming from cell phones, and hadn't I heard about all the brain tumors growing in the shape of cell phone antennas?? Ummm ... no? I would say it was possible that I hadn't heard about them because I don't keep up with that stuff. However, I do keep up with that sort of stuff (once a scientist, always a scientist), and so decided to do some additional research on the topic.
As of this date, there are no credible studies proving a connection between use of cell phones and brain tumors. I did find some anecdotal evidence about such tumors, but the problem with anecdotal evidence is ... well, it's anecdotal.
If I may digress for a moment. I happen to believe in ghosts (yes, I'll wait until you stop laughing). I believe in them because I have seen them. So, does that stand as proof that ghosts exist? No, it stands as proof that I believe in them. Nothing more or less than that. Anecdotal evidence is simply proof that a particular person believed something, and passed that belief on to someone else. It stands for nothing as to the truth of idea itself.
What was interesting, was that the site link my friend gave me (for a product that is supposed to guard against the evil effects of microwave radiation), cites numerous articles, that do nothing more than illustrate that (1) there is a debate going on, (2) most of the scientific community believes there is no connection between use of cell phones and brain tumors, (3) that the critics disagree, not so much because they have any hard evidence, but just because they disagree.
So, why do I call that a con? Because the site panders to fear to sell a product that has no proven efficacy. That's how a con works, you see. The con artist works whatever angle will work best on any particular mark. Sometimes it's fear, however, greed, sex, and even altruistic beliefs can be used. Whatever the con chooses, it will be something that the mark will have a difficult, if not impossible, time turning his or her back on and walking away.
In the case of this site (which I will not post a link to here ... I don't want to send them business), they note "The Problem" and then go on to list a half dozen or more links with sensationalistic headlines from different publications. How many marks do you think just read the headlines, and how many do you think actually take the time to click on each link, read the article, and realize that the headline really overstated the matter (as headlines typically do). Then, they note "The Solution" (to a problem that probably doesn't exist), and all you have to do is send them close to $800 for a "home harmonizer" or $280 for a pendant you can wear around your neck to protect you from "electropollution." Sure, as long as you are making up a cure, you might as well make up a name for the supposed disease.
The only defense for the great cons is critical thinking. The key word in that phrase is "thinking." People do not think particularly well when what is driving them is something for which they have a strong bias. In order to think critically, you have to be able to step away from your bias (even if your bias is a completely altruistic need to help that poor Nigerian widow reclaim some small portion of the millions of dollars her husband (the former general)stashed in some bank before he died). I would normally attribute that thinking to greed, but I'm willing to give you the benefit of the doubt.
That said, if it makes you feel really good to wear a talisman against evil spirits, or carry a silver bullet with you in case you meet a werewolf, then, by all means go for it. But, please, shop around first, and try wearing a tinfoil hat. It couldn't hurt and it's a whole lot cheaper.