1. Most of the hits on Google are sites that promote or sell the product in question. Typical site names are phlebotinum.com, phlebotinum-advisory-group.net, drlaceyunderall.net, yournaturalhealth.com, and so on. Many strive to look like health information sites, but if they have only good things to say, and an easy link to purchase the product, you can bet it's just a commercial site shilling. If you get a high proportion of hits like Webmd, Mayo Clinic, National Institutes of Health, and maybe stuff like CNN or ABC stories, it has a much greater chance of being a real thing.
2. The remedy is promoted as a solution for vague and ubiquitous maladies. Usual suspects are fatigue, insomnia, body aches, headache, mood problems, low sex drive, weight gain, nausea, and constipation. Now these can be real symptoms of real problems. But when you see a product promoted as solving a long laundry list of these issues, it's time to raise an eyebrow. These symptoms are typically experienced by most people at least some of the time, especially in a culture plagued by poor diet, low rates of exercise, too little sleep, social isolation, and chronic stress.
Most of these symptoms are self-limiting, or can be alleviated by lifestyle change. But most people don't relish a prescription of "eat plenty of fruits and vegetables, exercise regularly, and get 8 hours of sleep a night." Lifestyle changes are difficult to initiate, harder to maintain, and are frankly a total drag. But give us a pill, a cream, or someone waving their hands over us once a week, and we perk right up - seems easy!
3. Self-diagnosis is encouraged. Whether it's checking off the laundry list of vague symptoms, or buying a test kit you can do at home, do-it-yourself is the name of the game for quacks. And if you did get tests at the doctor's office, they encourage re-interpretation. Doctor says your thyroid levels are fine? Well check your number against this web site's "more accurate" scale. Doctor says your hormone levels are healthy? Take a saliva test to find out more!
4. Remedy is promoted by an actress of fading fame. E.g., Jenny McCarthy and Suzanne Somers.
5. Proponents laud how natural the remedy is, and decry the toxins in the environment and/or conventional medicines. Arsenic is as natural as it gets - it's an element! Hemlock is a plant (make sure you get organically grown). Meanwhile insulin for diabetics is synthetic. Using "natural" as a synonym for "good" doesn't make sense. (Also look for the keyword "allopathic" to describe conventional medicine.)
6. Relies on testimonials, anecdotal evidence, appeals to authority. Approaches that work don't need this type of weak support, because they have strong scientific evidence - the kind that attempts to sweep away all the human foibles that can prevent us from seeing what's really happening, and determine if an intervention has a real effect.
7. Provides citations as though they refer to peer-reviewed scientific journals, but the cited material is actually a book, presentation, or web site of an individual proponent of the remedy. It doesn't matter how many letters are after your name - just because you say it doesn't make it reliable. Publication in a respected journal indicates your claims have been examined and probed for mistakes and found robust. Publication on a website means you successfully Googled GoDaddy.
8. Users respond to skeptical inquiry and questioning of the evidence by saying, "I KNOW this works - it worked for me." When the people trying to sell you on something have no clue about placebo effect, confirmation bias, coincidence, self-limiting conditions, and general methods for removing human perceptual bias, you can dismiss pretty much everything they say.
9. Praises or demonizes according to fad. Acai berries are magically delicious, but
10. Invokes the Pentaverate. Promoters wave away criticism as the result of wide-reaching conspiracies involving doctors, pharmaceutical companies, the CDC, and other entities.
11. The remedy is said to have no possible side effects or risks. Generally if something can have an effect, it can have a side effect. If it can change your body in some way, that change might turn out badly for you. Even such benign and universally prescribed practices as exercise and high fiber diets have risks and side effects.