Two years ago, authors Siobhan O’Connor and Alexandra Spunt were feeling flush and decided it would be fun to indulge together in pricey keratin hair straightening, also known as the Brazilian blowout. On November 30, 2010, they told Today show hosts how keratin hair straightening inspired them to write, “No More Dirty Looks.”

Because keratin is a protein substance O’Connor and Spunt reasoned that keratin treatment would be safe and healthy. But, when the keratin was flat-ironed into their hair, their eyes began to water and their throats began to burn ? a dead giveaway that there was more than keratin in the air. After the treatment, they loved their shiny pin-straight hair so much that they were willing to overlook the “stinky” cocoa smell it gave off.

Then came a period of bliss in which they enjoyed the confidence of exposure to extreme humidity while remaining sleek and shiny. But the honeymoon ended. They both began to notice “The shine had gone matte, our ends were decimated, and we had crowns of flyaways that were most certainly not there before.”

Their research yielded that the magic ingredient in the Brazilian blowout was not keratin but formaldehyde, which is acknowledged as a carcinogen by the National Cancer Institute. They wondered, “How is that even legal?”

O’Connor and Spunt went on a quest, researching common beauty ingredients and discovering sketchy ingredients in just about everything they used. They learned that “Only 11 percent of the 10,500 ingredients determined by the Food and Drug Administration to be used by the cosmetic industry have been tested for safety by a publicly accountable agency.” And they noted that some of these products were making women look worse. O’Connor and Spunt switched to so-called “clean” products and claim they now look and feel better. They point out that most products are created to survive a long shelf-life and found out that manufacturers sell a 2 ounce pot of face cream for $250 simply because they can.

More important, the skin acts as a transdermal absorber, which is how a nicotine patch supplies a steady flow of nicotine. Therefore, what you rub into your skin may be absorbed into the bloodstream. It’s no surprise that the beauty business is almost entirely self-regulated with safety testing performed almost exclusively by the industry itself.

Product safety, of paramount importance in cosmetic surgery procedures, is especially relevant if you are receiving injectables. The American Society for Aesthetic Plastic Surgery advises that you ask your cosmetic plastic surgeon, “Is the product FDA approved? Is it approved for this use?” If your provider is reluctant or does not directly answer the question, do not proceed with treatment. Further, don’t be embarrassed to ask to see the manufacturer’s label for any skincare or injectable product.