George Zaidan is a chemist, not a nutritionist. Faced with so many contradictory claims about foods and cosmetics, he brings his scientific experience to explore what is good or bad for us. If you’re looking for answers that confirm your beliefs: “Cheetos are poison” or “Cheetos are harmless” this is not your book. Rather this is a light science book that tries to be funny with lots of young boy humor (he likes to say “shit” a lot) that sets out to help the reader understand how scientific studies are done, problems with certain types of studies, and how useful or not they can be.
The book covers a lot of stuff. Is processed food bad for you? How is processed food defined? It is clear that smoking will shorten lives, does vaping do the same? Is coffee good or bad for you? Sunscreen? What creates the public pool smell?
Processed food is not well defined, and thus difficult to categorize. Zaidan uses the terms: unprocessed, processed and ultra processed food, but even those aren’t hard boundaries. Honey is highly processed, but not by humans. Numbers of ingredients aren’t helpful either, because everything and everyone is made up of chemicals. Coffee is made up of a lot of chemicals. A lot of food processing involves eliminating water in order that the food won’t spoil.
Zaidan does a good job explaining that in order to determine whether a food or substance is safe there mist be a preponderance of observational evidence built up over a period of time. Your study says that cigarettes cause cancer, can you replicate it? (In this instance, yes) Is vaping safer than smoking because e-cigarettes contain fewer harmful ingredients? Not necessarily. Nicotine is a highly toxic substance. Too much (like drinking the liquid in the vape cartridges) can kill a person. Cyanide, found in plants, is a single chemical and is quite deadly.
Much of the book is about how nutritional studies are conducted. Observational studies that rely on self reporting are only as good as the reporters. Scientists are motivated to find associations, and statistics can be misleading. There are many variables in subjects of studies and in foods, thus finding associations of risk, much less causation is very difficult. He doesn’t get into claims that foods are designed to taste good in a way that may cause you to over consume them.
So ultimately what is good or bad? With respect to ultra-processed food, it’s still too early to tell.
So if Cheetos are your jam, an occasional bag won’t kill you. Statistically, if you want to extend your life expectancy the following things can add a few years: Don’t smoke; be physically active 2 – 4 hours a week; eat healthy (primarily not too much). Finally, ignore most news about food and health studies, but do pay attention to notices about contaminated food, water or health products.
You don’t have to read Ingredients to reach the same conclusions, but there are enough fun factoids about science to make it a good book to listen to while you are walking, driving or doing chores.