Alan Levinovitz is, by day, a professor of philosophy and religion at James Madison University, focusing “primarily on the relationship between religion and literature, with particular attention to classical Chinese thought and comparative ethics,” according to his official bio. Yet he stepped way out of his lane in the best possible way with his 2015 book The Gluten Lie: And Other Myths About What We Eat, which dissects the history of fad diets and the misunderstandings or blatant falsehoods behind claims that foods like flour, sugar, and salt are “toxins” or otherwise harmful.

The gluten lie of the title is the first major food myth Levinovitz tackles, in part because it is so pervasive right now. While some people suffer from a real autoimmune disease triggered by ingesting gluten, known as celiac or celiac sprue, thousands of others have given up gluten for dubious reasons, including the belief in “gluten sensitivity,” a medical condition for the existence of which there is scant evidence. Gluten is not inherently harmful, but it’s blamed for all sorts of current health evils, from obesity to autism to heart disease to cancer to the quack favorite, “leaky gut syndrome,” which isn’t even real. Numerous books excoriating gluten, including Wheat Belly and Grain Brain, have become bestsellers based on questionable or nonexistent science, taking advantage of a gullible public eager for quick fixes and explanations for their health woes. (Here’s the answer no one wants to hear: obesity, autism, heart disease, and perhaps even cancer are at least partially explained by genetics, and there isn’t much you can do to alter that part of your system.)

Levinovitz starts out by giving the history of glutenphobia and the very real celiac disease, explaining along the way how some doctors refused to accept proof that gluten was the cause of celiacs’ illness, generally because it interfered with their profits. He details the criminal behavior of Walter Kempner, whose name is still easily found on Duke’s campus because his “rice diet” was popular even among celebrities, but who operated a de facto cult, convincing women to be his sex slaves and whipping other patients who didn’t adhere to the diet’s strict limits (around 1200 calories/day). He also covers Dr. Sidney Haas, who believed bananas had some magical cure for celiac disease, so that his patients would get better – until they later ate wheat again. Today’s charlatans may not be so violent or obstinate, but they are profiting off the science ignorance of the public by convincing people that one ingredient is making them sick, offering a quick-fix rather than the more difficult treatment of a healthful, balanced, calorie-limited diet and regular exercise. It’s much easier to just blame the bread.

Gluten isn’t the only enemy Levinovitz exonerates; the new food nemesis is sugar, and he describes the war on sucrose and fructose, along with the past wars on fat and salt, none of which was really based in sound science. (The research on sugar is nascent compared to that on the other fields, for political reasons as much as scientific ones, so I’m not quite ready to give sugar a complete acquittal yet – but he’s right that evidence against it is overstated.) The idea that salt is dangerous still persists across a broad swath of the population, especially those my age and older, because it was everywhere in the 1980s and 1990s, from warnings about salt intake to the prevalence of “salternative” products like NoSalt (which contains potassium chloride, safe in low doses but lethal in moderate ones) or Mrs. Dash (salt-free spice blends). The truth is that sodium is necessary for most people – salt is the only rock we eat, and we eat it because we need it – and only dangerous for a narrow subset of the population, like folks with high blood pressure, Meniere’s disease, or other rare disorders around the body’s homeostasis of sodium. It’s unlikely that you’re eating too much salt, and if you cook most of your food rather than eating out or buying it already prepared, it’s unthinkable.

The low-fat craze, which is also still with us albeit at a lower level of intensity, is based on some outdated science and a history of corporate interference and corruption that led to government condemnation of fat in its dietary recommendations. (Don’t eat what the USDA tells you to eat.) Again, your body needs fat; in fact, you may crave it. Fat contains 9 calories per gram, compared to 4 for proteins or carbohydrates. Humans evolved in environments of scarcity, and fat, typically animal fat, was the most calorie-dense food source available. Such cravings may be ‘hardwired’ in our genes – that is, humans carrying genes that rewarded them for eating fats and sugars fared better in natural selection, and thus craving those foods may now be innate.

The word “natural” in there draws special ire from Levinovitz, as most modern diet fads revolve around some misunderstanding of what a “natural” diet means. Some people simply assume anything artificial is bad, as if your body knows whether a molecule you consume was created in a forest or in a lab. The same applies to the fear of GMO foods. Paleo diets are based on a poor understanding of how early man lived and ate, demonizing foods that can be healthful (whole grains) just because Thag the Caveman no eat them. Others claim you should avoid dairy because it’s not “natural” to consume the milks produced by other species. Levinovitz goes after hucksters like the Food Babe and Joseph Mercola, who demonize harmless ingredients with scary names (and, in Mercola’s case, vaccines and real medicines) to convince you to buy their books and supplements.

Science-ignorance is rampant in our society; I find copious examples every week for my links roundup, and it particularly bothers me when it comes to our governments setting policies that put people’s health and lives at risk. The Gluten Lie aims a little lower; if anything, Levinovitz’s main goal seems to be protecting your wallet, and perhaps your taste buds, from falling prey to groupthink and con artists who’ll peddle what you want to hear in exchange for some of your money. If you want to lose weight, reduce your caloric intake. If you have other health problems, talk to your doctor. But don’t deny yourself the glory of Neapolitan pizza or fresh pasta just because someone on your internet told you that gluten was evil.