A number of recent news stories have speculated that the "secret" to the flavor of KFC's famous original fried chicken might now be out, after the Chicago Tribune published a recipe by Colonel Sanders' nephew, Joe Ledington. Ledington claimed that the recipe for breaded chicken with 11 herbs and spices is the very recipe that he mixed up as a boy when working for the first KFC restaurant (then called the Harland Sanders Cafe, later renamed Kentucky Fried Chicken).

Lost in the media frenzy over whether or not Ledington's recipe has actually outed what KFC calls "one of the biggest trade secrets in the world," is the fact that the famous 11 herbs and spices are hardly the major factors giving a modern bucket of KFC "original recipe" chicken its flavor. Like many KFC products, "original recipe" chicken is packed with flavoring chemicals, including the brain-frying neurotoxin monosodium glutamate (MSG).

The real secret ingredient

But are these herbs and spices – or any herbs and spices – actually the secret to the flavor of KFC's original chicken? According to the KFC website, the Original Recipe chicken is actually made by first marinating the meat-on-the-bone in a mix of salt, sodium phosphate and MSG. It is then breaded in a mix made from flour, salt, tricalcium phosphate, whey, nonfat milk, egg whites, corn starch, potato starch, maltodextrin, triglycerides, "natural flavoring," gelatin and – last of all – " Colonel's Secret Original Recipe Seasoning."

So the bulk of the flavor in the chicken – as in many of the foods sold at KFC – actually comes from additives such as natural flavoring and MSG.

MSG is a synthetic chemical designed to trigger the glutamate taste receptors on the tongue, which give food a richer, more savory taste. Unlike naturally occurring glutamate, however – which is found in foods such as anchovies, tomato paste, soy sauce, Worcestershire sauce and parmesan cheese – MSG has been linked to a wide range of health problems.

People who are particularly sensitive to MSG can experience symptoms from stomach cramps and nausea, to heart palpitations, dizziness, joint pain or shortness of breath. But studies have shown that MSG likely acts as a neurotoxin in all mammals. It kills neurons, particularly in the hypothalamus.