A new study published in Nature offers an explanation for the rise in incidence among Americans of irritable bowel diseases (IBD), including colitis and Crohn’s disease. It points to the concentrated milk fat used in processed and confectionery foods, which might appear on ingredients labels as evaporated, condensed, dried or powdered milk.
As explained in a university press release, “Certain saturated fats that are common in the modern Western diet can initiate a chain of events leading to complex immune disorders such as inflammatory bowel diseases in people with a genetic predisposition.” The chain of events begins with the ingestion of milk fats. These fats “are particularly difficult to digest and require the liver to secrete a form of bile that is rich in sulfur,” which enables the microbe Bilophila wadsworthia to proliferate. The elevated presence of B. wadsworthia can induce inflammation in those who are predisposed to bowel diseases.
“This is the first plausible mechanism showing step by step how Western-style diets contribute to the rapid and ongoing increase in the incidence of inflammatory bowel disease,” study author Dr. Eugene Chang, a professor of medicine at the University of Chicago, said. “We know how certain genetic differences can increase the risk for these diseases, but moving from elevated risk to the development of disease seems to require a second event that may be encountered because of our changing lifestyle,” he said.
Concentrated milk fat is “a certain saturated fat.” It is a processed one, to be exact, and its production involves separating and concentrating the fat from cream and placing it in a vacuum to remove almost all of the moisture using equipment like a “specialized phase inversion unit.” It is a product that stays stable at high temperatures, stores for a long time and, as one manufacturer of the product explains, “provides a consistency of composition that pure butter or cream cannot provide due to natural variation.”
In short, the milk fat fed to the mice by the University of Chicago researchers was not simply, say, a dab of butter or a dollop of cream, but rather a processed rendition of saturated fat that was created for the singular purpose of expediting the manufacture of a very wide variety of processed foods. Many natural properties and any “natural variation” of the kind one would find in real butter, fresh cream or, for that matter, any real and fresh food are a mere nuisance for food manufacturers.
One can easily see how news of this study might re-energize public opinion against saturated fat and whole-fat dairy products, but that’s not, in my opinion, the lesson to be learned here. For one thing, people have been enjoying milk and other dairy products for centuries without any known incidence of IBD at the rate it’s being diagnosed today. The difference here is that the milk fat is industrially processed. The problem is that our diets now include a vast and voluminous array of processed foods, foods to which our bodies are not yet entirely adapted.
Are processed milk fats causing IBD in some people? The evidence isn’t conclusive, and, besides, the study involved mice, not humans. Matching up individual industrial ingredients with individual ailments seems to me an impossible exercise. It makes more sense to lay off processed foods as a general rule and for best health.
Photo Credit: Steve A Johnson