 The latest review on diet and the risk of inflammatory bowel disease, such as ulcerative colitis and Crohn's disease, suggests that of all dietary factors, animal protein from meat and fish was found most associated with a higher risk of inflammatory bowel disease. They think it might be the blood components in meat that degrade into carbon monoxide, or some of the carcinogens created by cooking muscle or added to processed meats intentionally. And then, of course, there's the arachidonic acid, the pro-inflammatory omega-6s, and meat contains huge amounts of certain bacteria that have been linked to inflammation. The antibiotics in meat may even be mucking with people's intestinal flora. Who knows? Either way, a diet high in animal protein may be associated with not only increased risk of getting inflammatory bowel disease in the first place, but relapsing back if you already have it, consistent with the data I presented last year that even just a semi-vegetarian diet was highly effective in preventing relapses in Crohn's disease, for example. But one potential risk factor that I had never heard of was micro or nanoparticles. Foodstuffs in developed countries contain increasing quantities of micro particles, such as titanium dioxide, used by the millions of tons as a brightening pigment, mostly to make white-colored paint, but also as a food additive to make white-colored food. So much so that people eating conventional diets may be ingesting a trillion particles of titanium dioxide every day. Who cares, though? Well, a few years ago, researchers found evidence of micro and nanoparticles in all 18 out of 18 samples of diseased colons they looked at, either colon cancer or inflammatory bowel, but none in the three healthy colons they looked at from folks who died in a car accident or from a heart attack. Now look, that's a tiny sample, but it got people thinking, and more importantly, putting it to the test. They took intestinal biopsies from people and added some titanium dioxide to see if it would cause inflammation. Here's the level of secretion of an inflammatory cytokina baseline, and then here's after you add the titanium dioxide they use in food. Nothing. No inflammation. Maybe they got some dead tissue or something, so they tried adding a little or a lot of bacterial endotoxin. All right, that worked. That got an inflammatory response. Before declaring the food additive safe, though, they tried one last thing. What if you combine these together? The titanium dioxide and a little bit of endotoxin mixed together. Presumably you'd still be down here somewhere, but instead got this. So their thinking was that while titanium dioxide itself is inert, non-toxic, in the gut it may act as transporters of inflammatory substances like endotoxins from the inside of our gut into the gut wall, kind of a Trojan horse mechanism. What happens in a Petri dish, though, may not happen in a person. How are you going to test the theory in people, though? You can't go around trying to give people inflammation, so they took people actively suffering from Crohn's, took micro-particles out of their diet, and saw if they got better. 18 patients with active Crohn's, nine stayed on their regular diet, and nine were placed on a low micro-particle diet, and within a month, those on the low micro-particle diet had a significant decrease in disease severity. And by the end, seven out of the nine were in remission, whereas none were in remission in the regular diet group. Now in addition to removing things they expected to contain titanium dioxide, coffee whitener, white cheese, powdered sugar, they also removed processed meats and fish, fearing that they had micro-particles in them, too. But that complicates things, right? Because just cutting down on meat alone is considered one of the most powerful Crohn's interventions, so maybe that's why they got better, maybe avoiding titanium dioxide had nothing to do with it. And indeed, a larger trial in which both groups were told to cut down on processed meat and seafood, they both improved the same. Regardless of their micro-particle intake, which is consistent with this study that did not find that Crohn's patients were eating significantly more white processed foods like crispy shell chewing gums, marshmallows, powdered donuts, etc. So where does that leave us? Well, maybe high concentrations of dietary micro-particles should not be completely ruled out as a potential contributor to intestinal inflammation, but there's just not much evidence suggesting it's harmful. If you look at the most concentrated sources, though, out of nearly 100 products tested, none of them are particularly health-promoting, so if you want another excuse to avoid hostess donuts, well then, there you go.