Titanium dioxide nanoparticle ingestion alters nutrient absorption in an in vitro model of the small intestine- this paper was published recently – GUO et al., 2017 NanoImpact 5 (2017) 70–82 I discovered that when I digest E-171 I develop severe gut irritation and it initiates severe IBS symptoms (IBS attack) which include severe cramps, bloating and trouble in coordinate peristaltic movements. How I discovered it? I suffer from IBS mixed symptoms (mostly C) for more many years, tried to discover what is the trigger- I was negative for lactose/fructose intolerance, negative for serology of celiac disease, no SIBO; no intestinal parasites. FODMAP diet that help me manage the symptoms but was limited in effects. Tried a lot of elimination diets- the only thing that was consistent is that I cannot consume red hot chili peppers I recently used a medication and supplement for my hair and nails that caused me (both)severe tummy ache and triggered symptoms. When I tried a generic medication which has the same active ingredient but different inactive substances - that did not contain E-171 I did not experienced this symptoms. I than started to look at supplements and medications which triggered my IBS in the past – for some I even did re-challenge to be sure that it is indeed the medication/supplement, guess what? All contain E-171 while alternative medication/supplements which have the same active ingredient without E-171 did not trigger IBS. As I said - I was negative for lactose/fructose intolerance, negative for serology of celiac disease, no SIBO; I had skin rash - reaction in the past for hand watch that was made out of metal and I did not remember which kind since it was more than twenty years ago. E-171 - White in color, Titanium dioxide is extracted from the naturally occurring mineral Ilmenite, (named after the Ilmen Mountains in Russia), an iron-black, heavy, metallic oxide mineral, composed of iron and titanium oxide. Thought not to be easily absorbed, although detectable amounts can be found in the blood, brain and glands with the highest concentrations being in the lymph nodes and lungs, it is excreted from the body with urine. Can be found in tablets and capsules, cottage and Mozzarella cheeses, horseradish cream and sauces, lemon curd, toothpaste, and white paint, also in sweets where it is often used to provide a barrier between different colors. Used to increase opacity in some sauces.