After looking at Google images, the spleen is on the upper left abdomen, too!  An organ, part of the lymphatic system for immune function.  A filter.  Wonder how this relates to gluten sensitivity?

Hey, mistake in my post,  pancreas TAIL is on the left side.  Head is middle back of belly,

Hello, everyone, This upper left side pain is interesting to me.  I have this same pain almost all the time.  Started 2009 when I got diverticulitis for the first time.  Then had left ovarian cyst removed and a diagnosis of endometriosis all over inside.  Been attempting gluten-free since 2018.  It's not perfect, but still have that left sided pain.  Like up under the rib cage.  I believe the pancreas head is on that side, so I often wonder if I have a tumor or something there.  But it could also be an endometriosis adhesion in my belly.  I never got scraped.

One of my biggest issues is when a brand chooses to label one item gluten free, but not another. Why is Hunt's diced tomatoes labeled gluten free, but not the paste or sauce? I would have assumed they were all gluten-free, but why label one and not the others? It makes me suspicious.   

Most of these items would be naturally gluten-free, with very little chance of cross contamination, thus they don't typically label them as gluten-free. If wheat is a potential allergen large companies disclose this in the ingredients as "Allergens: wheat."