How can you that all the vitamins are being absorped?

There are water miscible forms of Adek meaning they don't require the regular fat for absorption and some come in sublingual. A little coconut oilenhances there absorption because it is absorbed differently than other fats. There are more bio available forms of some of the b vitamins: b6/p5p, thiamin/bento thiamine, pantethine may be more helpful version of pantothenic acid,and others. Supplements with folate rather than folic acid may be better as folic acid is metabolized in small intestine whereas folate is metabolized in the liver. Swanson vitamins carries most of these reasonable and will talk to you about them over the phone. Many reputable companies carry them. I use to have website listings for all this. Hope you can do your own Google search. They told me when my levels were off to work with a hemotologist. It gets expensive and confusing. There also use to be wonderful websites to that listed nutrients for remylination, which I cannot find now. I know I'm not much help but, just wanted to give you food for thought and maybe you can look some things up.

Have had a lot of trouble absorbing B-12 and was anemic. The doctor put me in self-given B12 shots and sublingual B12 drops. That did it for me since it goes directly into the bloodstream. Also take folic acid, 2 pills a day.

Blood levels of some major vitamins and minerals can be measured. B12, iron, vitamin D, omega-3, and calcium. Magnesium levels can be tricky and a special test is needed. A hematologist can advise you on the nutrients that can be measured.

It might be a good idea to supplement with zinc since that is a common deficiency with IBDers. At the height of my last flare my blood measurements were so bad that I was referred to an oncologist to check for lymphoma.

I had lost so much blood and became very anemic. I insisted on getting all of my blood lipid levels checked. It turned out that my levels of B12, folic acid, CRP, ferritin, and other lipid levels were so badly skewed that just to be safe they sent me to an oncologist for further tests. Started some supplementation and as soon as I went into remission my blood levels returned to normal.