actually, sublingual can be as good as injection from what i've read. my doc thinks so too, at least wrt vit b12..
anyway, have a read on leaky gut and links to ms:
http://www.msrc.co.uk/index.cfm/fuseact ... pageid/737
a telling excerpt:
"Causes of a leaky gut
•Non-steroidal anti-inflammatory drugs (eg. Aspirin, ibuprofen, NSAIDs etc), antibiotics, cytotoxic drugs, H2 receptor agonist drugs, eg Zantec, Tagamet.)
•Toxic pesticide residues/inhaled chemicals/environmental toxins
•Lectin, which can cause inflammation of the gut lining
•Free radical damage
•Alcohol and tobacco
•Low secretory IgA intestinal antibodies
•Sluggish liver - toxic overload from the liver affects the gut and increases permeability
•Lack of Oxygen
•Deficiency in digestive enzymes or hydrochloric acid"
my naturopath suggested castor oil packs, actually, to combat leaky gut, but i sorted out my diet and supplement regimen instead, to heal.
zinc is definitely part of the picture when it comes to intestinal permeability, and when i tested my zinc levels i was deficient. i absorb things like vitamin D3 many times better now that my zinc status is improved. not sure about what other things might be better absorbed, but i do know that my body also handles the urea cycle much better too.
have fun with that abstract LOL
conclusion: "These results provide new information on the critical role played by dietary zinc in the maintenance of membrane barrier integrity and in controlling inflammatory cell infiltration."
msrc on zinc: http://www.msrc.co.uk/index.cfm/fuseact ... pageid/653
this goes back a couple years, discussion on zinc, membranes, permeability, and zinc:
(good link to a graphic showing tight junctions between cells)
at least with the list of causes in hand we can tease out action items to maximize GI absorption of nutrients. i think it's best to do our utmost to maximize GI absorption and then back it up with other methods. recognizing that in some cases injection is about the only option.