A first part of the inventive instrument comprises an insertion and removal device in the form of an endoscope which may be inserted through the mouth, pharynx, esophagus and stomach into the small intestine. The inside lumen of the endoscope contains two extendable tools. One extendable tool has a balloon on its end, which may be inflated and deflated. The other extendable tool contains optical fibers for photopolymerizing adhesives and sealants. The second part of the inventive instrument comprises a tubular lining for implantation in and lining of the small intestine, to prevent food from being absorbed into the villi. The lining is anchored in position by means of medical-grade adhesives that are contained on or applied to a mesh sleeve on one end of the lining. The adhesive-coated sleeve is then expanded and glued to the intestine. In operation the lining expands outwardly as digesting food chemicals enter the lining. This allows the normal bodily peristalsis to squeeze the food chemicals through the lining. An alternate tool for an endoscope may be used to apply a coating of biodegradable sealant to the walls of the small intestine to restrict food absorption. Implanting the lining into the intestine or coating the intestine with sealant can be accomplished without surgery.