** 1.hiatal hernia causes food and ACID to reflux back from stomach into esophagus, as a result patient is afraid to consume food, resulting in weight loss. 2. as you are deficient in vitamin B12 and taking medicine for bowel motility, thus mal absorption can be one cause of weight loss. [1 year] PS. do check with blood picture in terms with vitamin B12 deficiency, as it do affect it [reduced white blood cells and platelets], along with neurological examination as it deficiency causes peripheral neuropathy, psychosis. 3. since hiatal hernia and barret s esophagus is there, thus your attending Doctor is giving due consideration in taking up your case, you can incorporate following lifestyle management: . avoid bending/stooping forward or lying immediately after meals. . avoid alcohol,smoking,caffeine,tea . avoid irritant drugs like pain killers. . avoid citrus fruit, tomato, chocolates, spices,fatty food, deep fried food, grapes. . take rice with plain dal or milk or ghee. . do not keep the stomach empty, also do not take heavy meal. 4. As routine examination: . for loss of weight/Immunity: hemoglobin, WBC, ESR, blood sugar, X-ray chest, HIV test [as routine], ultrasonography of abdomen [for any malignancy], any autoimmune disease with relevant examination and investigations. . Good food rich in proteins [cereals,milk,eggs] . Regular gradually increased exercise . Tonics and injections alone are not going to help to build the body mass. Good food and exercise must accompany the medicines for a substantial gain in weight. . As low Immunity is an Issue, thus Rasayana drugs (Immunomodulators) should be instituted in your management; like Ashwagandha, Mandukparni, Shatavri,Trikatu, Vacha, Guduchi i. Vitamin A: helps to maintain Thymus gland which is a powerful antiviral gland : thus mango,carrots,cantaloupe,egg yolk,apricots,pumpkin,papaya, are ideal ii.Vitamin C: is needed for proper functioning of immune system: amla is best