Brief Answer:
Improper management of your problem is culprit.

Detailed Answer:

Hello,
Thanks choosing HealthcareMagic for your query.
Have gone through your details and i appreciate your concerns.
Initially i would like to say that your doctor is not treating you properly.
Why?
Please go through every line and try to understand that basic cause of your problem is reflux of acid from stomach to esophagus and not allergy to foods.Stomach is lined by a natural layer of mucosa membrane which is resistant to acid however mucosa in esophagus is easily destroyed by acid which regurgitates back from stomach.This cause severe irritation of esophagus leading to inflammation. the esophagus reacts to the repeated injury from the acidic fluid by changing the type of cells lining it from squamous (normal cells) to columnar (intestinal-type cells). This transformation, called metaplasia, is believed to be a protective response because the specialized columnar epithelium (epithelium means lining) in Barrett's esophagus is more resistant to injury from acid than the squamous epithelium.However in long term it increases risk of adenovarcinoma by 5%.


So after reading this you can see that food allergy as such has no big role in this problem all we need to do is to control acid production and its reflux back into esophagus.
Have a more detailed look,
The esophagus is a muscular tube that is located in the chest and serves to transfer food from the mouth to the stomach. The lower esophageal sphincter (LES) is a valve that is located at the junction of the stomach with the esophagus. Its function is to prevent acid and other contents of the stomach from coming back into the esophagus. GERD is a condition in which excessive acid-containing fluid refluxes (flows) back into the esophagus, in part because the lower esophageal sphincter is weak.
In some patients with GERD, the esophagus reacts to the repeated injury from the acidic fluid by changing the type of cells lining it from squamous (normal cells) to columnar (intestinal-type cells). This transformation, called metaplasia, is believed to be a protective response because the specialized columnar epithelium (epithelium means lining) in Barrett's esophagus is more resistant to injury from acid than the squamous epithelium.

There is a small but definite increased risk of cancer of the esophagus (adenocarcinoma) in patients with Barrett's esophagus.
If low grade dysplasia is present, endoscopic biopsy surveillance should be done every six months indefinitely.

Now managemebt consists of two step-
1)Control acid production-Just taking prisolec in optimal doses wont help.There are much better PPI's available in market.

2)Prevent reflux of acid formed back to esophagus-This part is completely overlooked by your Gastro.

Please request your gastroenterologist to start you on PPI-antacids like Rabeprazole or Esomeprazole.Prisolec is a badic PPI and better options are there for treating specific conditions like Barett.
Esomeprazole can be used in the dosage as high as 80 mg twice daily.Trials have shown that esomeprazole is superior to other PPI's in controlling reflux symptoms. Also, request him/her to add Domperidone 30mg or Levosulpiride(both are prokinetic)slow release once daily. This will slow down the reflux of acid back.Prokineic should be added in your regimen.

An antacid containing local anesthetic (Mucaine gel ) should be taken 2tsf thrice daily.

Acotiamide is another wonderful new drug and is very effective in controlling symptoms of GERD and esophagitis. In trials- Acotiamide, a gastrointestinal motility modulator, at a standard dose of 100mg thrice daily has significantly affected esophageal motor functions or gastroesophageal reflux in healthy adults.

All these drugs should be given by your gastroenterologist to provide you with relief in your problem.
To prevent the esophageal damage from developing into late stage Barett ask your gastroenterologist to follow aggressive treatment pattern initially. As your symptoms will improve drugs can be tappered off gradually.
Avoid-
Dairy products, which contain sugar lactose that causes gas.
Vegetables, including onions, radishes, cabbage, celery, carrots, brussel sprouts, broccoli, cauliflower and legumes.
Fruit sugar, which is especially high in prunes, raisins, bananas, apples, apricots and fruit juices from prunes, grapes and apples
Fiber.
Fatty foods and carbonated drinks.

Try Eating more fermented foods. These are rich in both good bacteria and enzymes you can try raw natto kefir or cultured veggies. This is probably one of the most important first steps.
Take a high-quality probiotic.
Take external enzyme supplements.
Exercising, to help keep food moving through your system.
Using spices that may help to prevent flatulence. These include turmeric, coriander, peppermint, fennel, sage, chamomile and ginger.
With above mentioned medication and restrictions you cn take meat and corn.

I don't think you are managed properly by your gastro.
Kindly mail this answer to your gastro and ask him/her for an explaination.

Hope i answered your query in details and hope you understood my explaination.
In case you have more doubts feel free to ask.

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