Frequent heartburn or acid reflux are symptoms of a condition called GERD, or gastroesophageal reflux disease, which occurs when a sphincter muscle in the lower esophagus stops working properly.

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Dr. Clarke says he found that about one-third of his patients with heartburn didn't get better on proton-pump inhibitors, or have evidence of acid reflux, but in virtually every case, they had severe stress in their lives.

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Daniel's refusal to eat or drink came after he suffered from acid reflux as a baby and now has a fear of consuming food.

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The goal is to tighten up or otherwise improve the faulty valve, called the esophageal sphincter, that lets acid reflux back into the esophagus.

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But the procedure didn't significantly decrease acid levels or medication use, prompting some doctors to theorize that Stretta is destroying nerve endings without fixing reflux at all.

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