If he is overweight, losing weight alone may relieve symptoms.
Avoid alcohol, smoking , caffeinated drinks, chocolate, onions, spicy foods, spearmint and peppermint - all of which increase production of stomach acid and relax the lower esophageal sphincter
Avoid tightfitting clothes, as they put pressure on stomach
Dont try to use pillows, while sleeping,
Limit fatty foods.
Stop smoking
Source- http://www.mayoclinic.com/health/hiatal-hernia/DS00099/DSECTION=8
Hope it helped
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