Acid reflux is not just caused by lager and curry, but also our genes

Almost half the chance of developing acid reflux, which doctors refer to as GORD, may be down to our genes, and not just what we eat and drink, a twin study in Gut suggests.

Acid reflux (gastro-oesophageal reflux disease) is one of the most common digestive disorders in the developed world. It is thought that up to one in five people suffers from the characteristic heart burn and/or acid regurgitation every week. Regular sufferers are at increased risk of cancer of the gullet (oesophagus), new cases of which have been rising faster than any other cancer over the past three decades.

The findings were based on 2000 pairs of identical and non-identical twins, who completed a questionnaire on the type and frequency of gastrointestinal symptoms and potential risk factors for acid reflux. These included smoking, excess alcohol, being overweight, and certain drugs, including some heart drugs, oral contraceptives, and drugs for anxiety.

Irrespective of whether the twins were identical (monozygotic) or non-identical (dizygotic), the number of cases of GORD was 18%. But identical twin pairs were significantly more likely to each have GORD than non-identical pairs: an identical twin was over 1.5 times as likely as a non-identical twin to have GORD if their co-twin was affected.

On the basis of this study, and having taken account of known risk factors, the authors conclude that 43% of the chance of developing acid reflux is attributable to genes. Other research seems to back up their findings, say the authors, with previous studies recording several family members with GORD or even oesophageal cancer.