(Not) feeling the burn

Findings from the Nurses’ Health Study, one of the longest running studies of women’s health, show that five diet and lifestyle factors, including regular exercise, can make a significant impact on gastroesophageal reflux (GERD) or heartburn symptoms.

GERD is a common condition, affecting about a third of the U.S. population; the main symptom is heartburn and it is often managed with medications. This new study suggests, however, that following diet and lifestyle guidelines may reduce symptoms substantially and could make medication unnecessary for some patients. It was published as a letter in JAMA Internal Medicine.

The five factors include: normal weight, never smoking, moderate-to-vigorous physical activity for at least 30 minutes daily, restricting coffee, tea and sodas to two cups daily, and a prudent diet.

“This study provides evidence that common and debilitating gastrointestinal symptoms could be well controlled in many cases with diet and lifestyle modifications alone,” said Andrew T. Chan, the study’s senior author. “Given that there are long-term health effects of GERD and lingering concerns about the side effects of medications used to treat it, lifestyle should be considered the best option for controlling symptoms.” Chan is a gastroenterologist, chief of the Clinical and Translational Epidemiology Unit at Massachusetts General Hospital (MGH), and professor of medicine at Harvard Medical School (HMS). The lead author of the research letter is Raaj S. Mehta, gastroenterology fellow at MGH and HMS.

The Nurses’ Health Study II is a nationwide study established in 1989 whose participants return a detailed health questionnaire twice a year. It began with 116,671 participants and has had follow-up that exceeds 90 percent. This study included data from almost 43,000 women aged 42 to 62 who were questioned about GERD or heartburn symptoms from 2005 to 2017 — which represents approximately 390,000 person-years.

The researchers created a statistical model that allowed them to calculate the “population-attributable risk” for GERD symptoms associated with each of the five anti-reflux lifestyle factors — in other words, they estimated how likely it was that each lifestyle factor lowered risk of experiencing symptoms. They found that following all these guidelines could reduce GERD symptoms overall by 37 percent. The more of the specific guidelines a woman followed, the lower her risk of symptoms. Among women using common heartburn treatments (proton pump inhibitors and H2 receptor antagonists), adhering to the guidelines also reduced symptoms.

“We were particularly interested in the effectiveness of physical activity,” said Chan. “This is one of the first studies that has demonstrated its effectiveness in controlling GERD.” This effect, he suggests, could be due in part to exercise’s effect on the motility of the digestive tract. “Being physically active may help with the clearance of stomach acid which causes heartburn symptoms,” he said.

In addition the HMS and MGH, the study has included researchers from the Channing Laboratory (of Brigham and Women’s Hospital), Harvard T.H. Chan School of Public Health, along with Brigham and Women’s Hospital, the Dana–Farber Cancer Institute, Boston Children’s Hospital, and Beth Israel Deaconess Medical Center.

This study was supported in part by the National Institutes of Health.