There ain’t no such thing as a free lunch, as the adage goes, and new research suggests that it rings true for physicians.

Doctors who received industry-sponsored meals — which cost an average of less than $20 — were found to prescribe the promoted, brand-name drug at a higher rate than those who did not, according to a new analysis of Open Payments and Medicare Part D data published in JAMA Internal Medicine. The researchers noted that they found an association between meals and the higher rate of prescribing — not a direct cause-and-effect relationship.

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During these meals, drugmakers present information about their medications to attendees. Industry meals comprise 80% of the total number of payments made by drug and devicemakers to physicians.

The study took a look at at almost 280,000 doctors and 63,500 payments. The analysis uncovered that doctors who received industry payments were 18% more likely to prescribe cholesterol-lowering drug Crestor, 70% more likely to prescribe beta-blocker medicine Bystolic, and 52% more likely to dole out hypertension treatment Benicar.

Researchers also found that the more meals doctors received, the more likely they were to prescribe promoted treatments. Physicians who received industry payments in the analysis were most likely to be male, solo practitioners and work in the South.

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John Kamp, executive director of the Coalition for Healthcare Communications, downplayed the findings, noting that, “Information is power. The more information prescribers obtain, the more they are likely to use a drug safety and effectively. Dinner regulations are regulated by the FDA to ensure that the information is consistent…The fact that doctors have dinner as a part of the process does not change the facts of the presentation.”

Holly Campbell, a spokesperson for the industry-lobbying group PhRMA, said in an email that the study lacks clear evidence that meals influence new prescriptions. “This study cherry-picks physician prescribing data for a subset of medicines to advance a false narrative. Physician prescribing patterns are dynamic and based on individual patients’ needs,” she noted.