Eating more than three servings of refined grains per day is linked to a greater risk for adverse outcomes in patients with heart failure (HF) compared with diets favoring vegetables and legumes, according to a new study.

The study, published in JACC: Heart Failure, comes as dietary recommendations specifically for people with HF are limited, said corresponding study author Philip Joseph, MD, of the Population Health Research Institute in Ontario, Canada.

While noteworthy studies have focused on sodium and fluid consumption for patients with HF, few have focused on general diet, Joseph said. The study aimed to identify food types affecting outcomes so clinicians can offer practical dietary advice, he added.

The study team analyzed 3798 participants from 25 countries enrolled in the multinational Global Congestive Heart Failure registry. Dietary data was gathered from questionnaire responses.

Links were assessed between consumption levels of plant-based foods and animal-based foods. The plant-based foods included fruits, legumes, vegetables, nuts, refined grains, and whole grains. The animal-based foods included eggs, dairy, fish, poultry, and unprocessed red meat.

Primary outcomes were death or hospitalization from HF. Researchers studied the correlation between an overall healthful diet pattern and these outcomes, measured using a modified Alternative Healthy Eating Index.

Small, Sustainable Changes

In all, 32.5% of participants experienced a primary outcome event, 23.4% died, and 15.6% were hospitalized for HF. Higher legume intake was correlated with a lower risk for the primary outcome, the team found. Moderate vegetable intake, consisting of one to less than three servings per day, was tied to a lower risk for HF hospitalization vs less than one serving a day.

However, a higher refined grain intake of more than three servings per day was linked with a greater risk for hospitalization. Researchers found outcomes associated with some of the other foods — fruits, nuts, red meat, poultry, and dairy — were neutral.

“These findings align with what we already recommend across general cardiovascular care, rather than pointing to a completely separate set of dietary guidelines for heart failure,” said Heather Shenkman, MD, an interventional cardiologist and chair of the Department of Cardiology at Valley Presbyterian Hospital in Van Nuys, California.

“For clinicians, the key is to keep the message simple — eat more vegetables and legumes and fewer refined grains,” she said. “Patients are far more likely to adhere to this recommendation when we focus on small, sustainable changes rather than a complete dietary overhaul. Connecting those changes to outcomes they care about, especially reducing the risk for hospitalization, makes the guidance more meaningful and actionable.”

Intersection of Dietary Factors

Joseph would like to see a replication of these findings in future studies, as well as randomized controlled trial testing of the impact of common dietary patterns on HF outcomes. Other relevant foods and nutrients were not considered, he pointed out, such as sodium, trans fats, sugar-sweetened beverages, or processed meats.

For future studies, the consumption of ultraprocessed foods (UPFs), should be examined, said Dariush Mozaffarian, MD, of the Gerald J. and Dorothy R. Friedman School of Nutrition Science and Policy at Tufts University in Boston, who was the author of an accompanying editorial to the study. Those UPFs include industrial product formulations containing commercial additives and few to no whole ingredients.

“Refined grains are major ingredients of UPFs,” he wrote. “These foods have a high glycemic index and glycemic load and, relevant to HF, are also a major source of salt intake,” he wrote. “Considering the known associations between excess sodium, common in refined grains and UPFs, and adverse HF and other cardiovascular outcomes, the intersections of these dietary factors should be evaluated.”

Joseph and colleagues added that future studies in HF populations are “important to both validate our findings and to identify the underlying mechanisms of these observed effects.”

Joseph reported having no financial disclosures.

Mozaffarian reported receiving research funding from the National Institute of Health to study the impact of nutrition in HF, which supported his writing this editorial comment; Kaiser Permanente Fund at the East Bay Community Foundation; the National Association of Chain Drug Stores Foundation; Google Health; and The Rockefeller Foundation. He reported serving on scientific advisory boards for Brightseed, Calibrate, Instacart Health, January Inc, and WndrHLTH. He reported serving as a scientific consultant to Amazon Health and Google Health and has held equity in HumanCo. He reported receiving chapter royalties from UpToDate.

Shenkman had no financial disclosures.

Martta Kelly is a medical journalist who lives in the metropolitan New York area.