Daily bean consumption linked to improved heart and metabolic health

A new study suggests that regularly eating a cup of beans a day may offer measurable benefits for heart and metabolic health. Incorporating beans into daily diets could serve as a simple, cost-effective way to reduce the risk of chronic diseases.

The 12-week study of 72 people with prediabetes showed an association between chickpea consumption and improved cholesterol levels, while eating black beans was linked with reduced inflammation.

Individuals with prediabetes often exhibit impaired lipid metabolism and chronic low-grade inflammation, both of which can contribute to the development of conditions like heart disease and type 2 diabetes. Our study found that bean consumption helped significantly lower cholesterol and reduce inflammation in people with prediabetes, although glucose levels were not changed."

Morganne Smith, doctoral candidate at Illinois Institute of Technology

Smith will present the findings at NUTRITION 2025, the flagship annual meeting of the American Society for Nutrition held May 31–June 3 in Orlando. Indika Edirisinghe, PhD, and Britt Burton-Freeman, PhD, from Illinois Institute of Technology, are the principal investigators for the study.

Black beans and chickpeas are commonly consumed but often overlooked in detailed studies regarding their impact on cholesterol and inflammation among those at risk for heart disease or diabetes. The new study is part of a larger project exploring how eating black beans and chickpeas affects inflammation and insulin response through gut microbiome activity.

"Our study showed the benefits of consuming beans in adults with pre-diabetes, but they are a great option for everyone," said Smith. "These findings could be used to inform dietary guidelines, clinicians or public health programs focused on preventing heart disease and diabetes."

To increase the study's relevance to everyday life, the researchers conducted the study with participants in free-living conditions. Participants were randomly assigned to eat either 1 cup of black beans, chickpeas or rice (control) for 12 weeks. Blood samples were taken at baseline, 6 weeks and 12 weeks to track cholesterol, inflammation, and blood sugar, and glucose tolerance tests were conducted at the beginning and end of the study.

For the group consuming chickpeas, total cholesterol significantly decreased from an average of 200.4 milligrams per deciliter at the beginning of the study to 185.8 milligrams per deciliter after 12 weeks. For those eating black beans, the average level of pro-inflammatory cytokine interleukin-6 - a marker of inflammation - was 2.57 picograms per milliliter at baseline and significantly decreased to 1.88 picograms per milliliter after 12 weeks. No significant changes were observed in markers of glucose metabolism.

The researchers say that swapping beans - whether canned, dried or frozen - in place of less healthy options is a great place to start when trying to eat more beans. However, be aware of any additional ingredients like salt or sugar, depending on what you buy.

"There are a lot of ways to incorporate beans into your regular diet as a cost-effective way to support overall health and reduce the risk of chronic diseases," said Smith. "You can blend them to add some thickness to a soup base, add them as a salad topping, or pair them with other grains like rice or quinoa."

For the next phase of this project, the researchers plan to examine how consuming black beans and chickpeas influences gut health to better understand the connection between the gut microbiome and metabolic health. 

Smith will present this research at 8:30 – 8:42 a.m. EDT on Tuesday, June 3, during the Clinical Nutrition Perspectives: The Influence of Diet on Metabolic Health, Inflammation, and Cardiovascular Risk session in the Orange County Convention Center.