A new study suggests that eating a cup of beans daily reduced cholesterol and inflammatory markers for people with prediabetes

What Can Happen to Your Cholesterol When You Eat Beans Every Day? Here's what to know about the research

Black beans, a good source of fiber, may offer a range of benefits for people with prediabetes.

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  • New research found a link between daily bean eating and reduced cholesterol and inflammatory markers in people with prediabetes.
  • The study has limitations, however, including that it hasn't been peer-reviewed.
  • Experts say adding more of these foods can be a simple and inexpensive way to boost health.

People with prediabetes who ate a cup of chickpeas or black beans daily for 12 weeks lowered their cholesterol, triglycerides, and markers of inflammation, according to research presented Tuesday at NUTRITION 2025, the flagship annual meeting of the American Society for Nutrition.

About 98 million—or one in three—Americans have prediabetes, a condition in which blood sugar levels are higher than normal but not high enough for a diabetes diagnosis.

"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,” said study author Morganne Smith, a doctoral candidate at Illinois Institute of Technology, in a press release. “These findings could be used to inform dietary guidelines, clinicians or public health programs focused on preventing heart disease and diabetes.”

What Exactly Did Study Participants Eat?

With funding from The Pulse Crop Health Initiative (PCHI) of the USDA, researchers from the Illinois Institute of Technology began their study with 72 participants with prediabetes.

These participants were randomly placed into one of three groups: 

  • One that ate 1 cup of black beans per day
  • One that ate 1 cup of chickpeas per day
  • One that ate 1 cup of rice per day

Fasting blood samples were taken at the beginning of the study, at week 6 and week 12.

Beans Were Linked to Lower Inflammation and Cholesterol

By the end of 12 weeks, those who ate chickpeas daily had significantly decreased total cholesterol (related to reductions in both LDL, the "bad" cholesterol, and HDL, or "good" cholesterol) and triglycerides, a type of fat found in the blood. High cholesterol or triglycerides may contribute to plaque buildup in the arteries, raising the risk of heart problems. 

At the 6-week mark, the chickpea group also had lower markers of inflammation, which, over time, can lead to chronic disease. However, these numbers increased again by week 12.

After 12 weeks, the black bean group participants had reduced inflammatory markers, which was more significant than that of the chickpea or rice eaters.

Researchers didn't find that bean consumption was linked with significant differences in glucose levels.

This is promising news for the many Americans with prediabetes or diabetes, said Alyssa Tindall, RDN, PhD, an assistant professor of Health Sciences at Ursinus College, who was not affiliated with the study. “Diabetes creates serious health and economic challenges for millions of people and disproportionately impacts low-income individuals and families,” she told Health. “Beans are a readily accessible and inexpensive food that contains vitamins, minerals, protein and, perhaps most importantly, fiber.”

The Study Has Limitations

While these findings imply positive effects for people with prediabetes, study author Indika Edirisinghe, PhD, a professor of Food Science and Nutrition at the Illinois Institute of Technology, cautioned that the results can’t necessarily be extrapolated for the broader population. “It’s essential to recognize that they cannot be generalized since the study was limited to individuals with prediabetes,” he told Health. “This emphasizes the need for further research into a broader population to fully understand the implications.”

It’s also worth noting that the study is small and has not yet been peer-reviewed. This process is an important step in validating the quality and integrity of scientific research.

How Black Beans and Chickpeas Can Boost Health

According to Sharon Palmer, RDN, MSFS, of The Plant-Powered Dietitian, black beans’ ability to reduce inflammation may come from their high fiber content. This fiber helps nourish the gut microbiome, producing anti-inflammatory compounds.

They also contain plant compounds called phytochemicals, Palmer said, which can produce an "antioxidant and anti-inflammatory action.” 

Although this new study didn’t find a link between black bean consumption and heart health markers, the American Heart Association recommends beans and legumes as part of a healthy eating pattern, noting that they can lower cholesterol. Palmer attributes their cholesterol-lowering potential to fiber’s ability to block cholesterol absorption in the digestive tract.

Chickpeas, too, have been shown to help lower total and LDL cholesterol. Like black beans, they’re a rich source of fiber. In an earlier study, women who added chickpeas to their diets had lower cholesterol levels after five weeks.

Tindall said that foods like chickpeas can support health by replacing other foods. Substituting chickpeas for another protein like beef, for example, decreases saturated fat intake—a diet choice that could help lower cholesterol over time.

Like black beans, chickpeas also contain plant compounds that can produce antioxidant effects. According to Tindall, these may impact the immune system favorably, possibly by modulating the gut microbiome. 

How to Add More Beans to Your Diet

Considering the study’s results, Tindall is optimistic about the effects of black beans and chickpeas on cardiometabolic health for people with prediabetes. “It is promising to see the total cholesterol and LDL-cholesterol reductions after 12 weeks, but it is important to consider the entire diet,” she said.

A heart-healthy diet includes not only beans and legumes but other foods like whole grains, fruits, and vegetables—and doesn’t include high amounts of sugar, sodium, or processed foods.

Still, experts encourage eating black beans and chickpeas regularly for their variety of evidence-based benefits. “Our study showed the benefits of consuming beans in adults with pre-diabetes, but they are a great option for everyone,” said Smith in the release.

A few of Palmer’s favorite ways to eat beans include:

  • Adding canned varieties to salads, grain bowls, wraps, casseroles, soups, stews, and pasta dishes.
  • Throwing them in an Instant Pot (no soaking required) for use throughout the week.
  • Experimenting with them in global cuisine, such as hummus, chickpea pitas, dal, tacos, burritos, and pasta.
Edited by Health with a background in health, science, and investigative reporting. Previously, she wrote full time about parenting issues for the app Parent Lab. Before that, she worked as a reporter for National Geographic covering wildlife crime and exploitation." tabindex="0" data-inline-tooltip="true"> Jani Hall Jani Hall Jani Hall is a news editor for Health with a background in health, science, and investigative reporting. Previously, she wrote full time about parenting issues for the app Parent Lab. Before that, she worked as a reporter for National Geographic covering wildlife crime and exploitation. learn more Read more:

This story originally appeared on: Health News - Author:Sarah Garone