Replacing other snacks with pecans may improve cholesterol, diet quality

Switching daily snack foods to pecans improved cholesterol levels and enhanced overall diet quality, according to a new study by researchers in the Penn State Department of Nutritional Sciences.

The researchers randomized adults who live with or are at risk for metabolic syndrome—a set of conditions that increase a person’s risk for several chronic diseases—to either consume pecans instead of their usual snacks or to continue eating their usual diet.

Participants who ate pecans in lieu of their usual snacks demonstrated reductions across cholesterol measurements linked to poorer heart health compared to those that did not snack on pecans. Additionally, diet quality, as measured by adherence to the Dietary Guidelines for Americans, was 17% higher at the conclusion of the study for participants who consumed pecans.

Results of the study were published in The American Journal of Clinical Nutrition.

“Replacing typical snacks with pecans improved key risk factors for heart disease, including blood cholesterol levels and diet quality,” said Kristina Petersen, associate professor of nutritional sciences at Penn State and co-author of the study. “These results add to the large evidence base supporting the cardiovascular benefits of nuts and add additional insights into how adults can incorporate nuts into their diet to improve the overall quality of their diet.”

The study included 138 adults with one or more criteria for metabolic syndrome, including abdominal obesity, high triglycerides, low HDL, high blood pressure and high fasting blood glucose. Participants were 25 to 70 years old and were randomly assigned into two equal groups: the pecan snacking group, who were asked to consume two ounces of pecans per day in place of snacks typically consumed, and the usual diet group, who were asked to continue their regular diet.

Vascular health data and blood work were collected at the start and conclusion of the 12-week study, and self-reported 24-hour recalls were collected nine times during the research. All participants were also instructed to stop eating all other types of nuts and to keep their non-snacking dietary behavior and lifestyle consistent throughout the study.

In the study, pecan snackers experienced reductions in total cholesterol, low-density lipoprotein (LDL) cholesterol, non-high-density lipoprotein (HDL) cholesterol, the ratio of total cholesterol to HDL cholesterol and triglycerides compared to non-pecan snackers. LDL cholesterol can build up in arteries and increase the risk of stroke or heart attack. HDL—sometimes known colloquially as “good cholesterol”—carries cholesterol back to the liver for removal from the body.

So, both lowering LDL and reducing the ratio of total cholesterol to HDL can reduce the risk for cardiovascular disease. Triglycerides are a necessary lipid for energy storage and metabolism, but high levels of triglycerides also increase the risk of cardiovascular disease.

In addition, study participants who ate pecans showed higher overall adherence to the Dietary Guidelines for Americans 2020–2025, with increased intakes of other under-consumed food groups, such as plant proteins and seafood.

According to the team, prior research by others in the field suggests that chemical compounds with anti-inflammatory properties called polyphenols in pecans may support endothelial function, a key factor in maintaining healthy blood vessels. The current study did not find differences in vascular health outcomes between the two groups, but the researchers said people in the United States should consider consuming more foods with polyphenols—like pecans, fruits, vegetables and whole grains—to support heart health and improve overall diet quality.

“The improved diet quality among pecan snackers—including a higher percentage of calories from polyunsaturated fats and increased fiber and polyphenols—likely also contributed to the observed cholesterol improvements, particularly the LDL-lowering effects,” Petersen said.

The researchers said that replacing a person’s usual snacks with pecans each day could improve cholesterol levels and diet quality, especially if they are at risk of metabolic syndrome.