Study: Walnuts Support Lifelong, Heart-Healthy Eating

A new study suggests that a heart-healthy diet can start with eating a handful of walnuts and that the nuts may reinforce healthy habits throughout life.

Research has already shown that walnuts have heart-health benefits, including helping reduce the risk of cardiovascular disease.

However, few studies have looked at whether there are long-term links between eating walnuts or other nuts—or eating no nuts at all—and cardiovascular disease (CVD) risk.

To explore the possible long-term health benefits, researchers from the University of Minnesota School of Public Health looked for links between nut consumption and CVD risk factors to see if walnuts would come out on top.

Cracking the Case on Nuts and Health

For the new study, which was published in Nutrition, Metabolism, and Cardiovascular Disease, the researchers looked at data from about 3,000 young adults aged 18 to 30 years old who were enrolled in the Coronary Artery Risk Development in Young Adults (CARDIA) study.

The participants were mostly Black and White and included a balance of men and women. They came from several locations across the United States—from Birmingham, Alabama to Oakland, California.

The participants’ self-reported diet histories were taken by the researchers three times throughout the study: at the start (baseline), at year seven, and at year 20. Each participant’s physical and clinical measurements were also taken at multiple exams throughout the 30 years.

The participants’ diet histories helped researchers put them into categories based on their nut consumption:

• 352 walnut consumers
• 2,494 other nut consumers
• 177 no nut consumers

The average intake of walnuts during the study was about 3/4 of an ounce a day, and the intake of other nuts among the walnut consumers and the other nut consumers was about 1 and 1/2 ounces a day.

Then, the researchers looked at the participants’ heart disease risk factors, including their dietary intake, smoking status, body composition, blood pressure, plasma lipids (e.g., triglycerides), fasting blood glucose, and insulin concentrations.

Are Walnut Eaters Healthier?

The results showed the potential positive effects of eating nuts (including walnuts) when you’re young. After following up with participants after 30 years, the researchers noted that:

• Walnut consumers had higher self-reported physical activity scores than other nut and no nut consumers. 
• Walnut consumption was linked to lower body mass index (BMI) and waist circumference, as well as lower blood pressure and triglyceride levels. Walnut eaters also gained less weight than other nut eaters.
• Compared to people who did not eat nuts, walnut consumers had much lower fasting blood glucose (sugar) concentrations.
• Walnut eaters had higher total diet quality scores (according to the Healthy Eating Index 2015) than other nut eaters and people who did not eat nuts.

What Makes Walnuts Wonderful?

Lyn Steffen, PhD, MPH, RD, an author of the study and a Professor of Epidemiology and Community Health at the University of Minnesota School of Public Health, told Verywell that the study is one of the longest to suggest that regularly eating walnuts is linked to better health later in life.

“[The findings] reinforce that walnuts might be an easy and accessible food choice to improve a variety of heart disease risk factors when eaten in young to middle adulthood,” Steffen said.

The study also backs up the latest Dietary Guidelines for Americans, which recommend incorporating nuts into your diet.

“A daily one-ounce serving—or roughly a handful—of walnuts provides a wide range of beneficial nutrients,” Steffen said. “Walnuts are the only nut that provides an excellent source of the omega-3 alpha-linolenic acid (ALA).”

Walnuts are also a source of key nutrients that support our heart and overall health, including fiber, manganese, magnesium, copper, iron, calcium, zinc, potassium, vitamin B6, folate, and thiamin.

Easy Ways to Add Walnuts to Your Diet

If the results of the latest study are motivating you to include more walnuts into your diet, there are plenty of easy and creative ways to do so:

• Making a homemade walnut pesto sauce for pasta dishes and sandwiches
• Adding walnuts to smoothie recipes for a boost of plant-based protein
• Sprinkling walnuts on a salad or yogurt parfait
• Dipping walnuts in chocolate for a sweet treat

If walnuts aren’t for you, that’s OK. While they don’t have as many ALA omega-3 fatty acids as walnuts, other nuts like almonds, pecans, and pistachios do provide key nutrients that can support your overall health.