A new study finds that eating a handful of walnuts a day can lower your blood pressure, reduce weight, and in turn reduce your risk of diabetes and heart disease.
Scientists at the University of Minnesota discovered the miraculous potential benefits of nuts after monitoring the diets of 3,300 people for more than 25 years and giving them multiple health checks.
Walnuts are the only nuts that contain the omega-3 alpha-linolenic acid (ALA), which scientists have said may explain this benefit. Fatty acids have previously been linked to better heart health. They say that more studies are needed to confirm the findings, however.
Previous research has linked walnuts to lower blood pressure, and suggested that they prevent diabetes and heart disease. However, these results have not yet been supported by a rigorous clinical trial.
Scientists at the University of Minnesota suggested that walnuts lower blood pressure because they contain omega-3 (stock image).
In the study – published Wednesday in the journal Nutrition, metabolism and heart disease Scientists analyzed the data of 3,341 Americans, who were about 45 years old.
The participants took part in the Coronary Artery Risk Development in Young Adults (CARDIA) study conducted by the University of Alabama between 1985 and 2015.
They were initially interviewed about their diet, and followed for seven, 20 and 25 years of the study.
What is high blood pressure? what are its dangers?
High blood pressure, or hypertension, rarely causes noticeable symptoms. But if left untreated, it increases your risk of serious problems like heart attack and stroke.
The only way to find out if you have high blood pressure is to get your blood pressure checked.
Blood pressure is recorded with two numbers. Systolic pressure (the higher number) is the force at which your heart pumps blood around your body.
Diastolic pressure (the lower number) is the resistance to blood flow in the blood vessels. They are both measured in millimeters of mercury (mmHg).
If your blood pressure is too high, it puts extra pressure on your blood vessels, heart and other organs, such as the brain, kidneys and eyes.
Persistent high blood pressure can increase your risk of several serious and potentially life-threatening conditions, such as:
- heart disease
- heart attack
- stop beating
- peripheral arterial disease
- aortic aneurysm
- kidney disease
- vascular dementia
Of those involved, 340 who ate walnuts consumed an average of about 0.6 ounces (19 grams) a day—the equivalent of seven walnut kernels.
These people were more likely to be female, white and highly educated.
At age 20, he was invited back for a health check-up, where his BMI was measured, along with his activity level and blood pressure.
The results showed that the walnut-eating group had lower blood pressure than those who did not eat nuts.
Blood pressure measurements are shown as two figures, namely systolic pressure – or pressure on artery walls during the heartbeat – and diastolic pressure – or pressure on artery walls – ‘between beats’.
Their blood pressure score was 117.2/73.6 millimeters of mercury (mmHg) among those who did not eat walnuts.
But for those who ate nuts, it was 116/71 mmHg.
The scientists said that people who ate walnuts had significantly lower diastolic blood pressure, or the second figure.
But none of the figures were in the unhealthy category, which Centers for Disease Control and Prevention (CDC) says anything over 120/80 mmHg.
About 20 percent of nut eaters in the study had high blood pressure, while 22 percent did not eat them.
Scientists also suggested that walnuts lead to weight loss and a high-quality diet.
They found that those who didn’t eat nuts had a BMI of 29.7, putting them on the upper end of the overweight range, and 39 percent were obese.
But those who had walnuts had a BMI of less than 29, compared with 35 percent who were obese.
Those who ate nuts had higher activity scores on the paper than those who didn’t.
The scientists also claimed that nut eaters had significantly lower fasting glucose levels, a better risk profile for heart disease, and a higher quality diet.
So-eun Yee, a PhD student in public health at the university involved in the research, said the study claimed walnuts are “part of a healthy diet.”
“Interestingly, nut consumers had a better cardiovascular disease risk factor profile, such as low body mass index, than other nut consumers,” he said.
Scientists said walnuts may help the heart because they are the only nut containing omega-3s, which have been linked to heart benefits.
They also contain many other nutrients, including protein, fiber and magnesium, which may also support heart health.
But the researchers said their results were observational, and clinical trials should be conducted to confirm the results.
It was unclear whether other nuts were having an effect because nut eaters generally ate more nuts than those who did not consume them.