Eating about a handful of nuts each day may be associated with a lower risk of developing high blood pressure, according to a new systematic review and meta-analysis.
The research, published August 4 in the British Journal of Nutrition, analyzed eight prospective studies and found that each additional 1-ounce (28-gram) serving of nuts consumed per day was associated with a 20% lower risk of developing hypertension.
The findings add to previous research linking nut consumption to a lower risk of cardiovascular disease.
However, previous research specifically examining the relationship between nut consumption and high blood pressure has produced mixed results.
How nut consumption was linked to hypertension risk
The analysis included eight prospective studies involving 143,380 adults ages 18 to 87. During follow-up, 20,665 cases of hypertension were identified.
When researchers compared people who consumed the most nuts with those who consumed the least, higher nut intake was associated with a 16% lower risk of developing hypertension.
Each additional 28 grams of nuts consumed per day was associated with a 20% lower risk.
Researchers also looked at how the risk of hypertension changed at different levels of nut consumption. Compared with eating no nuts, consuming about 30 grams per day was associated with a 26% lower risk.
Researchers did not find evidence of further reductions in risk at higher intake levels.
“Because this was based on observational studies, we cannot say that eating nuts directly caused the lower risk,” Michelle Routhenstein, Preventive Cardiology Dietitian at Entirely Nourished, who wasn’t involved in the study, told Healthline.
“That does not mean nuts prevent or treat high blood pressure on their own. Rather, they can be a really helpful part of an overall heart-healthy eating pattern,” she said.
How can nuts affect blood pressure?
Nuts contain a variety of nutrients that may support cardiovascular health, including:
- fiber
- unsaturated fats
- magnesium and potassium
- vitamins E, K, C, and several B vitamins
- plant-based protein
Research suggests that these nutrients may help support healthy blood pressure.
Magnesium, for example, can act as a natural calcium channel blocker, helping blood vessels relax and widen through a process known as vasodilation. This may help lower blood pressure.
Potassium may also help manage blood pressure by reducing the effects of sodium and easing tension in blood vessel walls.
Kristin Kirkpatrick, President of KAK, Consulting, LLC, and a dietitian at the Cleveland Clinic Department of Wellness & Preventive Medicine in Cleveland, Ohio, who wasn’t involved in the study, told Healthline that all nuts can benefit cardiometabolic health.
“However, nuts such as walnuts, peanuts, and almonds have been shown to have higher amounts of L-arginine, which acts as a vasodilator to help open blood vessels and could have a positive impact on blood pressure,” she said.
Routhenstein added that, based on this study, there is no single “best” nut to eat for better health.
However, she also noted that pistachios are worth highlighting because research suggests they may modestly lower systolic blood pressure, potentially due to their potassium, unsaturated fats, fiber, and antioxidant compounds.
