When combined with a diet low in saturated fats, eating walnuts may help lower blood pressure in people at risk for cardiovascular disease, according to a new Penn State study.
In a randomized, controlled trial, researchers examined the effects of replacing some of the saturated fats in participants’ diets with walnuts. They found that when participants ate whole walnuts daily in combination with lower overall amounts of saturated fat, they had lower central blood pressure.
According to the researchers, central pressure is the pressure that is exerted on organs like the heart. This measure, like blood pressure measured in the arm the traditional way, provides information about a person’s risk of developing cardiovascular disease (CVD).
Penny Kris-Etherton, Distinguished Professor of Nutrition at Penn State, said the study suggests that because walnuts lowered central pressure, their risk of CVD may have also decreased.
“When participants ate whole walnuts, they saw greater benefits than when they consumed a diet with a similar fatty acid profile as walnuts without eating the nut itself,” Kris-Etherton said. “So it seems like there’s a little something extra in walnuts that are beneficial — maybe their bioactive compounds, maybe the fiber, maybe something else — that you don’t get in the fatty acids alone.”
Alyssa Tindall, recent student in Dr. Kris-Etherton’s lab and a new Ph.D. graduate in nutrition, said the study was one of the first to try to uncover which parts of the walnuts help support heart health.
“Walnuts contain alpha-linolenic acid — ALA — a plant-based omega-3 that may positively affect blood pressure,” Tindall said. “We wanted to see if ALA was the major contributor to these heart-healthy benefits, or if it was other bioactive component of walnuts, like polyphenols. We designed the study to test if these components had additive benefits.”
For the study, the researchers recruited 45 participants with overweight or obesity who were between the ages of 30 and 65. Before the study began, participants were placed on a “run-in” diet for two weeks.
“Putting everyone on the same diet for two weeks prior to the start of the study helped put everyone on the same starting plane,” Tindall said. “The run-in diet included 12 percent of their calories from saturated fat, which mimics an average American diet. This way, when the participants started on the study diets, we knew for sure that the walnuts or other oils replaced saturated fats.”
- Vitamin K2 – Promotes healthy blood flow and blood pressure and is a powerhouse when it comes to reducing calcium deposits in your arteries and reducing stiffness.
- Pterostilbene –Helps block the creation of Angiotensin II – an enzyme that stiffens the walls of your blood vessels and triggers a hormone that increases the amounts of sodium and water retained by your body.
- Green tea extract – Rich in catechins that have been proven to reduce oxidative stress and soothe inflammation, supporting your heart health.
- Grape Seed Extract – Activates nitric oxide in the lining of your vessels to keep blood platelets from sticking together. It also helps to relax your arteries to promote healthy blood flow.
Other Key Nutritional Supplements That Support Healthy Blood Pressure Include:
- Fish oil (fish or omega-3 polyunsaturated fatty acids): At a daily 3-4 gram dose of oil that contains DHA (docosahexaenoic acid) with EPA (eicosapentaenoic acid) on average, you can reduce blood pressure 8/5 mmHg, lower heart rate 6 beats/minute and lower endothelial inflammation.
- CoEnzymeQ10: Has been shown to lower blood pressure by 17/10 mm Hg at modest doses of 60 mg twice daily in a meta-analyses of 12 studies (n=362). And in another study this dose reduced blood pressure by 26 mm Hg systolic on average of the 55 percent in those who responded to treatment.
- Green coffee extract: Contains chlorogenic acids, shown in a number of studies to significantly lower blood pressure. An average dose of 140 mg daily lowered blood pressure 5.6 mmHg systolic and 3.9 mmHg diastolic.
- Polyphenols: Resveratrol, quercetin, flavonoids, red wine (6 ounces twice weekly), dealcoholyzed red wine, purple grape juice (independent of alcohol content), red grape polyphenolic extract, dark chocolate and other plant-derived polyphenols have been shown to safely reduce endothelial inflammation, increase nitric oxide (a vasodilator) and, thereby, lower both blood pressure and cardiovascular disease. For example, concentrated pomegranate juice (contains polyphenols) 50 ml daily lowered systolic blood pressure 5 percent in a two-week study largely due to its ACE-inhibition (like the prescription ACE-inhibitors such as Lisinopril®) and by 12 percent in a year-long study in which it also significantly reduced atherosclerosis (intima-media thickness reduction by up to 30 percent).
- Soy isoflavones: Contain diadzein and genistein, which are known to lower blood pressure.
- Lycopene extract: Lowered blood pressure by 9/7 mm Hg in a small study (n=30) for eight weeks. When added to ACE-inhibitor, calcium channel blocker or a diuretic medication, it lowered blood pressure by 10/5 mm Hg.
- L-arginine: At 6 grams daily, significantly increases nitric oxide secretion, which is a powerful vasodilator with endothelial anti-inflammatory effects, especially in salt-sensitive persons. A meta-analysis of 11 randomized, double-blind, placebo-controlled trials (n=387) using 4 to 24 grams daily lowered pressure 5.39 mm Hg systolic and 2.66 mm Hg diastolic on average.
- L-carnitine: At 1 gram twice daily lowers blood pressure and lowers insulin resistance. It has maximal effect at 3 grams twice daily for the hypertensive diabetic person.
- Taurine: Has pronounced beneficial heart health effects, including its blood pressure-lowering effect (best at 3 grams twice daily).
- R (alpha) lipoic acid: Lowers blood pressure and improves endothelial dysfunction through beneficial effects on nitric oxide (a vasodilator) and other mechanisms at the optimal dose of 100-200 mg daily.
- Hawthorne berry: Has ACE-inhibition effects (like the prescription ACE inhibitors such as Lisinopril®) and mildly reduces systemic vascular resistance.
- Green tea extract: Contains epigallocatechin gallate (EGCG), which has been shown to be anti-hypertensive.
- Other teas: Dandelion leaf tea is a mild diuretic and, therefore, can lower blood pressure. Fresh ginger tea lowers blood pressure. Hibiscus tea helps lower blood pressure, according to a few studies.
- Ginkgo biloba: Has ACE inhibition effects, improves endothelial dysfunction and has been found to lower blood pressure and slow heart rate, although not all studies agree.
- Garlic and onion extracts: Have been found to lower blood pressure and slow heart rate, although not all studies agree.
- B vitamins: Take vitamin B complex and at least 200 mg of vitamin B1 (thiamin) daily. That’s because niacin (vitamin B3 or nicotinic acid) 500 to 1,000 mg is a vasodilator and, taken as an extended release form, will lower blood pressure and raise good cholesterol levels. Also, pyridoxine (vitamin B-6) stabilizes nitric oxide (a potent vasodilator), as do the other micronutrients vitamin C, vitamin D3 and vitamin E (gamma & delta tocopherols and tocotrienols). Pyridoxine also has calcium channel-blocking effects (like the prescription calcium channel blockers such as Amlodipine® and Nifedipine®).
- Vitamin D3: Make sure your blood levels are at 60 ng/mL or higher, which usually requires supplementation with 2,000 to 5,000 IU daily if your levels are low.
- Magnesium: Low serum magnesium is linked to hypertension. Magnesium intake (diet/supplementation) is associated with lower incidence of hypertension.
- Potassium: A high potassium diet of 5,000 mg daily is recommended (unless you have kidney failure) for optimal heart health and blood pressure.
- High blood pressure medicines — MedlinePlus
- Walnuts may help lower blood pressure for those at risk of heart disease — EurekAlert!