In our early years of medical school, one of the very first things we learnt about was high blood pressure.
Nearly half of adults in the United States have hypertension with only 1 in 4 adults having the condition under control. Despite this, high blood pressure is commonly overlooked because it usually doesn’t cause any symptoms. The condition is dubbed ‘the silent killer’ because of its serious and sometimes fatal complications such as heart attacks, strokes, aneurysms, heart failure, kidney damage and dementia.
High blood pressure is usually treated with anti-hypertensive medications. Although they are sometimes necessary for the patient, medications come with their own set of issues such as side effects, cost and interactions with other drugs. Also, patients find it hard to justify taking a pill for a disease that they cannot physically see.
This is why we also encourage taking up a whole-foods plant-based lifestyle that can help lower your blood pressure naturally.
Read more to find out how!
Nitric oxide is an important biological messenger within the body. One of its key functions is to open up the arteries and allow more blood flow to the area.
A good way to think about arteries is to envision them as pipes. Our arteries are lined by cells known as endothelium (pipe lining). The endothelium releases nitric oxide which tells the muscle fibres within the arterial walls (pipe walls) to relax. The arteries are now dilated (larger pipe) and more blood can flow through.
This process can be seen with nitroglycerin, a drug that is sprayed under the tongue or taken as a pill when someone has chest pain. The drug is converted to nitric oxide which opens up the coronary arteries allowing more blood flow to the heart muscle and the pain is relieved. Similarly, Viagra enhances the signals within the nitric oxide process to open up penile arteries, increase blood flow to the penis and improve erectile dysfunction.
High Blood Pressure and NO
When the endothelial lining of our arteries are damaged, it can impact on the production of nitric oxide. This is called endothelial dysfunction.
Endothelial dysfunction occurs in the presence of free radicals. Factors such as obesity, smoking, sleep deprivation, infections, exposure to pollution can increase the level of free radicals in the body. Conditions such as heart disease, diabetes, kidney failure and viral infections are associated with varying levels of endothelial dysfunction.
Free radicals can disrupt the enzyme that produces NO. When insufficient nitric oxide is produced, arteries are unable to dilate and stiffen. Blood cannot flow through them adequately and blood pressure is increased (think of a kink in a watering hose). Over time, this can result in widespread disease (as the ones described earlier) as the endothelium maintains around 100,000 km of blood vessels in the human body!
Anti-oxidants are molecules that fight free radicals in the body. It prevents the free radicals from damaging the body.
In this case, eating a diet high in anti-oxidants has been shown to prevent free radicals from damaging the arterial lining and allowing the enzyme to produce NO.
Two groups were placed either a high or low anti-oxidant diet for 14 days. The portions of fruit, vegetables, alcohol, fibre and macronutrients were fixed. The only difference between the two diets was the total anti-oxidant capacity. After the study, an ultrasound was used to assess how wide the arteries dilated in each participant. The results showed that a high anti-oxidant diet improved the arteries’ ability to relax and dilate.
The study considered walnuts, dark chocolate, red berry ice-cream and red wine to be higher in anti-oxidants compared to white chocolate, white wine and vanilla ice-cream.
Another way to improve the flow of blood through the arteries is to eat a diet rich in nitrates. Studies have shown that dietary nitrates can be converted into nitric oxide in the body.
Amazingly enough, the foods richest in nitrates are plant foods. The highest source is from rocket leaves (arugula) with 480mg of nitrates per 100g! However, a common intervention used in research is beetroot juice. One study showed a drop in blood pressure of up to 10 mmHg within a few hours of drinking beetroot juice.
We’ll be posting a more in-depth article about beetroot juice soon!
Full of Anti-Oxidants and Nitric Oxide
Eating a whole-foods, plant-based diet is a natural way to bring lots of anti-oxidants and nitric oxide into the body.
There are lots of high anti-oxidant foods out there such as apples, capers, berries (especially blueberries), red grapes, citrus fruits, pecans, goji berries, artichokes, red cabbage and beans. We can never say no to snacking on blueberries and sprinkling goji berries onto our oatmeals. Pecans are wonderful to use in apple crisps while there are countless vegan recipes that use beans. Dark chocolate and red wine are also high in antioxidants and we definitely can never say no to them!
Foods rich in nitrates would include rocket leaves, beetroot, celery, spinach and lettuce. These are perfect in salads (check out our tofu and lettuce wraps!) while drinking beetroot juice is a nice way to switch things up. We also like to add in celery and spinach to our blended smoothies!
- Endothelial dysfunction and insufficient nitric oxide production can contribute to high blood pressure
- Eating a diet high in anti-oxidants can prevent free radicals from damaging the arteries and the enzyme that produces nitric oxide.
- Eating a diet rich in nitrates can also help increase the levels of nitric oxide in the body.
- Foods high in anti-oxidants: blueberries, pecans, goji berries, artichokes, red cabbage, beans, red wine, dark chocolate.
- Foods high in nitrates: rocket leaves, beetroot, celery, spinach and lettuce.
Read more about blood pressure:
Keep in Mind
At Embody Nourish, we believe that a whole-foods plant-based and holistic lifestyle is the best way to nourish the body and mind. We also focus on exercise, mindfulness and the practice of kindness to have a balanced lifestyle. All of these combined can help us achieve our health and wellness goals. Keep in mind that adding or excluding specific foods may help us achieve our goals sooner but they should not be the sole focus of our approach.
- Förstermann U. Janus-faced role of endothelial NO synthase in vascular disease: uncoupling of oxygen reduction from NO synthesis and its pharmacological reversal. Biol Chem. 2006;387(12):1521-1533. doi:10.1515/BC.2006.190
- Franzini L, Ardigò D, Valtueña S, et al. Food selection based on high total antioxidant capacity improves endothelial function in a low cardiovascular risk population. Nutr Metab Cardiovasc Dis. 2012;22(1):50–7.
- Hobbs DA, George TW, Lovegrove JA. The effects of dietary nitrate on blood pressure and endothelial function: a review of human intervention studies. Nutr Res Rev. 2013;26(2):210-222. doi:10.1017/S0954422413000188
- Lidder S, Webb AJ. Vascular effects of dietary nitrate (as found in green leafy vegetables and beetroot) via the nitrate-nitrite-nitric oxide pathway. Br J Clin Pharmacol. 2013;75(3):677-696. doi:10.1111/j.1365-2125.2012.04420.x
- Norman G Hord, Yaoping Tang, Nathan S Bryan, Food sources of nitrates and nitrites: the physiologic context for potential health benefits, The American Journal of Clinical Nutrition, Volume 90, Issue 1, July 2009, Pages 1–10, https://doi.org/10.3945/ajcn.2008.27131
- Rajendran P, Rengarajan T, Thangavel J, et al. The vascular endothelium and human diseases. Int J Biol Sci. 2013;9(10):1057-1069. Published 2013 Nov 9. doi:10.7150/ijbs.7502
- Serban MC, Sahebkar A, Zanchetti A, et al. Effects of Quercetin on Blood Pressure: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. J Am Heart Assoc. 2016;5(7):e002713. Published 2016 Jul 12. doi:10.1161/JAHA.115.002713
- Valtueña S, Pellegrini N, Franzini L, et al. Food selection based on total antioxidant capacity can modify antioxidant intake, systemic inflammation, and liver function without altering markers of oxidative stress. Am J Clin Nutr. 2008;87(5):1290-1297. doi:10.1093/ajcn/87.5.1290