What is hypertension?

Hypertension (high blood pressure) is where you have sustained high blood pressure readings. 

Blood pressure is the force of the blood pushing against the walls of the arteries, as it flows from the heart to the rest of the body. 

Primary hypertension represents most cases, where there is no single cause of high blood pressure; it is mostly due to diet and lifestyle factors including lack of physical activity, too much salt in the diet, and too much alcohol. 

Some people have secondary hypertension where the hypertension can be linked to a specific cause e.g. medication or a medical condition. 

Symptoms

Hypertension is often referred to as the ‘silent killer’ because most people have no symptoms. However, those with more severe high blood pressure may experience symptoms such as headaches, chest pain, and shortness of breath. 

Sustained high blood pressure is the leading risk factor for death because of its far-reaching detrimental effects. It puts strain on the heart, and can damage blood vessels in the eyes and kidneys. High blood pressure increases your risk of heart attack, heart failure, stroke, and kidney failure, as well as damage to other organ systems ⁵. It also increases the risk of conditions such as vascular dementia. 

Diagnosis 

Your blood pressure reading is taken with a blood pressure monitor (sphygmomanometer). 

When you have a blood pressure reading, you get two measurements:

• The top number is systolic blood pressure - this is the pressure in your arteries when the heart contracts and sends blood around the body  
• The bottom number is diastolic blood pressure - this is the lowest pressure in your arteries, when the heart relaxes and refills with blood, ready to pump again  

The readings correlate to different stages of hypertension:

Treatment 

The American Heart Association (AHA) and the American College of Cardiology (ACC) recommend diet and lifestyle changes as the first treatment for high blood pressure. 

The evidence shows us that diets rich in plant-foods and lower in animal foods should be the main treatment option for hypertension, combined with the other pillars of lifestyle medicine. 

Several mechanisms are behind the pressure-lowering power of a plant-based diet. Firstly, those who eat plant-based diets have lower BMIs and a lower risk of obesity ⁶. This is mostly due to the high fiber and low fat content of the diet, reducing its overall energy density ⁷. Obesity is a known risk factor for high blood pressure.

They are also high in other compounds that regulate blood pressure: 

1. Plant-based diets are high in potassium which lowers blood pressure and reduces the risk of stroke. It relaxes blood vessels, whilst reducing both the reabsorption of sodium into the kidney, and the production of reactive oxygen species ^{8 9}. Most Americans on a typical western diet do not consume enough potassium ¹⁰. 
2. Dietary nitrate is also a friend of low blood pressure. It gets converted to nitrites, and then to nitric oxide which relaxes our blood vessels and maintains low blood pressure. Leafy green vegetables and beetroot are excellent sources. They help to improve endothelial function and arterial stiffness, which both affect blood pressure ¹¹. The nitrites added to processed meats, like bacon, do not have the same healthful effects. Combined, their protein content and high cooking temperatures convert nitrites into nitrosamines, instead of nitric oxide, which can increase cancer risk ^{12 13}. 
3. Plant-based diets are high in whole grains, which have been shown to significantly lower blood pressure. Scientists estimate that 3 portions of whole grains a day reduces blood pressure and subsequent risk of coronary artery disease by more than 15%, and stroke by 25%. You could cut your risk of stroke by a quarter, just by having some oats for breakfast, and buckwheat and barley for tea! ¹⁴. 

Plant-based diets are low in compounds that increase blood pressure:

4. Low in saturated fat. Saturated fat increases blood pressure because it impairs endothelial function, which affects how much the blood vessels can relax. Red and processed meat, and poultry are major sources of saturated fat on a western diet, and all independently increase blood pressure ^{15 16}. In contrast, polyunsaturated fats can lower blood pressure, found in walnuts and flaxseeds ¹⁷. 
5. Low in AGE content. The cooking of meat, poultry, and fish can generate advanced glycation end-products (AGEs) that increase levels of inflammation and oxidative stress, known risk factors for high blood pressure. Plant-based foods including fruits, carbohydrates, and vegetables contain much lower levels of AGEs, and are high in antioxidants which combat oxidative stress ¹⁶. 

6. Reduced sodium. A plant-based diet cuts out processed foods and meats filled with excess salt, which we know is a major risk factor for high blood pressure.
7. Reduced alcohol consumption is encouraged as part of a whole-food plant-based diet. Excess alcohol increases the risk of high blood pressure through several mechanisms, it can directly affect the heart and decrease nitric oxide production ^{5 18}. 

At Mora, we’ve seen people thrive on a plant-based diet and, with physician support, make an easy transition followed by incredible changes on blood pressure readings. 

Choosing an active plant-based lifestyle can take the pressure off for good. 

Useful links

Books

• How Not to Die by Dr Michael Gregor
• Prevent and Reverse Heart Disease By Caldwell B. Esselstyn

Success stories

• I Kicked Hypertension in a Matter of Weeks with a Plant-Based Diet
• From Cheese-Loving Vegetarian with Sky-High Blood Pressure to Whole-Food, Plant-Based and Healthy

Are you living with hypertension and need help? Join us today to make a change. 

References

1. Joshi, S., Ettinger, L. & Liebman, S. E. Plant-Based Diets and Hypertension. Am. J. Lifestyle Med. 14, 397–405 (2020).

2. Segovia-Siapco, G. & Sabaté, J. Health and sustainability outcomes of vegetarian dietary patterns: a revisit of the EPIC-Oxford and the Adventist Health Study-2 cohorts. Eur. J. Clin. Nutr. 72, 60–70 (2019).

3. Dickinson, H. O. et al. Lifestyle interventions to reduce raised blood pressure: a systematic review of randomized controlled trials. J. Hypertens. 24, 215–233 (2006).

4. Fontana, L., Meyer, T. E., Klein, S. & Holloszy, J. O. Long-Term Low-Calorie Low-Protein Vegan Diet and Endurance Exercise are Associated with Low Cardiometabolic Risk. Rejuvenation Res. 10, 225–234 (2007).

5. Appel, L. J. et al. Dietary Approaches to Prevent and Treat Hypertension: A Scientific Statement From the American Heart Association. Hypertension 47, 296–308 (2006).

6. Tonstad, S., Butler, T., Yan, R. & Fraser, G. E. Type of Vegetarian Diet, Body Weight, and Prevalence of Type 2 Diabetes. Diabetes Care 32, 791–796 (2009).

7. Kahleova, H. et al. Effect of a Low-Fat Vegan Diet on Body Weight, Insulin Sensitivity, Postprandial Metabolism, and Intramyocellular and Hepatocellular Lipid Levels in Overweight Adults: A Randomized Clinical Trial. JAMA Netw. Open 3, e2025454 (2020).

8. McDonough, A. A. & Nguyen, M. T. X. How does potassium supplementation lower blood pressure? Am. J. Physiol.-Ren. Physiol. 302, F1224–F1225 (2012).

9. Aburto, N. J. et al. Effect of increased potassium intake on cardiovascular risk factors and disease: systematic review and meta-analyses. BMJ 346, f1378–f1378 (2013).

10. Hoy, M. K. & Goldman, J. D. Potassium Intake of the U.S. Population, What We Eat In America, NHANES 2009–2010. FASEB J. 27, (2013).

11. Kapil, V., Khambata, R. S., Robertson, A., Caulfield, M. J. & Ahluwalia, A. Dietary Nitrate Provides Sustained Blood Pressure Lowering in Hypertensive Patients: A Randomized, Phase 2, Double-Blind, Placebo-Controlled Study. Hypertension 65, 320–327 (2015).

12. Scanlan, R. A. Formation and occurrence of nitrosamines in food. Cancer Res. 43, 2435s–2440s (1983).

13. Brown, J. L. N-Nitrosamines. Occup. Med. Phila. Pa 14, 839–848 (1999).

14. Tighe, P. et al. Effect of increased consumption of whole-grain foods on blood pressure and other cardiovascular risk markers in healthy middle-aged persons: a randomized controlled trial. Am. J. Clin. Nutr. 92, 733–740 (2010).

15. Steffen, L. M. et al. Associations of plant food, dairy product, and meat intakes with 15-y incidence of elevated blood pressure in young black and white adults: the Coronary Artery Risk Development in Young Adults (CARDIA) Study. Am. J. Clin. Nutr. 82, 1169–1177 (2005).

16. Borgi, L. et al. Long-term intake of animal flesh and risk of developing hypertension in three prospective cohort studies. J. Hypertens. 33, 2231–2238 (2015).

17. Wang, L. et al. Dietary Fatty Acids and the Risk of Hypertension in Middle-Aged and Older Women. Hypertension 56, 598–604 (2010).

18. Sesso, H. D., Cook, N. R., Buring, J. E., Manson, J. E. & Gaziano, J. M. Alcohol Consumption and the Risk of Hypertension in Women and Men. Hypertension 51, 1080–1087 (2008).