Hypertension is reaching epidemic proportions across the globe. Nearly half of all adults in the US alone have high blood pressure.
Having elevated blood pressure is one of the primary risk factors for cardiovascular diseases which include heart disease and stroke – two of the leading causes of death worldwide, according to the World Health Organisation.
But hypertension is known as the ‘silent killer’ for a reason. The majority of people aren’t aware they even have it, and only one in four people diagnosed with it have the condition under control.
So what can be done to combat hypertension – a condition which can cut an average of 5 years off the life expectancy of men and women?
We look at the science and share 5 key ways that losing weight and optimising our diet and lifestyle can drastically reduce the risks of high blood pressure.
1. Weight Loss Improves Insulin Sensitivity
One of the most consistently agreed-upon methods of reducing blood pressure is weight loss, especially if you’re obese. One mechanism behind the benefit of weight loss in overweight people is its effects on improving insulin sensitivity. Insulin is often seen as the ‘bad guy’ of body composition, but this is far from the case; it is essential for repairing and growing tissue. Think of insulin as a general storage hormone.
Insulin influences fat metabolism, fat storage and inhibiting the mobilisation and burning of fat. It is essential for transporting glycogen for storage in skeletal muscle and the liver, making it key for muscle growth.
However, being overweight or obese results in ‘insulin resistance’, which is when the body cannot effectively store and uptake glycogen from muscle stores. This results in the overproduction of insulin and chronically high blood sugar levels.
However, the effects of insulin resistance extend far beyond these metabolic effects; it can also increase your blood pressure. Insulin can raise your heart rate, increase fluid retention, and influence how your blood vessels contract and expand.
These impact blood pressure by:
- Raising your heart rate. Insulin increases blood pressure by pumping more blood into your vessels, squeezing more into a space that remains the same size.
- Fluid retention. Insulin increases the volume of blood plasma flowing through your vessels at any one time and increases the pressure on your veins and arteries.
- Blood vessel contraction and expansion. Insulin decreases and increases the width of your veins and arteries to impact how freely blood flows.
Experts theorise that insulin resistance causes blood pressure to rise due to ‘selective insulin resistance’, where insulin doesn’t work in some instances (like managing blood sugar) but continues to work in others (influencing blood pressure). As insulin resistance causes chronically elevated blood sugar levels, so too can blood pressure become chronically elevated.
2. Weight Loss Improves Arterial Structure and Function
Another mechanism linking weight loss and blood pressure is how body fat impacts your blood vessels’ structure and function. Obesity, insulin resistance and type 2 diabetes are well associated with a ‘stiffening’ of blood vessels and arteries, which results in their lining becoming dysfunctional. As a result, they cannot effectively expand and contract as your heart rate increases, causing an increase in blood pressure. This phenomenon is known as endothelial dysfunction.
Studies show that you become far more likely to develop arterial stiffness and endothelial dysfunction if you’re overweight. Other side effects of endothelial dysfunction include an increased likelihood of atherosclerosis (plaque build-up) and reduced production of nitric oxide, a compound that causes your blood vessels to expand. Plaque build-up results in a narrowing of your veins and arteries, causing blood pressure to rise.
While the mechanisms behind the direct effect of fat loss on blood pressure remain unclear, improving your body composition has indisputable benefits for improving blood pressure.
3. Exercise Improves Blood Pressure Through Multiple Mechanisms
It is clear from the research that exercise is a crucial lifestyle component that impacts healthy blood pressure. Regular medium-intensity to high-intensity exercise, such as resistance training, can lower blood pressure by 11/5mmHg systolic and diastolic.
Exercise reduces blood pressure by:
- Reversing insulin resistance
- Improving weight loss
- Improving how your circulatory system works
- Increasing microvessel growth
Exercise reverses the effects of insulin resistance on your heart rate, fluid retention, and blood pressure. Exercise causes what is known as ‘non-insulin-dependent glucose uptake’, which means that your body can store and use glucose without insulin. As a result, your blood pressure reduces as your circulating insulin levels lower.
Alongside weight loss, exercise can improve endothelial function and increase nitric oxide production, therefore lowering blood pressure. Overall, your blood vessels become more pliable and can manage blood flow more effectively.
Evidence shows that regular exercise can increase angiogenesis (the growth of new blood vessels), a process that tends to decrease with hypertension. Exercise enhances the production of a chemical called vascular endothelial growth factor, a crucial component in angiogenesis. As the body forms more microvessels, the circulatory system can handle more blood, thereby helping to reduce blood pressure, .
4. Dietary Choices Play a Key Role in Reducing Hypertension
Diet is one of the most well-researched, discussed, and influential factors impacting blood pressure. Even though energy balance is always the main priority for weight loss, evidence consistently supports that food choices and dietary patterns significantly influence your risk of hypertension.
A key component that can positively or negatively influence blood pressure is electrolytes, namely sodium and potassium. Electrolytes are minerals in blood, sweat and urine that carry an electrical charge and support many physiological processes within the body. The amount of sodium and potassium you eat can influence your blood pressure by up to 10 mmHg.
Sodium has a notable role in altering blood pressure by increasing fluid retention. In simple terms, where sodium goes, fluid follows. In the same way that fluid retention affects blood pressure during insulin resistance and obesity, decreasing your salt intake can also support healthy blood pressure.
Potassium has a lesser-known influence on blood pressure and can increase ‘natriuresis’, the process through which the body eliminates excess sodium to restore healthy fluid balance. Potassium also improves endothelial function and reduces arterial stiffness, allowing your blood vessels to handle increased blood flow.
Another food compound that plays a major role in blood pressure management is a type of antioxidant known as polyphenols. Evidence shows that a high intake of flavonoids, a type of polyphenol, may decrease the risk of hypertension by up to 10%. Polyphenols appear to be so beneficial because of their role in reducing oxidative stress. Oxidative stress can affect blood vessels in the same way as endothelial dysfunction, reducing their ability to expand and contract and increasing plaque build-up. It has even been theorised that oxidative stress may lead to endothelial dysfunction.
High oxidative stress represents an imbalance between the free radicals that your body produces through natural metabolism and the antioxidants that clear them. While free radicals are a normal part of human physiology, antioxidants like polyphenols are a vital counterbalance that supports health.
Examples of foods high in polyphenols include:
- Berries: blueberries, blackcurrants, blackberries, raspberries, strawberries
- Herbs and spices: Cloves, peppermint, star anise, oregano, sage, rosemary, thyme
- High-quality cocoa powder
- Nuts: chestnuts, hazelnuts, pecans, and almonds contain the highest amounts of polyphenols
- Seeds, specifically flaxseeds
- Vegetables such as artichoke, red onion, shallots, and spinach.
- Coffee and tea (black, green or ginger)
5. Sleep is a Critical Component in Blood Pressure Management
Research consistently supports a clear link between sleep and blood pressure. One 2018 study showed that when sleep dropped from seven to five hours per night, the risk for hypertension increased by 60%.
Insulin resistance is one of the crucial mechanisms linking sleep loss to high blood pressure, as there is evidence that even one night of short sleep can significantly impair your insulin sensitivity the following day. Over time, sleep loss can lead to insulin resistance and increase blood pressure in the same way as obesity. However, the good news is that achieving 7-9 hours of sleep per night can mostly reverse these effects.
Endothelial dysfunction is also a common trait of sleep loss, as inadequate sleep increases inflammation of your blood vessels. Sleep loss prevents the effective clearance of free radicals, which increases oxidative stress and negatively affects the expansion and contraction of blood vessels in response to blood pressure fluctuations.
Steps you can take to improve your sleep include:
- Keep a regular sleep-wake cycle that allows you to achieve 7-9 hours of sleep a night.
- Get regular daylight exposure. At least 30 minutes a day is ideal, preferably before noon.
- Ensure you have a cool, dark sleep environment.
- Avoid stimulants like caffeine or nicotine in the hours before bed.
- Take time to create a sleep routine, avoiding blue-light emitting devices, taking a bath or shower, alongside reading or meditation.
- In obese people, weight loss reduces blood pressure by increasing insulin sensitivity, enhancing the function and structure of your circulatory system, and improving fluid balance.
- Exercise helps you achieve healthy blood pressure by reversing insulin resistance, supporting weight loss, and increasing the growth of microvessels that carry blood around your body.
- Sodium and potassium affect your blood pressure by influencing fluid balance, and high sodium diets cause you to retain more fluid, while potassium helps you excrete excess sodium.
- Compounds in plant foods known as polyphenols act as antioxidants in the body and reduce blood pressure by preventing endothelial dysfunction and fighting oxidative stress.
- Sleep is an essential component in managing blood pressure as it helps increase insulin sensitivity and acts as an antioxidant.
- If you have high blood pressure, diet and lifestyle choices are two crucial tools to improving your health.
 GBD 2013 Risk Factors Collaborators (2015). Global, regional, and national comparative risk assessment of 79 behavioural, environmental and occupational, and metabolic risks or clusters of risks in 188 countries, 1990-2013: a systematic analysis for the Global Burden of Disease Study 2013. The Lancet. 5 386 (10010), pp. 2287-323.
 Centers for Disease Control and Prevention (CDC) (2019). Hypertension Cascade: Hypertension Prevalence, Treatment and Control Estimates Among US Adults Aged 18 Years and Older Applying the Criteria From the American College of Cardiology and American Heart Association’s 2017 Hypertension Guideline—NHANES 2013–2016Atlanta, GA: US Department of Health and Human Services.
 Clamp, L. D., et al. (2017). Enhanced insulin sensitivity in successful, long-term weight loss maintainers compared with matched controls with no weight loss history. Nutrition & diabetes, 7(6).
 DeMarco. V.G., Aroor. A.R, Sowers. J.R. (2004). The pathophysiology of hypertension in patients with obesity. National Review of Endocrinology. 10(6).
 Jia, G. et al (2015). Vascular stiffness in insulin resistance and obesity. Frontiers in physiology, 6, p. 231.
 DeMarco. V.G., Aroor. A.R, Sowers. J.R. (2004). The pathophysiology of hypertension in patients with obesity.
 DeMarco. V.G., Aroor. A.R, Sowers. J.R. (2004). The pathophysiology of hypertension in patients with obesity.
 Börjesson, M., et al. (2016). Physical activity and exercise lower blood pressure in individuals with hypertension: narrative review of 27 RCTs. British Journal of Sports Medicine, 50(6).
 Pedralli, M., et al. (2020). Different exercise training modalities produce similar endothelial function improvements in individuals with prehypertension or hypertension: a randomized clinical trial. Scientific Reports, 10(1).
 Gambardella, J., et al. (2020). Pathophysiological mechanisms underlying the beneficial effects of physical activity in hypertension. The Journal of Clinical Hypertension, 22(2).
 Gambardella, J., et al. (2020). Pathophysiological mechanisms underlying the beneficial effects of physical activity in hypertension.
 Schwingshackl, L., et al. (2018). Comparative effects of different dietary approaches on blood pressure in hypertensive and pre-hypertensive patients: A systematic review and network meta-analysis. Critical Reviews in Food Science and Nutrition, 59(16).
 Iqbal, S., Klammer, N. and Ekmekcioglu, C. (2019). The Effect of Electrolytes on Blood Pressure: A Brief Summary of Meta-Analyses. Nutrients, 11(6).
 Iqbal, S., Klammer, N. and Ekmekcioglu, C. (2019). The Effect of Electrolytes on Blood Pressure: A Brief Summary of Meta-Analyses.
 Godos, J., et al. (2019). Dietary Polyphenol Intake, Blood Pressure, and Hypertension: A Systematic Review and Meta-Analysis of Observational Studies. Antioxidants, 8(6).
 Schulz, E., Gori, T. & Münzel, T. (2011). Oxidative stress and endothelial dysfunction in hypertension. Hypertension Research, 34, pp. 665–673.
 Grandner, M., et al. (2018). Sleep Duration and Hypertension: Analysis of > 700,000 Adults by Age and Sex. Journal of Clinical Sleep Medicine, 14(6).
 Esther, D., et al. (2010). A Single Night of Partial Sleep Deprivation Induces Insulin Resistance in Multiple Metabolic Pathways in Healthy Subjects, The Journal of Clinical Endocrinology & Metabolism, 95(6).
 Aggarwal, B., et al. (2018). Effects of Inadequate Sleep on Blood Pressure and Endothelial Inflammation in Women: Findings From the American Heart Association Go Red for Women Strategically Focused Research Network. Journal of the American Heart Association, 7(12).