High Blood Pressure (Hypertension): What Is It and How Do You Control It?

Cathryn Bigham, Sara Exler, National Center for Health Research

High blood pressure often has no symptoms, but it is dangerous. That’s why it can be called “the silent killer.” Most doctor’s visits start with a nurse or technician taking your blood pressure because high blood pressure can lead to a heart attack, stroke, kidney failure, and death if not detected early and appropriately treated.[1]

High blood pressure (also called hypertension) affects almost 50% of adults in the United States, and only about 20% of people diagnosed with hypertension have their blood pressure under control.[2]

You’ve heard the words, but do you know what blood pressure is? Blood pressure is the force of blood against the arteries as the heart beats. It is measured with two numbers: systolic (the pressure when the heart beats) and diastolic (the pressure when the heart rests between beats). Blood pressure is usually written as systolic over diastolic like this: 120/80 mmHg.

Blood pressure is supposed to be taken after you’ve sat quietly and calmly for at least 5-10 minutes. When taken that way, blood pressure is considered normal if it is less than 120/80 mmHg. Between 120/80 and 129/80 mmHg is considered elevated, meaning it is not dangerous but you may be starting to develop high blood pressure. Hypertension or high blood pressure is divided into two stages. Stage One Hypertension is a systolic blood pressure of 130-139 mm Hg with diastolic at 80-89 mm Hg. Stage Two Hypertension is a blood pressure higher than 140/90 mm Hg. If your blood pressure is above 180/120 mmHg, this is a hypertensive crisis, and you should seek immediate medical care.[3] If your blood pressure reading is higher than normal, it is a good idea to sit quietly as possible for a few minutes after the reading, and try again to see if it is lower. That way, you and your doctor will know if you are able to substantially lower your blood pressure or if it is out of your control.

Blood Pressure Measures (mm Hg)
Normal less than 120/80
Elevated (120-129)/(<80)
High BP stage 1 (130-139)/(80-89)
High BP stage 2 more than 140/90
Hypertensive Crisis more than 180/120

These blood pressure guidelines were updated in 2017 and are the same across all age groups.[4] However, because the arteries stiffen as we age, our blood pressure will naturally get higher. It is common for adults 65 and older to sometimes have an elevated systolic blood pressure above 130 but the diastolic blood pressure remains normal (around 80 or less).[5] This can lead to shortness of breath, lightheadedness, and falls.[5]

What Causes High Blood Pressure?

People with family members with high blood pressure often develop high blood pressure as well, either because of their genes or their health habits. High blood pressure also is more common as you get older and for people with diabetes. Lack of physical activity, an unhealthy diet, being overweight, alcohol use, stress, and smoking also increases your chances of having high blood pressure.[6]

What You Should Do to Keep Your Blood Pressure in the Healthy Range?

 

  • Get enough sleep
  • Reduce stress
  • Eat more fruits, vegetables, and whole grains
  • Exercise
  • Drink less alcohol
  • Quit smoking

As this list shows, you can reduce your blood pressure by changing some of your habits. Improvements include maintaining a healthy diet, quitting smoking, limiting alcohol intake, exercising regularly, and controlling levels of stress.[7] Reducing stress not only helps reduce high blood pressure, but also helps alleviate many other health issues. Even sunshine can help; one 2014 study found that for those with mild hypertension, 30 minutes per day in the sun reduced blood pressure a small but significant amount, and overall blood pressure rates improved in the summer compared to the winter.[8]

Exercise

Regular exercise can significantly help lower your blood pressure. Different studies have shown that at least 30 minutes of moderate exercise 3 or 4 times a week can help lower blood pressure 4-9 mm Hg.[9] Getting exercise doesn’t have to mean spending all day at the gym. Simple changes such as parking further away and walking the rest of the way, taking the stairs instead of the elevators, taking a brisk walk around the neighborhood, and joining local fitness groups are all ways to start increasing your activity levels. Don’t try to do too much too suddenly; work slowly and gradually increase your exercise intensity. Finding a particular type of movement you enjoy will help you better stay on track with a regular exercise routine. Always talk with your doctor before starting a new exercise routine.

Salt

Eating less salt to reduce your high blood pressure mainly works in combination with other lifestyle changes, such as a better diet and more exercise.[10] Less salt has been found especially effective in lowering high blood pressure in African Americans, people middle aged and older, and people who are overweight.[11] The previously accepted recommended sodium intake was 1500 mg per day (less than half a teaspoon of salt) for those with high blood pressure.[12] Processed foods are very high in salt, making up more than 75% of our salt intake. Most salt in your diet may be from foods you do not think of as salty, such as bread, cold cuts and processed meats, pizza, soup, cheese, pasta dishes, chicken dishes, sauces like ketchup and soy sauce, and frozen food.[13] The easiest way to reduce your salt consumption is to cook your own food from fresh ingredients, because even if you add salt it is likely to be much less than in processed foods. In fact, studies show that when people are served low sodium foods but are allowed to add salt from a salt shaker, most people only add back 20% of the sodium removed from their food.[14] To lower your salt intake without sacrificing taste, consider experimenting with different spices and seasonings like garlic, lemon juice, ginger, cilantro, pepper, rosemary, or sage.

Monitoring Blood Pressure at Home

If your doctor recommends you monitor your blood pressure at home, there are a few good tips you should follow. Buy a good quality digital home blood pressure monitor. Make sure the cuff is the right size; different size cuffs are available to buy and the wrong size cuff will give inaccurate results. Take your home blood pressure monitor to the doctor and have it checked to make sure it is accurate, and to make sure you are using it correctly. Do not take your blood pressure for 30 minutes after eating, exercising, smoking, or drinking caffeine.[15] As noted above, you should sit quietly doing nothing for 5-10 minutes prior to measuring your blood pressure, and keep your arm still and relaxed while it is being measured. Monitoring your blood pressure at home is a good way to track any changes made by either better habits, medicine, or both. A 2013 study found that people who monitored their blood pressure at home were significantly more likely to have their blood pressure under control after six months than those who did not.[16]

Medicines for Treating High Blood Pressure

If you are diagnosed with high blood pressure that you can’t control with diet and exercise, you will likely be prescribed one or a combination of the medicines below. A recent study found that taking blood pressure medication in the evening can improve overnight blood pressure and also help a person’s wake-sleep cycle by helping them sleep at night and feel more energetic during the day.[17] Taking blood pressure medication at night is as effective during the day as taking it in the morning. Discuss this with your cardiologist before switching the time of day you take your medications. For many years, doctors advised African Americans to take calcium channel blockers or thiazide diuretics instead of ACE inhibitors or ARBS. However, more recent research indicates that it is generally better to choose whichever medication is most effective with fewer side effects for the individual patient, rather than make decisions based on race.[18]

Blood Pressure Medications Description [19]
Thiazide-Type Diuretic Diuretics are also known as “water pills” because they help flush excess water and sodium from the body. Ex. Hydrochlorothiazide (HCTZ)
Calcium Channel Blocker (CCB) A CCB helps prevent calcium from entering the muscle cells in the arteries. This causes blood vessels to relax and blood pressure lowers. Ex. Amlodipine
Angiotensin-Converting Enzyme Inhibitor (ACEI) Angiotensin converting enzyme (ACE) inhibitors prevent the formation of angiotensin II, which narrows blood vessels. The blood vessels relax and it lowers blood pressure. Ex. Lisinopril
Angiotensin Receptor Blocker (ARB) ARBS block blood vessels from angiotensin II. As a result, the vessels become wider and blood pressure goes down. Ex. Valsartan

Sodium nitroprusside (the brand name is Nitropress) is a drug used to treat life-threatening hypertension. However, this drug can prevent oxygen from getting to the rest of your body, which can be deadly.[20] Therefore, it should only be used when hypertension is also life-threatening, and only at the dose and length of time absolutely necessary.

Bottom Line

High blood pressure is a common problem for American adults, and most people with high blood pressure have no symptoms. That’s why it is called “the silent killer.” If you have high blood pressure (hypertension), it’s important to establish a treatment plan with your doctor. Medicine can be very helpful, but it is very important to change some of your health habits, such as lowering salt intake, a healthier diet, quitting smoking, increasing exercise, and stress control.  If those strategies don’t work, you may need medication as well.

For more information about blood pressure medication, you can read this article.

All articles are reviewed and approved by Dr.Diana Zuckerman and other senior staff.

 

References

  1. Evidence-Based Guideline for the Management of High Blood Pressure in Adults: Report From the Panel Members Appointed to the Eighth Joint National Committee (JNC 8). JAMA. 2013;():. doi:10.1001/jama.2013.284427.
  2. CDC. Hypertension Prevalence, Awareness, Treatment, and Control Among Adults Age 18 and Older: United States, August 2021–August 2023. National Center for Health Statistics. doi:10.15620/cdc/164016
  3. May 17 LR, 2024. Understanding Blood Pressure Readings. www.heart.org. Accessed July 24, 2025. https://www.heart.org/en/health-topics/high-blood-pressure/understanding-blood-pressure-readings
  4. LeWine H. Reading the new blood pressure guidelines. Harvard Health. April 1, 2018. Accessed July 24, 2025. https://www.health.harvard.edu/heart-health/reading-the-new-blood-pressure-guidelines
  5. High Blood Pressure and Older Adults. National Institute on Aging. October 1, 2022. Accessed July 24, 2025. https://www.nia.nih.gov/health/high-blood-pressure/high-blood-pressure-and-older-adults
  6. CDC. High Blood Pressure Risk Factors. High Blood Pressure. January 16, 2025. Accessed July 24, 2025. https://www.cdc.gov/high-blood-pressure/risk-factors/index.html
  7. Evidence-Based Guideline for the Management of High Blood Pressure in Adults: Report From the Panel Members Appointed to the Eighth Joint National Committee (JNC 8). JAMA. 2013;():. doi:10.1001/jama.2013.284427.
  8. Irradiation of Human Skin Vasodilates Arterial Vasculature and Lowers Blood Pressure Independently of Nitric Oxide Synthase. Journal of Investigative Dermatology (20 January 2014) | doi:10.1038/jid.2014.27
  9. Effect Of Changing Levels Of Physical Activity on Blood-pressure and Haedonymics in Essential Hypertension The Lancet – 30 August 1986 ( Vol. 328, Issue 8505, Pages 473-476 ) DOI: 10.1016/S0140-6736(86)90354-5.
  10. Is Salt Dietary Reduction Worth the Effort?, The American Journal of Medicine, Volume 125, Issue 5, May 2012, Pages 433-439, ISSN 0002-9343, http://dx.doi.org/10.1016/j.amjmed.2011.10.023.
  11. alt and Hypertension: Is Salt Dietary Reduction Worth the Effort?, The American Journal of Medicine, Volume 125, Issue 5, May 2012, Pages 433-439, ISSN 0002-9343, http://dx.doi.org/10.1016/j.amjmed.2011.10.023.
  12. Urinary Sodium and Potassium Excretion and Risk of Cardiovascular Events. JAMA. 2011;306(20):2229-2238. doi:10.1001/jama.2011.1729.
  13. Food Categories Contributing the Most to Sodium Consumption—United States, 2007–2008, February 10, 2012 / 61(05);92-98.
  14. Strategies to reduce sodium intake in the United States. Henney JE, Taylor CL, Boon CS, eds. Washington, DC: The National Academies Press; 2010
  15. Systemic hypertension: mechanisms and diagnosis. In: Bonow RO, Mann DL, Zipes DP, Libby P, eds. Braunwald’s Heart Disease: A Textbook of Cardiovascular Medicine. 9th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 45.
  16. Effect of Home Blood Pressure Telemonitoring and Pharmacist Management on Blood Pressure Control: A Cluster Randomized Clinical Trial. JAMA. 2013;310(1):46-56. doi:10.1001/jama.2013.6549
  17. Ye R, Yang X, Zhang X, et al. Morning vs Bedtime Dosing and Nocturnal Blood Pressure Reduction in Patients With Hypertension: The OMAN Randomized Clinical Trial. JAMA Netw Open. 2025;8(7):e2519354. doi:10.1001/jamanetworkopen.2025.19354 
  18. Apeles L. Race-Based Prescribing for Black People with High Blood Pressure Shows No Benefit | UC San Francisco. January 18, 2022. Accessed July 24, 2025. https://www.ucsf.edu/news/2022/01/422151/race-based-prescribing-black-people-high-blood-pressure-shows-no-benefit
  19. Nov 7 LR, 2024. Types of Blood Pressure Medications. www.heart.org. Accessed July 24, 2025. https://www.heart.org/en/health-topics/high-blood-pressure/changes-you-can-make-to-manage-high-blood-pressure/types-of-blood-pressure-medications
  20. FDA. Pediatric Postmarketing Pharmacovigilance and Drug Utilization Review. DHHS; 2017.