scaleA healthy lifestyle — which means not smoking, losing excess weight, eating nutritious foods, and exercising regularly — is the cornerstone for preventing and treating hypertension. Nutrition-wise, one of the biggest no-no’s in the typical American diet is the overabundance of sodium (with chloride, one of two components of table salt). Too much sodium helps usher in high blood pressure and damages arteries, which is why the salt story warrants an entire separate chapter in this report (see “Special section: Conquering your salt habit”).

Healthy habits are the best approach for bringing prehypertensive blood pressures (120/80–139/89 mm Hg) into a safe range. In addition, people with stage 1 hypertension (140/90–159/99 mm Hg) who don’t have any other health conditions can often try making lifestyle changes before resorting to medications. By making a diligent effort to improve your diet and fitness, you can very likely reduce your blood pressure numbers — even without popping a pill (see Table 2).

A study published in the Journal of the American Medical Association lends support to this strategy. Researchers found that many people with hypertension were able to stop taking their blood pressure medications if they reduced their salt intake and lost weight. The trial included 975 volunteers, ages 60 to 80, who were taking blood pressure drugs. The 390 normal-weight participants received either counseling to reduce their salt intake or no dietary advice. The other 585 people, who were overweight, were divided into four equal groups. People in the first three groups were asked respectively to lose weight, reduce salt consumption, or do both. The fourth group received no special instructions. After three months, the researchers began to gradually withdraw the subjects from their blood pressure drugs.

More than two years later, the people assigned to both weight loss and salt reduction were only about half as likely to have high blood pressure, require an antihypertensive drug, or have cardiovascular problems as those who made no changes. People who only lost weight or reduced salt were each a third less likely to have high blood pressure, require an antihypertensive drug, or have cardiovascular problems than those who didn’t make any lifestyle changes.

Even if you need to use antihypertensive drugs to control your blood pressure, you should still adopt healthy habits. The lifestyle changes described in the following sections can substantially improve your blood pressure. For example, diet and exercise are an essential part of treatment because they help medications control your blood pressure, making it possible for you to get good results with a lower dosage.

Table 2: Keeping score

Lifestyle change What to do Potential reduction in systolic blood pressure
Lose weight Reach and maintain a normal body mass index 5–20 mm Hg for every 22 pounds lost
Adopt the DASH diet Eat plenty of fruits and vegetables, choose low-fat dairy products, and reduce total fat consumption 8–14 mm Hg
Reduce salt Consume no more than 2,300 mg of sodium a day (about 6,000 mg of salt) 2–8 mm Hg
Exercise regularly Get at least 30 minutes of moderate aerobic exercise on all or most days of the week 4–9 mm Hg
Limit alcohol Have no more than two drinks per day if you’re male, or one drink per day if you’re female 2–4 mm Hg
Quit smoking There is no safe amount of cigarette smoking; if you smoke, try to quit 2–8 mm Hg*
*Estimate based on clinical experience.Source: Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure, May 2003.

 

Quit smoking

When it comes to heart disease and blood pressure, smoking packs a devastating wallop. Nicotine raises your blood pressure, lowers “good” HDL cholesterol, reduces your body’s supply of oxygen, and makes blood clots more likely.

Quitting is tough because smoking cigarettes is psychologically and physically addictive. Smoking cessation programs primarily address the psychological facets of addiction by helping participants change ingrained behaviors. Nicotine replacement systems — such as patches, chewing gum, and nasal sprays — target physical craving by delivering the addictive substance in another form, allowing the user to taper off gradually and minimizing withdrawal symptoms. According to the American Lung Association, using a nicotine replacement product and participating in a smoking cessation program doubles your chances of successfully quitting.

Quitting offers enormous benefits. Within hours of stopping smoking, your heart rate and blood pressure decrease. Within a year of quitting, your heart disease risk is cut in half. Within 15 years of giving up smoking, your risk of heart disease is close to that of nonsmokers.

Tips for quitting

Get ready. Set a quit date; get rid of all cigarettes and tobacco products from your home, office, and car; don’t let people smoke around you; and once you quit, don’t smoke — not even a puff!

Find support and encouragement. Tell everyone you are going to quit and ask them not to smoke around you; talk to your health care provider; and get individual, group, or telephone counseling. A 2008 study in The New England Journal of Medicine suggests that spouses, friends, co-workers, and other direct contacts have a huge influence on quitting smoking. Once one person stops, others around the quitter have a better chance of quitting, too. Sometimes it helps to quit with a friend or family member so that you can support each other through the process.

Identify and avoid your triggers. Many smokers link having a cigarette with activities like finishing a meal or drinking coffee or alcohol. Breaking these links is an essential part of a stop-smoking try. Counseling and social support can help you identify and find new ways of dealing with these triggers.

Learn new skills and behaviors. Try to distract yourself by taking a walk or getting busy with a hobby or task; reduce your stress by exercising or taking a hot bath; plan something enjoyable to do each day; drink a lot of water and other nonalcoholic fluids.

 

Attain a Healthy Weight

Not only can being overweight raise your blood pressure (see “Obesity”), it can also increase your risk for diabetes, arthritis, sleep apnea, and some cancers. Achieving and maintaining a healthy weight is an important step in fighting these and many other illnesses.

People with hypertension who are more than 10% over their ideal weight may be able to reduce their blood pressure by weight loss alone. According to the JNC report, you can reduce your systolic blood pressure by 5 to 20 mm Hg for every 22 pounds you lose . A smaller weight loss can have an effect, too. Losing as few as 10 pounds can reduce your blood pressure.

Calories count

How do you go about attaining a healthy weight? It seems that every month brings a new book on the subject boasting some surefire method and professing to debunk its predecessors’ claims. Eat fewer carbohydrates, claims one. Limit fat, counters another. Become a vegetarian, advocates yet another. But for all the hype, the simple truth is this: your body weight is a matter of calories in versus calories out — always has been, always will be. To lose weight, you need to burn more calories than you consume. You can do so either by reducing your caloric intake or by increasing your physical activity. It’s a good idea to do a little of both.

Eating fewer calories doesn’t necessarily mean eating less. “Caloric density” is a way to describe the number of calories contained in a food when its portion size is taken into consideration. A cookie, for example, can pack a lot of calories into a very small amount of food, and therefore has a high caloric density. On the other hand, you might have to eat an entire plate of steamed vegetables to equal the calorie count of that one cookie. Vegetables have a low caloric density. In general, fresh, whole, natural foods have a low caloric density, which means that you can fill up on them without consuming too many calories. Snack on carrot sticks or air-popped popcorn instead of potato chips or crackers. Choose water or unsweetened iced tea over sugary soft drinks. Cut a little here and a little there — you may hardly know you’re dieting.

The first important step to losing weight is to figure out how many calories your body requires to maintain its current weight. To do so, do a simple calculation: multiply your current weight in pounds by 15 — that’s roughly the number of calories per pound of body weight needed to maintain your current weight if you are moderately active. Moderately active means getting at least 30 minutes of physical activity a day in the form of exercise (walking at a brisk pace, climbing stairs, or active gardening).

Here are some examples:

  • If you weigh 150 pounds, 150 × 15 = 2,250 calories for weight maintenance.
  • If you weigh 200 pounds, 200 × 15 = 3,000 calories for weight maintenance.

 

Losing the weight

One pound of body fat is equal to 3,500 calories that you consumed but didn’t burn. To lose weight, you’ll need to create a “calorie deficit”: by eating fewer calories than you require, by burning more calories than you usually do, or some combination of the two. For example, if it takes 2,365 calories a day to maintain your weight, you might consume 1,865 a day, a 500-calorie reduction. After seven days, you’ll have lost a total of 3,500 calories, and should be a pound lighter. Or if you want to be less aggressive, you can reduce an average of 250 calories a day and lose that pound after two weeks. (As your weight changes, you’ll need to continually re-evaluate your calorie needs.)

Or maybe you don’t want to restrict your calories quite so much. If that’s the case, you can reduce your daily calories by only 100 and increase your physical activity in order to burn an extra 150 calories. The result is the same: you will have created an overall 250-calorie daily deficit, and lose a pound after two weeks.

As you can see, losing weight involves a little bit of math and a little bit of willpower. Small, consistent steps, taken at a pace that’s right for you, are the key to achieving your goal.

 The DASH Diet

DASH stands for Dietary Approaches to Stop Hypertension, a diet developed by nutritionists to lower blood pressure. Put to the test in two large clinical trials — the first described in The New England Journal of Medicine in 1997 — the DASH diet passed with flying colors. For many people who follow it, the diet is enough to keep blood pressure in the normal range without medicine.

Key features of the DASH diet include plenty of fruits, vegetables, and whole grains; several servings daily of low-fat dairy products; some fish, poultry, dried beans, nuts, and seeds; and minimal red meat, sweets, and sugar-laden beverages. This mix of foods provides ample calcium, potassium, magnesium, vitamins, and fiber while limiting saturated fat, cholesterol, and sodium (see Table 3).

Table 3: The DASH eating plan

The DASH eating plan shown below is based on 2,000 calories a day. The number of daily servings in a food group may vary from those listed depending on your caloric needs. To learn more about the DASH diet, visit www.health.harvard.edu/122.

Food group Examples Servings
Grains and grain products 1 slice bread
1 cup ready-to-eat cereal*
½ cup cooked rice, pasta, or cereal
7–8 per day
Vegetables 1 cup raw leafy vegetable
½ cup cooked vegetable
6 ounces vegetable juice
4–5 per day
Fruits 1 medium fruit
¼ cup dried fruit
½ cup fresh, frozen, or canned fruit
6 ounces fruit juice
4–5 per day
Low-fat or fat-free dairy foods 8 ounces milk
1 cup yogurt
1½ ounces cheese
2–3 per day
Lean meats, poultry, and fish 3 ounces cooked lean meats, skinless poultry, or fish 2 or less per day
Nuts, seeds, and beans ½ cup or 1½ ounces nuts
1 tablespoon or ½ ounce seeds
½ cup cooked dry beans
4–5 per week
Fats and oils** 1 teaspoon soft margarine
1 tablespoon low-fat mayonnaise
2 tablespoons light salad dressing
1 teaspoon vegetable oil
2–3 per day
Sweets 1 tablespoon sugar
1 tablespoon jelly or jam
½ ounce jelly beans
8 ounces lemonade
5 per week
*Serving sizes vary between ½ cup and 1¼ cups. Check the product’s nutrition label.**Fat content changes serving counts for fats and oils: for example, 1 tablespoon of regular salad dressing equals 1 serving; 1 tablespoon of a low-fat dressing equals ½ serving; 1 tablespoon of a fat-free dressing equals 0 servings.

Researchers do not attribute the blood pressure reductions of the DASH trial to any single nutrient. Compared with the typical American diet, the DASH eating plan has a relatively higher calcium content and less salt, total fat, saturated fat, and cholesterol. It also has 173% more magnesium, 150% more potassium, 240% more fiber, and 30% more protein.

In the original DASH study, 459 volunteers were randomly assigned one of three diets. One was based on what most Americans eat, with 37% of calories from fat. The second was a similar regimen with fruits and vegetables added. The third was a “combination” diet (the DASH diet), containing 27% of calories from fat, plus plenty of fruits and vegetables, whole grains, low-fat or nonfat dairy products, and small amounts of meat, fish, poultry, and nuts.

After following the DASH plan for eight weeks, participants with hypertension enjoyed average reductions of 11.4 mm Hg in systolic pressure and 5.5 mm Hg in diastolic pressure. These results are comparable to the effects of some antihypertensive drugs. Participants with borderline high blood pressure experienced improvements as well, suggesting that the DASH diet may keep some people from developing hypertension in the first place. The second diet, which was higher in fats but also rich in fruits and vegetables, also lowered blood pressure, although not as much as the DASH plan. All reductions occurred without people changing their salt intake, alcohol consumption, or weight — factors known to influence blood pressure.

A follow-up analysis of the trial’s results found that the DASH diet reduced blood pressures in virtually all groups tested regardless of such factors as age, sex, race, and hypertension status. Its effects were most pronounced, though, in African Americans and people with hypertension.

In fact, the results were so promising that the federal guidelines recommend that all Americans — not just those with hypertension — follow the DASH diet. A follow-up study, the DASH-Sodium trial, compared a typical American diet (the control diet) with the DASH diet at different sodium levels (3,300, 2,400, or 1,500 mg per day). People with high blood pressure who ate the DASH diet at the lowest sodium level had an average systolic pressure reading 11.5 mm Hg lower than participants eating the control diet at the highest sodium level (see “A low-salt DASH diet helps prevent age-related blood pressure rise”).

Still more support for DASH came from an assessment from the Harvard-based Nurses’ Health Study. Among nearly 90,000 female nurses whose diets, other habits, and health were followed for 24 years, those whose eating patterns most closely resembled the DASH diet had fewer heart attacks and strokes and were less likely to have died of heart disease compared with women reporting average American diets, as described in a 2008 article in Archives of Internal Medicine.

Combining a structured weight-loss program with the DASH diet can drop your blood pressure even more than DASH alone, according to another report in Archives of Internal Medicine, published in 2010. The study included 144 overweight or obese people with hypertension who weren’t taking any blood pressure–lowering drugs. About a third of them followed the DASH diet along with a weight-management program. Another third did DASH alone, and the other third followed their regular diet. The weight-management program relied on a strategy known as Appetite Awareness Training, which teaches people to identify their natural hunger and fullness cues to help them learn when and how much to eat. The program also included supervised exercise sessions that featured biking, walking, or jogging (including a warm-up and cool-down) for 45 minutes, three times a week.

After four months, the average blood pressure readings for the DASH-plus-weight-management group dropped by 16.1/9.9 mm Hg, compared with 11.2/7.5 for the DASH-only group and 3.4/3.8 for the control group. As the authors point out, the blood pressure reductions seen in the weight-management group are similar to what doctors would expect from a high dose of an antihypertensive drug.

A low-salt DASH diet helps prevent age-related blood pressure rise

image

A low-sodium DASH diet may prevent or reverse the typical rise in blood pressure that occurs as people grow older, according to findings from the DASH-Sodium trial. The study included just over 400 people, with roughly half following a typical American diet (the control group) and half following the DASH diet for three months. During that time, both groups ate three versions of their assigned diet with different sodium levels: high (3,500 mg), intermediate (2,300 mg), and low (1,200 mg) for a month each. Researchers also grouped the volunteers by age; there were between 45 and 58 people in each of the four age ranges shown in the graph.

The red line shows the average systolic blood pressure reading for the control group at the end of the high-sodium intake phase. The black line shows the average systolic blood pressure reading for the DASH group at the end of the low-sodium intake phase. When people followed the low-sodium DASH diet, average systolic blood pressures stayed around 125 mm Hg, even in the oldest age group, while the values for those following the high-sodium typical diet rose close to the range of stage 1 hypertension for the oldest age group.

Source: New England Journal of Medicine (2010), Vol. 362, pp. 2102-12.