The DASH Diet - A blood pressure diet: This article is about diet and choosing foods to lower high blood pressure:
- Getting the low down on the DASH diet and salt reduction
- Using weight loss to get the blood pressure down
- Checking out the other diets and seeking assistance
You are what you eat, the old saying goes. But it’s truer than ever with high blood pressure. Weight loss, a well-balanced diet, and salt intake reduction can lower blood pressure. These approaches, however, haven’t successfully kept blood pressure down in most patients. A new approach is needed: a blood pressure diet. The DASH diet is exactly this - an eating plan to treat hypertension.
In this article, you discover a new approach to healthy eating. We explain how it developed and proved effective, and we show you how to use it to reduce your blood pressure, no matter what your level is now. For people who want to reduce weight for whatever reason, we also provide a sensible, balanced program to help you get there.
Following the DASH diet to lower your blood pressure
Based on study results at four major medical centers in the United States, the “Dietary Approach to Stop Hypertension” (DASH) diet was published in the New England Journal of Medicine (April 1997). All patients on the DASH diet successfully reduced their systolic and diastolic blood pressure (see article 2 for more about these terms). The Table 1 below shows the average reduction in millimeters of mercury for the systolic blood pressure (SBP) and the diastolic blood pressure (DBP) for the various groups that followed the DASH diet.
|Group||Systolic BP||Diastolic BP|
|No high BP||3.5||2.2|
They achieved this reduction without special foods, food supplements, drugs, or weekly meetings. Furthermore, they achieved it without emphasizing weight loss by reducing kilocalories, without insisting on salt reduction, and without demanding exercise.
Are you intrigued? In the following sections, we describe the creation of the DASH diet and show you how to get started.
Leading up to DASH
DASH was created when doctors noted that vegetarians generally have lower blood pressure and a lower incidence of coronary heart disease (see article 5) and strokes (see article 7) than non-vegetarians. The reason isn’t exactly clear. However, the big difference between vegetarians and non-vegetarians is that the former eat more fruits and vegetables than the latter. They also, of course, eat no meat and generally have less cholesterol and saturated fat in their pattern of eating.
Because a vegetarian program isn’t a practical recommendation for the American public, scientists attempted to replicate the vegetarian program while permitting some meat. They looked for the substances in the food that could explain the fall in blood pressure.
The scientists recognized that a nutritional program with more fruits and vegetables has more potassium, which definitely affects blood pressure. The higher the potassium, the lower the blood pressure. So the increased potassium may be a partial explanation for the lower blood pressure, but it’s not the entire story because similar amounts of potassium don’t lower the blood pressure to the same extent unless salt is also reduced.
Note: The other important nutrients in vegetables and fruits are calcium and magnesium. However, studies haven’t shown that these minerals lower blood pressure. And although fat intake reduction and the increase in fiber may lower blood pressure, researchers haven’t determined their role in blood pressure control either.
The people who designed DASH decided that the mix of different nutrients may be responsible for the blood-pressure-lowering effect. To test their theory, they tried the combination on a large group of people, with an emphasis on African Americans, who have the highest rate of high blood pressure in the United States (as we note in article 3).
Proving the value of DASH
The study involved 459 people with a systolic blood pressure under 160 mm Hg and a diastolic blood pressure of 80 to 95 mm Hg. In addition, the participants
- Were all older than 22
- Took no medications for high blood pressure
- Had to stop taking all vitamins and food supplements
- Couldn’t drink more than 14 drinks of wine or other spirits per week
- Couldn’t have poorly controlled diabetes, high blood fats, or a body mass index greater than 35
At the beginning of the study,
- Two out of three participants were African Americans.
- The mean age was 44 years.
- The average blood pressure of the group was 132/85 mm Hg with 29 per- cent having mild high blood pressure.
- Participants were mildly overweight with an average body mass index of 27.
- Twenty-seven percent were smokers.
For three weeks, the participants closely followed a common American diet (high in fats and total calories); then they were randomly broken into three groups:
- One group continued the usual American diet.
- The second group received a diet rich in fruits and vegetables.
- The third group was given DASH.
In addition, participants were given sufficient food so that they didn’t lose weight, and they didn’t have a decrease in salt intake. The diets continued for eight weeks.
After only two weeks, the usual diet group showed no change in blood pressure while the fruits-and-vegetables group reduced their blood pressures. But the DASH group had the greatest reduction in blood pressure, and they sustained this reduction for the entire study.
The average reduction in the DASH group’s blood pressure was 6/3 mm Hg, but the best results were among the people with the highest blood pressures — 11/6 mm Hg.
Since the DASH study, other studies have accomplished the same excellent results using DASH, whether in an academic setting or in a primary-care out-patient practice. Some of these studies have shown other beneficial effects of DASH. For example:
- DASH lowered total blood cholesterol and low-density lipoprotein (LDL or bad) cholesterol.
- Blood levels of homocysteine, a substance associated with higher levels of coronary heart disease, were lowered.
Because most high blood pressure patients have mild stage 1 high blood pressure (140 to 159 mm Hg for systolic blood pressure or 90 to 99 mm Hg for diastolic blood pressure, whichever is higher) and most illnesses and deaths occur in that group, the extent of DASH’s effects can have a significant impact on the health of Americans, especially those most at risk from high blood pressure.
DASH-Sodium, a second study that used various levels of sodium with the DASH program, showed that the lowest sodium level (1,500 mg daily) lowered blood pressure even more.
Getting with the program
The DASH program is usually based on a 2,000-kilocalorie-a-day diet. In the following sections, I provide you with the foods and servings in the program, sample menus, and tips for getting started and sticking with it.
If you find that following DASH is too difficult, don’t hesitate to ask your doctor for a referral to a dietitian. The DASH diet is a blood pressure diet.
Specific foods and servings
The 2,000-kilocalorie DASH eating plan has the following foods and servings. If you need fewer kilocalories to maintain your weight, take the lower number of servings; if you need more kilocalories, take the higher number of servings. (See the later section “Reducing Your Weight to Lower Blood Pressure” for more information on determining the number of kilocalories you need.)
- 7 to 8 servings of grains and grain products daily
A serving is 1 slice of bread, 1⁄2 bagel, 1⁄2 cup dry cereal, 1⁄2 cup cooked rice, pasta, or other cereal.
- 4 to 5 servings of vegetables daily
A serving is 1 cup of raw, leafy vegetables, 1⁄2 cup cooked vegetables, 6 ounces vegetable juice.
- 4 to 5 servings of fruit daily
A serving is 6 ounces of fruit juice, 1 medium fruit, 1⁄2 cup dried fruit, 1 ⁄2 cup of fresh, frozen, or canned fruit.
- 2 to 3 servings of low-fat or nonfat dairy products daily
A serving is 1 cup 1-percent milk, 1 cup low-fat yogurt, and 11⁄2 ounces non fat cheese.
- 2 or fewer servings of meats, poultry, or fish daily
A serving is 3 ounces of cooked lean meat, fish, or poultry.
- 2 + 1⁄2 servings of fats daily
A serving is 1 teaspoon oil, butter, margarine, mayonnaise, or 1 tablespoon regular or 2 tablespoons light salad dressing.
- 4 to 5 servings of nuts, seeds, or legumes per week
A serving is 1⁄3 cup nuts, 2 tablespoons seeds, 1⁄2 cup cooked legumes, or 3 ounces tofu.
- 5 servings of sweets per week including 1 tablespoon sugar, 1 tablespoon jelly or jam, 1⁄2 ounce jelly beans, or 8 ounces of lemonade.
Examples of good food choices in each group include:
- Grains and grain products: English muffins, high-fiber cereals, oatmeal, pita bread, and whole wheat breads
- Vegetables: Artichokes, broccoli, carrots, collards, green beans, kale, peas, potatoes, spinach, squash, sweet potatoes, tomatoes, and turnip greens
- Fruits: Apples, apricots, bananas, dates, grapes, oranges, orange juice, grapefruit, grapefruit juice, mangos, melons, peaches, pineapples, prunes, raisins, strawberries, and tangerines
- Dairy products: Buttermilk — skim or low-fat; cheese — non fat and part- skim mozzarella; milk — skim or 1-percent; yogurt — non fat or low-fat
- Fish, meats, and poultry: Lean meats, poultry without skin, and no frying or sautéing
- Nuts, seeds, and legumes: Almonds, mixed nuts, peanuts, peanut butter, and walnuts; sesame or sunflower seeds; garbanzo beans, kidney beans, navy beans, pinto beans, lentils, split peas, and tofu
To make up your daily nutrition, Table 2 shows a sample menu.
|3 grains||1 meat||1 meat||1 fruit|
|1 dairy||1 dairy||3 grains||1 grain|
|2 fruits||1 grain||3 vegetables||1 nuts|
|1 fat||1 fat||1 1/2 fat servings|
|1 fruit||1 fruit|
Eat a snack once daily.
Fill your own menu out following Table 3, or plan an entirely different day of meals, as Table 4 shows.
|1 cup corn flakes||2 oz chicken||3 oz salmon||1 medium apple|
|1 cup 1% milk||1/2 oz low fat cheddar||1 cup rice||1 slice wheat bread|
|1 banana||1 pita bread||1 cup squash||1/3 cup pecans|
|1 slice wheat toast||1 tsp margarine||1 cup spinach|
|1 tbsp jam||1 cup raw carrots||1 tbsp light Italian dressing|
|6 oz apple juice||1 orange||1 1/2 oz low fat Jack cheese|
|1 tsp margarine|
|1 cup prune juice||2 oz lean beef||3 oz trout||1 orange|
|1 cup oatmeal||1 tsp BBQ sauce||1 cup brown rice||1 oz dried fruit|
|1 slice whole wheat||1 roll||1 cup three-bean salad||2 tbsp sunflower seeds|
|1 tsp margarine||1 cup boiled potatoes||1 tbsp low-fat dressing|
|1 cup 1% milk||low-fat cheddar||1 1/2 oz corn muffin|
|1 banana||1 cup lettuce salad||1 tsp margarine|
|1 tbsp low-fat dressing||1 cup spinach|
|1 cup cranberry juice|
Helpful hints and resources
These suggestions can make the diet easier:
- Don’t try to change all at once. Gradually reduce your meats and increase your fruits and vegetables.
- Increase fruit and vegetable servings by having two at each meal and two for a snack.
- If you’re lactose intolerant, take lactase pills with the dairy foods or buy lactose-free milk.
- Use the percent Daily Values on food labels to pick the foods that are lowest in saturated fats, total fats, cholesterol, and salt.
- Reduce your fats so you’re eating half your normal intake; emphasize vegetable fats over animal fats.
- Avoid soda, alcohol, and other sugar-sweetened drinks.
- Use fruits as desserts.
- Instead of meat, fish, or poultry, make grains (like pasta and rice), beans, and vegetables the center of the meal.
The government has a booklet about the DASH diet at www.nhlbi.nih.gov/health/public/heart/hbp/dash/. Other valuable sources of information about DASH include the following:
- DASH Diet Eating Plan at dashdiet.org/
- DASH, A Diet for All Diseases at www.cspinet.org/nah/dash.htm
- DASH Diet for Health at www.dashforhealth.com/
- DASH Diet Recipes at www.mayoclinic.com/health/dash-diet-recipes/RE00089
Recent reports from Harvard Medical School (Journal of the American Medical Association, November 2005) suggest that — in place of the carbohydrates like grains, cereals, and breads in the DASH diet — you can substitute protein (half from vegetable sources like beans, nuts, peas, seeds, and soy products) or monounsaturated fats (like grape seed oil, olive oil, avocado, almonds, cashews, hazelnuts, pumpkin seeds, and sesame seeds). The result is a further lowering of blood pressure and a positive effect on the fats in the blood (cholesterol), thereby reducing risk of a heart attack.
To find specific substitutions, go to www.omniheart.org/OmniDiets.pdf. You can alter your diet to include the food you prefer and still lower your blood pressure.
Reducing salt as you DASH
Article 10 tells you all about salt and high blood pressure. The bottom line is this: The less salt in your diet, the lower your blood pressure. If you want to combine DASH with low salt, here are some suggestions:
- Buy products that have reduced sodium or no salt added on their labels.
- Use herbs, spices, a little wine, lemon, lime, or vinegar instead of salt to flavor your food.
- Leave the salt shaker in the kitchen, away from the table, to help you fight the urge to add more salt when eating.
- Eat more unprocessed foods — Mother Nature knows what she’s doing!
- Avoid high-salt condiments like soy sauce, teriyaki sauce, and monosodium glutamate (MSG).
- Reduce your intake of foods in brine and mustard, salt-cured foods, horseradish, ketchup, and Worcestershire sauce.
- Eat fruit and vegetable snacks instead of salty snack foods.
- Avoid salty foods when eating out.
Reducing Your Weight to Lower Blood Pressure
The fatter you are, the higher your blood pressure. More than 50 percent of the population is now overweight or obese as defined by the body mass index (BMI). In the following sections, you can calculate your BMI and find out whether your weight falls within the acceptable weight range for your height. You can also calculate the number of kilocalories you need to lose or maintain weight. If you do need to lose weight, I show you how to modify your diet to meet your new caloric needs.
For every 2.2 pounds of weight loss, your blood pressure drops by 1 mm of mercury systolic and 1 mm of mercury diastolic. In other words, if your blood pressure has been 135/85 and you lose 11 pounds, your blood pressure will fall to 130/80.
Calculating your ideal weight
In order to use weight loss to lower your blood pressure, you need to know your ideal weight. If you’re already within the correct range of weights for your height, further weight loss will probably not lower your blood pressure much more. However, if you’re overweight or obese, weight loss to your ideal range will significantly lower your blood pressure. Based on studies of many healthy men and women, you can determine your ideal weight range in the following manner:
- If you’re a woman, give yourself 100 pounds for being 5 feet tall and add 5 pounds for every inch over 5 feet.
Example: If you’re 5 feet 3 inches, your appropriate weight is 115 pounds. The ideal range is that weight plus or minus 10 percent, or 104 to 126 pounds.
- If you’re a man, give yourself 106 pounds for being 5 feet tall and add 6 pounds for every inch over 5 feet.
Example: A 5-foot-6-inch male should weigh about 142 pounds. The ideal weight range is then 128 to 156 pounds.
You can also use your BMI to determine whether you’re under- or overweight. The BMI takes into account your height to determine whether your weight is too high. This is only fair. A 5-foot-4-inch woman who weighs 150 pounds is overweight, but a 5-foot-9-inch woman who weighs the same isn’t overweight.
If you’re good at math (or good with a calculator), you can determine your own BMI. Multiply your weight in pounds by 703. Divide the result by your height in inches. Divide that result by your height in inches again. This is your BMI in meters per kilogram squared. (You transfer pounds and inches into kilograms and meters with the 703 fudge factor.)
There are also online BMI calculators:http://www.nhlbi.nih.gov/guidelines/obesity/BMI/bmicalc.htm
By definition, a BMI of 25 to 29.9 is overweight and a BMI of 30 or greater is obese. A BMI of 22 to 25 is normal.
Example: A 150-pound, 5-foot-4-inch (64-inch) woman is overweight with a BMI of 27.5. A 150-pound, 5-foot-9-inch (69-inch) woman has a normal BMI of 22.2. If you prefer the easy way of determining your BMI, use the tables below. The lower table has more detailed BMI chart with weight in lbs & kg and height in ft/inches & cms.
Above: simple BMI chart
Above: more detailed BMI chart with weight in lbs & kg and height in ft/inches & cms.
Determining your daily caloric needs
Caloric needs are different depending on age, sex, and level of activity. For example, if a woman is pregnant or breast-feeding, she obviously needs more kilocalories. But if a person is trying to lose weight, then he needs to reduce the total kilocalories per day. When you know the appropriate weight for your height, you can determine the number of daily kilocalories to either maintain or reduce your present weight. Consider working with a dietitian to make sure you’re getting the right nutrients while staying within your daily caloric limits.
A pound of fat contains 3,500 kilocalories. To lose a pound of fat, therefore, you must eat 3,500 kilocalories less than you need. You can do this a couple of ways:
- By reducing your daily intake 500 kilocalories for seven days
- By doing 200 kilocalories of exercise a day (see article 12 for more about exercise) and reducing the diet by only 300 kilocalories daily.
For most people, a combination of diet and exercise seems to work much better than diet alone.
You don’t have to lose weight all the way down to your appropriate range to benefit from weight loss. A loss of 5 to 10 percent of your current weight brings important benefits in terms of blood pressure, blood fats, and blood glucose (if diabetes is present).
Example: A 5-foot-3-inch woman who weighs 150 pounds should weigh within a range of 104 to 126 pounds, with 115 being her appropriate weight. At 115 pounds, she would require 115 × 10 or 1,150 kilocalories each day plus more, depending on her level of exercise. This calculation is derived from the heights and weights of a population of normal healthy men and women.
If she’s sedentary, she’s entitled to 10 percent more kilocalories, a total of 1,265 kilocalories daily. If she’s moderately active, she gets 20 percent more, a total of 1,380 kilocalories daily. A very active woman may need 40 percent or more extra kilocalories to cover her exercise needs, up to 1,610 kilocalories daily.
By keeping her daily intake to 1,400 while doing 300 kilocalories of exercise daily, she can lose a pound of fat a week.
Adjusting your DASH diet
When you know your daily kilocaloric goal, you can go back to the DASH program and subtract or add servings appropriately. To figure out the DASH program at a lower caloric range without the assistance of a dietitian, Table 5 shows the breakdown of servings for 2,000-, 1,800-, and 1,500- kilocalorie DASH programs.
|Food Group||2,000 Kilocalorie||1,800 Kilocalorie||1,500 Kilocalorie Servings|
|Meats and Fish||2||1 3/4||1 3/4|
|Fats and Oils||2 1/2||2 1/2||1 1/2|
|Nuts and Seeds||1||1||3/4|
|Sweets||5 per week||5 per week||5 per week|
Without a doubt, the simplest way to lose weight successfully — without eating foods you don’t like — is the half-portion plan. Many people (including those who come from a variety of ethnic backgrounds with different food preferences) have been able to lose weight and keep it off using this method. When they eat at home, they cut the portion in half and save the other half for another meal. When they eat out, they share an entrée with their partner. Most restaurants give you much more food than you should eat at one meal. Take advantage of it!
If you’re following the DASH diet, you can significantly reduce calories with some simple substitutions:
- Use fat-free or low-fat condiments
- Reduce the oil or dressing in half
- Drink low-fat milk
- Check labels for added sugar
- Avoid fruits canned in sugary syrup
- Add fruit to plain yogurt
- Snack on carrot sticks, celery sticks, plain popcorn, or rice cakes
- Avoid caloric drinks; stick to water with lemon or lime
Ghrelin: The reason you may have trouble losing weight
Many people have wondered why losing weight seems to get harder the more weight you lose. Interestingly, a good scientific reason lies in ghrelin (the Hindu word for growth), a recently discovered hormone that stimulates growth-hormone secretion from the brain. This hormone is also called the hunger hormone because it travels through the blood from the upper part of the stomach to the brain, where it stimulates the appetite. Scientists have discovered that a person’s ghrelin normally rises just before meals and falls when food is taken. But if a person loses weight by dieting, the levels of ghrelin before meals are much higher, causing greater hunger. A person who undergoes stomach bypass surgery (the upper part of the stomach is excluded from the digestive tract) has little ghrelin. This reduction of the hunger hormone helps to explain the loss of appetite after that surgery.
Trying Other Diets
Sometimes you need a boost to get you going in the right direction towards weight loss and the resulting reduction in blood pressure. Generally doctors don’t insist that their patients follow a balanced nutrition plan all the time as long as they are certain that they’re generally getting the good nutrition they need. You may need a special plan to get you started, and then you can continue on a healthy, balanced program like DASH. For example, one of a doctor's patients eats nothing but rice and water one week a month and then eats balanced meals the rest of the time. He has lost a significant amount of weight, has come off all blood pressure medication, and has a blood pressure anyone would envy. He looks and feels great.
Weight loss is difficult for many reasons. In our experience, most patients do well initially but tend to return to old habits. Still, losing weight and keeping it off is definitely possible. At one time, only 1 out of 20 people who lost weight kept it off. Now the figure is closer to one in five. You should certainly check with a dietitian or your physician for new ideas about weight loss.
How do successful losers do it?
What’s different about the people who have lost weight and kept it off? The National Weight Loss Registry surveyed more than 3,000 people to find out. The registry surveyed people who had lost at least 30 pounds and kept it off for at least one year.
The people had a starting BMI of 36, lost an average of 71 pounds, and currently had an average BMI of 25. Here are some of their characteristics:
- 74 percent had one or both overweight parents.
- 20 percent were overweight by age 18.
- They had recycled (gained and lost) an average of 271 pounds over their lifetime.
- Most had lost weight in the usual ways: restricting foods, portion control, counting kilocalories, and limiting fats.
- Their average kilocalorie intake was 1,300 kilocalories per day for women and 1,650 for men to maintain weight loss.
- Their average weekly kilocalorie expenditure from exercise was 2,800 kilocalories.
- 55 percent used a program such as Weight Watchers, Over-eaters Anonymous, or a dietitian; 45 percent lost weight on their own.
- 77 percent reported a medical or emotional trigger that caused them to lose weight successfully.
If you study these characteristics, you find that these people aren’t following strange plans to lose weight. They’re using ordinary nutritional plans that are usually balanced, in addition to exercise and sometimes outside help.
Successfully losing weight and maintaining it also requires a willingness to exercise. Article 12 is all about exercise both for health and for weight loss. If, for some reason, you can’t move your legs to exercise, you can get a satisfactory workout using your upper body. Most people who are successful at weight loss maintenance describe exercise as a key part of their success.
The following diets aren’t balanced diets and shouldn’t be your nutritional plan for more than several weeks to get you going. Unfortunately, they’re generally associated with regaining the weight if they become your primary program because they’re usually boring, repetitious, and have little to do with the pleasure of eating.
- Very-low-kilocalorie diets: These diets provide 400 to 800 kilocalories a day of protein and carbohydrate with supplemental vitamins and minerals. They’re safe when supervised by a physician and when you need rapid weight loss (like in the case of a heart condition). They result in rapid initial weight loss and less need for high blood pressure medication. In fact, if you continue your medication, you may suffer dizziness.
- Animal-protein diets (such as the Atkins diet): Food is limited to animal protein, vitamins, and minerals in an effort to maintain body protein. Patients often complain of hair loss, and they rapidly regain weight when they discontinue the diet. This is not a balanced diet.
- Fasts: A fast means giving up all food for a period of time and taking only water, vitamins, and minerals. A fast is such a drastic change from normal eating habits that most patients don’t remain on it for very long. As a result, they regain the weight.
Using Outside Help
The dietitian can be a tremendous source of information on all aspects of nutrition. He can help you determine your correct weight and the ideal number of kilocalories per day to reach that weight. Your physician or local hospital can provide the name of a reputable dietitian.
Other programs have also proved to be valuable for some people. Many of these programs provide all the food you care to eat, making it exceedingly easy to follow them (although they can also be exceedingly expensive). These programs emphasize gradual weight loss and a connection to more normal eating habits, both of which seem to be a more successful way to lose weight.
- Jenny Craig: This organization provides the food that you eat, which you must pay for. It offers information on food behavior modification.
- Weight Watchers: This organization emphasizes slow weight loss, exercise, and behavior modification. It charges for weekly attendance at its meetings, which you can find all over the world. Although it doesn’t require you to purchase any products, its brand of food is available for purchase. Weight Watchers has developed a point program that allows you to eat what you want — as long as the total is within your point allowance each day. After you reach your goal, you can belong to the organization for free as long as you stay at that weight or near it. Weight Watchers is very motivating.
Next article: Keeping salt out of your diet
It is possible to follow a diet to lower your blood pressure. This is the DASH diet which is a blood pressure diet.