Pros and Cons of the DASH Diet for High Blood Pressure

02/16/2023 | 9 min. read

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If you have high blood pressure, your doctor may have recommended the DASH diet. Promoted by the American Heart Association, the National Heart, Lung, and Blood Institute (NHLBI), and other organizations, it is one of the most popular diets for controlling blood pressure.

What Is the DASH Diet?

DASH—an acronym for Dietary Approaches to Stop Hypertension—has been shown in clinical trials to lower systolic blood pressure by an average of 6–11 mm Hg. Other proven benefits include reducing the risk of heart attack and stroke, preventing or controlling type 2 diabetes, and helping with weight loss.

Like most high blood pressure diet plans, DASH restricts sodium, but it also emphasizes potassium, magnesium, fiber, and other protective nutrients. Food choices are diverse and adaptable, and although it doesn’t require counting calories or carbs, fats, and proteins, DASH guidelines do include portion sizes and number of servings. (Servings mentioned below are based on a daily intake of 2,000 calories.)

As you will see, there are many things to love about the DASH Diet, but the devil is in the details. Let’s take a look.

Grain Products: Too Many Servings

DASH guidelines: 6–8 servings of grains, preferably whole grains, per day. A serving = 1 slice of bread, 1 ounce of dry cereal, or ½ cup of cooked rice, pasta, or cereal.

Examples: Whole-wheat bread and rolls, whole-wheat pasta, English muffins, pita bread, bagels, cereals, grits, oatmeal, brown rice, unsalted pretzels, popcorn.

  • Pros: The DASH diet recommends whole grains, which are a good source of protein, vitamins, minerals, and complex carbohydrates, which fill you up and provide sustained energy. Many studies reveal the benefits of whole grains for cardiovascular health, weight control, and more.
  • Cons: Six to eight daily servings of grains, even whole-grain products, is wildly excessive. Furthermore, most of the suggested foods are highly processed, and many are made with wheat flour. Even whole-wheat bread has a moderately high glycemic index, meaning it causes spikes in blood sugar. A high glycemic diet can increase insulin resistance, which is closely associated with hypertension.
  • Modifications: One or two servings of minimally processed grains three to four times a week is fine but try to cut back on all refined grains and items made with flour, especially wheat flour. Sensitivity to gluten and other proteins in wheat is a growing, often overlooked concern. Good choices include organic sprouted grain bread, steel-cut oatmeal, and brown rice, barley, quinoa, and other whole grains.

Meat, Poultry, Fish, and Eggs: Quality Over Quantity

DASH guidelines: 6 or fewer servings of meat, poultry, fish, or eggs per day. A serving = 1 ounce of cooked meat, poultry, or fish, or 1 egg. (Keep in mind that an average serving of meat, chicken, or fish is 4 ounces.)

Examples: Lean meats, visible fats trimmed away, skin removed from poultry. Recommended cooking methods: broiling, roasting, poaching.

  • Pros: Including meat and eggs, which are often needlessly vilified because of their saturated fat, is a smart move. On the other hand, recommending lean cuts is also good, since a high saturated fat intake increases inflammation and disease risk. Suggested preparation methods are great—and are even easier these days with air fryers and Instant Pots.
  • Cons: There should also be more emphasis on quality. Most red meat, poultry, eggs, and even fish are a product of factory farming, from animals raised in inhumane conditions, fed GMO corn and soy, and treated with antibiotics.
  • Modifications: Grass-fed beef, pasture-raised chickens/eggs, and wild-caught fish, especially omega-3-rich salmon, are your best choices. As for quantities, I believe you have a little wiggle room. Several healthy food plans such as the Paleo diet include significantly higher amounts of lean protein.

Vegetables and Fruits: More Veggies, Less Fruit

DASH guidelines: 4–5 servings of vegetables and 4–5 servings of fruit per day. A serving = 1 cup raw leafy vegetables, ½ cup chopped raw or cooked vegetable, or ½ cup vegetable juice; 1 medium fruit, ¼ cup dried fruit, ½ cup fresh, frozen, or canned fruit, or ½ cup fruit juice.

Examples: Broccoli, carrots, collards, green beans, green peas, kale, lima beans, potatoes, spinach, squash, sweet potatoes, tomatoes; apples, apricots, bananas, dates, grapes, oranges, grapefruit, grapefruit juice, mangoes, melons, peaches, pineapples, raisins, strawberries, tangerines.

  • Pros: Fruits and vegetables are excellent sources of fiber and nutrients like potassium, which counters some of the effects of sodium and helps lower blood pressure. DASH’s four to five daily servings of vegetables is commendable, as is the inclusion of leafy greens, broccoli, tomatoes, carrots, etc., over starchy, high-glycemic vegetables like white potatoes and corn.
  • Cons: Four to five servings of fruit is too much. Fruits are loaded with beneficial nutrients, but they are also loaded with sugars. Yes, it’s natural sugar, but it is ultimately converted to glucose. Excess fruit is particularly problematic for anyone with diabetes or insulin resistance—conditions that affect many people with hypertension.

  • Modifications: There is no limit on leafy greens, broccoli, tomatoes, etc., but go easy on starchy vegetables like potatoes and corn and on fruit. Two servings of fruit a day is more appropriate, especially for people with blood sugar issues. Note that fruit juice and dried fruit are highly concentrated sources of sugar. Produce shown to help lower blood pressure includes celery, garlic, onions, beet juice, and blueberries. Buy organic whenever possible.

Dairy: Not for Everyone

Dash guidelines: 2–3 servings per day of fat-free or low-fat dairy products. A serving = 1 cup milk or yogurt, or 1½ ounce cheese.

Examples: Fat-free milk or buttermilk, fat-free, low-fat, or reduced-fat cheese, fat-free/low-fat regular or frozen yogurt.

  • Pros: Milk contains protein, calcium, and vitamins A, D, K, and B12. Some studies have linked dairy consumption with a reduction in blood pressure.
  • Cons: Many experts believe that more research is needed to support the inclusion of dairy in a heart-healthy diet. Moreover, the focus on reduced-fat dairy may not be warranted. A recent study found that full-fat dairy had the same effects on blood pressure and lipid levels as low-fat products. And what’s with the inclusion of frozen yogurt? It’s a dessert!
  • Modifications: Dairy isn’t essential for cardiovascular health, so there’s no need to include it if you are lactose intolerant. If you do eat dairy foods, two servings a day is adequate. Opt for organic products from grass-fed cows, which contain higher levels of omega-3s, and don’t get hung up on reduced-fat dairy.

Fats and Oils: Avoid Most Vegetable Oils

DASH guidelines: 2–3 servings of fats and oils daily. A serving = 1 teaspoon soft margarine or vegetable oil, 1 tablespoon mayonnaise, or 2 tablespoons salad dressing.

Examples: Soft margarine, vegetable oil (canola, corn, olive, safflower), low-fat mayonnaise, light salad dressing.

  • Pros: Unlike some super-low-fat diets, DASH acknowledges the essential role of fat in a healthy diet.
  • Cons: The examples provided are a big red flag. Olive oil, a minimally processed monounsaturated fat abundant in protective polyphenols, is the only one I wouldn’t kick to the curb. Canola, corn, sunflower, other vegetable oils, and margarines are highly processed, unstable, and pro-inflammatory.
  • Modifications: Make olive oil your go-to. In addition to curbing inflammation, diets rich in olive oil are associated with lower blood pressure and better heart health. Avocado oil is also recommended and, for sauteing and heating, organic coconut oil because it doesn’t break down under heat. Despite coconut oil’s reputation as an “evil” saturated tropical oil, it is mainly composed of medium-chain triglycerides, which have positive effects on arterial health.

Nuts, Seeds, and Dried Beans and Peas: Go Nuts!

DASH Guidelines: 4–5 servings of nuts, seeds, or dried beans and peas per week. A serving = ⅓ cup or 1½ ounce nuts, 2 tablespoons peanut butter, 2 tablespoons or ½ ounce seeds, ½ cup cooked legumes (dried beans, peas).

Examples: Almonds, filberts, mixed nuts, peanuts, walnuts, sunflower seeds, peanut butter; kidney beans, lentils, split peas.

  • Pros: Nuts, seeds, and beans contain protein plus phytosterols, which have demonstrated benefits for cardiovascular health. Beans also have a lot of fiber, and nuts and seeds are rich in healthy fats.
  • Cons: Considering the many benefits of these foods, I feel that four to five servings a week—less than one a day—isn’t enough. In fact, a long-term study found that people who ate more than three servings of nuts per week had a 39% lower risk of death.
  • Modifications: A serving or two of legumes and nuts every day is a more reasonable recommendation. Don’t forget to include flaxseed. Studies reveal that daily consumption of flaxseed significantly lowered blood pressure in study participants with hypertension.

Sweets and Added Sugars: Just Say No!

DASH Guidelines: 5 or fewer servings of sweets and added sugars per week. A serving = 1 tablespoon sugar, jelly, or jam, ½ cup sorbet or gelatin dessert, 1 cup lemonade.

Examples: Fruit-flavored gelatin, fruit punch, hard candy, jelly, maple syrup, sorbet and ices, sugar.

  • Pros: Cutting way back on all sources of sugar is an essential guideline. A high intake of sugars raises blood sugar and insulin resistance, promotes inflammation, contributes to weight gain, and increases risk of hypertension and other chronic diseases.
  • Cons: No disagreement here on the importance of minimizing sugars and sweets.
  • Modifications: My only comment is that the examples of sweets aren’t the most inspiring. If you’re going to indulge your sweet tooth, make it worth your while with a couple of squares of dark chocolate, fresh berries with sweetened whipped cream, or a small serving of a homemade dessert. Also look into healthy (not artificial) sweeteners like stevia and monk fruit.

Salt and Sodium: Is DASH Limit Too Low?

DASH Guidelines: 1,500–2,300 mg of sodium per day. 1 teaspoon of sodium chloride (table salt) = 2,300 mg of sodium.

Examples: Most of the sodium we eat is in processed and prepared foods; read labels carefully and choose foods with less sodium.

  • Pros: The emphasis on processed and restaurant foods as opposed to just ditching the saltshaker is good advice.
  • Cons: Limiting sodium intake to 2,300 mg and especially to 1,500 mg is challenging. Salt sensitivity varies, and many studies have shown little effect of sodium consumption on blood pressure. Although excessive salt intake isn’t recommended, not everyone requires such draconian sodium restriction.

  • Modifications: A reasonable sodium intake for healthy blood pressure, according to my dad cardiologist Steve Sinatra, is 2,800 mg per day. Eating more potassium-rich foods or using a salt substitute that contains potassium, which balances sodium, is also helpful.

Bottom Line

The U.S. News & World Report’s 2023 ranking of dozens of diets gave DASH top billing in heart-healthy diets. DASH also ran a close second to the Mediterranean diet—a long-time favorite of mine—for best diet overall.

The DASH diet has a lot going for it. It is versatile, accommodates a wide range of food preferences, and supported by free downloadable menus, recipes, and tips for staying on track.

Bottom line, the DASH diet is pretty good—and with the modifications we have discussed, it can be great!

Dr. Drew Sinatra

Meet Dr. Drew Sinatra

Dr. Drew Sinatra is a board-certified naturopathic doctor and self-described “health detective” with a passion for promoting natural healing, wellness, and improving quality of life by addressing the root cause of illness in patients of all ages. His vibrant practice focuses on treating the whole person (mind, body, and spirit) and finding missed connections between symptoms and health issues that are often overlooked by conventional medicine.

More About Dr. Drew Sinatra