In a feeding trial, the DASH diet lowered the top number about 11 points and the bottom about 5.5 in people with high blood pressure, with the drop showing up in the first 2 weeks; adding less salt took the top number down about 11.5.
Ask a waiting room for the best diet for high blood pressure and you'll hear about keto, fasting and juice cleanses. The best-studied eating plan for high blood pressure is DASH, short for Dietary Approaches to Stop Hypertension. It promises nothing dramatic, and it's the one the 2025 American Heart Association guideline names when it recommends heart-healthy eating (guideline).
DASH asks for no special foods. It's mostly a change in proportions, with more vegetables, fruit, beans and low-fat dairy and less of the salty, packaged food most of us eat by default.
The book's grade: SUPPORTED (works). The DASH eating pattern is a Start here item, and DASH with less salt is graded SUPPORTED too. Both sit at the top of the book's ranking for blood pressure.
What is the DASH diet?
At about 2,000 calories a day, the government's DASH plan works out to these daily servings (NHLBI):
- Grains: 6 to 8 servings, mostly whole grains.
- Vegetables: 4 to 5 servings.
- Fruit: 4 to 5 servings.
- Low-fat milk or yogurt: 2 to 3 servings.
- Meat, poultry and fish: 6 ounces (cooked) or less.
Nuts, seeds and beans come 4 to 5 times a week, and sweets 5 times a week or fewer. Sodium stays under 2,300 mg a day, and 1,500 mg lowers blood pressure further (NHLBI).
The DASH food list and serving sizes
The servings are smaller than most people guess. These come from the DASH worksheets of the National Heart, Lung, and Blood Institute (NHLBI):
- Grains: 1 slice of bread, or ½ cup of cooked rice, pasta or cereal.
- Vegetables: 1 cup of raw leafy greens, or ½ cup of cut-up raw or cooked vegetables.
- Fruit: 1 medium piece, or ½ cup of fresh, frozen or canned fruit.
- Milk and yogurt: 1 cup. Lactose-free milk, fortified soy milk and kefir count too.
- Meat, poultry and fish: 1 ounce cooked, or 1 egg.
- Nuts and beans: a third of a cup of nuts, or ½ cup of cooked beans or lentils.
If you eat less than 2,000 calories a day, scale the servings down.
If you'd rather not count, use a plate. Fill half with vegetables and fruit, a quarter with whole grains and a quarter with protein, with beans or lentils often, plus a glass of milk or a cup of yogurt on the side. The plate is a shortcut to DASH. Nobody has tested the picture on its own, so the evidence behind it comes from the DASH trials. Rice, tortillas, roti and cornbread all fit.
How much does the DASH diet lower high blood pressure?
The first DASH trial fed 459 adults, none on blood pressure pills, every meal for 8 weeks. Salt and weight were held steady, so any change came from the food (DASH trial). On office readings:
- People with high blood pressure: the top number fell about 11 points more than on a typical American diet, and the bottom number about 5.5 more.
- People without high blood pressure: about 3.5 on top and 2 on the bottom.
For example, someone at 146/92 could land around 135/87, though your own result could differ. The change showed up within the first 2 weeks (trial).
Adding less salt did more. In the DASH-Sodium trial, DASH with low salt lowered the top number about 11.5 points in people with high blood pressure, compared with a typical diet with high salt (DASH-Sodium). The higher people started, the bigger the drop (trial):
- Starting top number under 130: about 5.3 points.
- 130 to 139: about 7.5.
- 140 to 149: about 9.7.
- 150 or higher: about 21, in a small group.
It works on top of pills. In GoFreshRx, 176 Black adults already being treated for high blood pressure got 12 weeks of DASH groceries delivered, plus a dietitian's help. Their top number fell about 5 points more than in a group given cash instead (GoFreshRx). If your readings fall on DASH while you take pills, your doctor may need to lower a dose. Watch for dizziness when you stand, and never stop or change a pill on your own.
How DASH holds up in everyday life
In a feeding study, someone else shops and cooks. Once you count every kind of DASH trial, the average drop is smaller, about 3 points on the top number in a review of 30 trials (review).
Help makes a difference. In the PREMIER trial of adults not on blood pressure pills, 38% had high blood pressure at the start. After 6 months, that share was 26% with brief advice and 12% with months of coaching plus DASH (PREMIER).
Weight loss adds even more. In the ENCORE trial, overweight adults with untreated high blood pressure spent 4 months on DASH alone, DASH plus weight loss and exercise, or their usual diet. With the full package, the top number fell about 16 points and the bottom about 10. DASH alone gave about 11 and 7.5, and the usual diet about 3 and 4 (ENCORE).
A one-day DASH diet meal plan
- Breakfast: rolled oats cooked in low-fat milk, with a sliced banana and a few unsalted walnuts.
- Lunch: a big salad with rinsed canned chickpeas, leftover chicken and an oil-and-vinegar dressing, plus an orange.
- Afternoon snack: an apple or a few carrot sticks.
- Evening snack: unflavored yogurt with frozen berries.
- Dinner: frozen stir-fry vegetables with chicken, a teaspoon of reduced-sodium soy sauce and brown rice.
It has no deli meat, canned soup or salty snack. Using USDA's standard values for these foods, I estimate it at roughly 900 mg of sodium, before any salt you add at the stove or table (USDA).
Try it at home (if you have a cuff): Average a week of home readings, two each morning and evening. Then eat DASH-style for two weeks, with half your plate vegetables and fruit at lunch and dinner, milk or yogurt twice a day, and one salty packaged food swapped for a fresh one. In the second week, take another week of readings at the same times and compare the averages. If you take blood pressure pills, tell your doctor before you start.
DASH vs other diets for blood pressure
The guideline says the other eating patterns it reviewed lowered blood pressure less than DASH did (guideline).
- Mediterranean: about 1.5 points in 35 trials (review). PLAUSIBLE (might help), and a fine alternative if DASH doesn't suit you.
- Keto: less than 1 point in 23 trials, small enough to be chance (review). UNLIKELY TO HELP.
In a review of 121 trials of named diets in overweight adults, the differences between diets were "generally trivial to small," and the authors said people can choose the one they prefer (review). Pick the pattern you'll still be eating next year, one your family can share and that keeps the foods you grew up with.
Who should check with a doctor before starting DASH
- Kidney disease or a pill that holds on to potassium (ACE inhibitors, ARBs, spironolactone). DASH is high in potassium and phosphorus, so ask your doctor or dietitian how to adapt it, guided by your blood tests. Many people with early kidney disease and normal potassium can eat this way, and a lower-potassium DASH-style plan has been tested (DASH4D).
- Blood pressure pills, a water pill, insulin or other diabetes medicines. Your pressure or blood sugar can fall faster than your doses are set for, especially if you also cut salt or lose weight. Ask before you start, and never change a dose on your own.
- Heart failure. Your cardiologist sets your sodium target.
Bottom line
DASH is the best-tested way to eat for high blood pressure. In a feeding trial it lowered the top number about 11 points in people with high blood pressure, and with less salt about 11.5. In everyday life the average drop is smaller, about 3 points, but coaching, delivered groceries and weight loss make it bigger. It adds to blood pressure pills, so tell your doctor before you start if you take them.
Questions people ask
What foods are on the DASH diet?
Vegetables, fruit, whole grains, beans, lentils, nuts, low-fat milk and yogurt, with modest amounts of fish, poultry and lean meat. It keeps sweets and salty packaged food low, and sodium under 2,300 mg a day.
How fast does the DASH diet lower blood pressure?
In the first DASH feeding trial, the drop showed up within the first 2 weeks. Give it about a month and compare weekly home averages before you judge it.
How do I start the DASH diet?
Start where you have the most room, whether that's the fast-food lunch or the chips after dinner, and add DASH foods to meals you already like. If your clinic or insurance offers a dietitian or a cooking class, take it. Check your weekly home average after a month.
Is the DASH diet the same as a low-sodium diet?
They're separate steps that work best together. In the DASH-Sodium trial, DASH helped at every salt level, cutting salt helped on both diets, and doing both gave the biggest drop.
Is the DASH diet good for weight loss?
DASH isn't built as a weight-loss diet. In the ENCORE trial, weight barely moved on DASH alone. People who added a weight-loss and exercise program lost about 19 pounds, and their top number fell about 16 points in 4 months.
Where DASH sits in the full ranking
DASH is one line on the scoreboard in Your Blood Pressure by the Numbers, coming soon. The book also grades the potassium-enriched salt substitute (SUPPORTED, with a medicine check first), milk and yogurt (PLAUSIBLE, might help) and pink or sea salt (UNLIKELY TO HELP), each with its own number. In the meantime, read how to lower blood pressure naturally for the top of the list, or salt substitutes and blood pressure.