How much does DASH actually lower blood pressure?

5.5 mmHg on the top number and 3.0 on the bottom, against a typical American diet, in a study where all food was provided, salt was fixed and body weight was held steady. In people who had high blood pressure it was 11.4 and 5.5 mmHg. Combined with cutting salt, it reached 11.5 mmHg on the top number in people with high blood pressure. These are among the most reliable numbers on this site, because the design removed almost everything else.

Does it prevent heart attacks and strokes?

Nobody knows, and this is the honest gap. A 2025 Cochrane review of every trial found five, with 1,397 people, and follow-up no longer than 18 months. Where heart attacks and strokes were checked, there were none in either group. Long-running studies that watched people link a high DASH score with 24 percent less heart disease and 18 percent fewer strokes. But those studies only watch people, and a questionnaire score is not the diet that was fed.

Will I lose weight on it?

Not from the diet itself. The studies behind the blood pressure result held body weight steady on purpose, because that was the point. When a weight loss program was added in a study where people ate on their own, blood pressure fell further and blood vessel measures improved more. So the weight loss was doing its own work, not the diet.

Is there anything in it that moves the wrong way?

HDL (good cholesterol) fell 3.7 mg/dL against control at steady weight, most in people who started highest. The study's own authors wrote that this could work against the heart benefit and needed more study. It has had little since. There was also no real effect on triglycerides at steady weight.

Do I need to cut sodium as well?

They were tested separately, and both worked. In the study that tested both, the diet lowered blood pressure at every salt level, and cutting salt lowered it on both diets, with the biggest effect from doing both. The two overlap rather than simply adding up. The diet's own edge was bigger at high salt than at low. And in the 2025 diabetes feeding study, the authors reported that the salt effect looked stronger than the diet effect.

Whole-food12 studies in people cited

DASH

Written by Aaron CuhaReviewed Sep 2026

Also called: Dietary Approaches to Stop Hypertension, DASH eating plan

The blood pressure drop is real. It was measured with all food provided and body weight held steady, and it is the cleanest result in this section. Data on real heart attacks and strokes barely exists: a 2025 Cochrane review found five trials, and no strokes or heart attacks in them.

What it actually is

A way of eating defined by food groups, not by a carb, fat or protein target. It is high in fruit, vegetables, low fat dairy, whole grains, nuts, beans and lentils. It cuts back on saturated fat, total fat, cholesterol, red meat, sweets and sugary drinks. It came out of a feeding study, not a book, and the way that study was run is why people quote it with confidence. People were given their food, salt intake was fixed, and body weight was held steady. So the result comes from what was in the food and nothing else.

How its fans say it works

Not one lever but a mix, and its designers said so openly. Potassium, calcium, magnesium and fibre from fruit, vegetables and low fat dairy had each been linked to lower blood pressure in earlier work. The idea was that putting them together in one way of eating would do more than any single supplement had. Less saturated fat and cholesterol were added to improve cholesterol levels. Because it was built as a package, no study has pinned down which part lowers blood pressure. The study group that dropped the dairy and the fat cuts, and kept only the fruit and vegetables, got about half the result.

What happened when calories were controlled

Best kind of study available: calories matched

Both groups ate the same number of calories, so a difference comes from what was in the diet, not how much people ate.

This is the rare diet whose main evidence comes from feeding studies with calories controlled. Food was provided, salt was fixed, and body weight was held steady on purpose, in the first study and in every major one after it. So the blood pressure and cholesterol results are not weight loss results. The top blood pressure number fell 5.5 mmHg against a typical American diet, and 11.4 mmHg in people who had high blood pressure.

Appel 1997: 459 adults ate a standard control diet for three weeks, then spent eight weeks on one of three diets: that same control diet, a fruit and vegetable diet, or the mix now called DASH. Salt intake and body weight were kept steady. DASH lowered the top blood pressure number 5.5 mmHg and the bottom number 3.0 mmHg more than the control diet, both clear results. The fruit and vegetable diet lowered the top number 2.8 mmHg, a clear result, and the bottom number 1.1 mmHg, too small to be sure. So roughly half the effect came from fruit and vegetables alone.
The same study split people by whether they started with high blood pressure, and this is the number that matters most. In the 133 people with high blood pressure, DASH lowered it 11.4 and 5.5 mmHg more than the control diet. In the 326 without it, the drop was 3.5 and 2.1 mmHg. The diet does more for people who need it more.
Obarzanek 2001 measured cholesterol in 436 of those people while their weight stayed steady. Against the control diet, DASH lowered total cholesterol 13.7 mg/dL and LDL (bad cholesterol) 10.7 mg/dL. It also lowered HDL (good cholesterol) 3.7 mg/dL. All three were clear results, and there was no real change in triglycerides. The HDL drop is in the paper and is rarely repeated. The authors wrote that it could work against the heart benefit and needs more study. Men's LDL fell 11.2 mg/dL more than women's.
Sacks 2001, the DASH-Sodium study: 412 people ate either DASH or a control diet, each at high, medium and low salt for 30 days at a time. DASH at low salt, compared with the control diet at high salt, left the top number 7.1 mmHg lower in people without high blood pressure and 11.5 mmHg lower in those with it. Salt and diet stacked. But the diet's own edge was bigger at high salt than at low, so the two partly overlap rather than simply adding up.
Juraschek 2017 looked again at DASH-Sodium, split by starting blood pressure. Low salt DASH against high salt control lowered the top number by 5.3, 7.5, 9.7 and 20.8 mmHg in people starting under 130, at 130 to 139, at 140 to 149, and at 150 or above. The salt effect clearly grew with starting blood pressure. The diet effect did not. The 20.8 mmHg figure comes from the smallest group, and the authors call for study above 160 mmHg, which nobody has done.
DASH4D, 2025, is the newest feeding study, and it narrows the claim. 102 adults with type 2 diabetes and a top number of 120 to 159 mmHg each ate four diets for five weeks, one after the other. All food was provided, no outside food was allowed, and weight was held steady. A DASH-style diet adjusted for diabetes, with less salt, beat a typical US diet with more salt by 4.6 mmHg on the top number and 2.3 mmHg on the bottom. The likely range for the top number ran from 2.0 to 7.2 mmHg. Most of the drop came in the first three weeks, and the authors report that the salt effect looked stronger than the diet effect. 66 percent of people were already on two or more blood pressure drugs.

What happened when people just ate it

Results when people ate on their own are good, but they are not the feeding study results, and one study is worth knowing before you start. PREMIER put 810 adults with higher than ideal blood pressure into three groups. One got advice only. One got an established lifestyle program covering weight loss, cutting salt, exercise and alcohol. One got that same program plus DASH coaching. At six months the top number had fallen 3.7 mmHg more on the established program than on advice alone, and 4.3 mmHg more on the program plus DASH. The gap between those two groups was 0.6 mmHg, too small to be real. Adding DASH coaching on top of an already intensive lifestyle program added almost nothing to blood pressure. The share of people who still had high blood pressure was lowest in the DASH group, at 12 percent against 17 and 26 percent, but against the established program that gap was also too small to be sure. ENCORE points the other way and asked a different question. 144 adults who were overweight or obese, with high blood pressure, ate on their own for four months. Blood pressure at the clinic fell 16.1 over 9.9 mmHg on DASH plus a weight loss program, 11.2 over 7.5 on DASH alone, and 3.4 over 3.8 on their usual diet, a clear result. Artery stiffness, the body's blood pressure reflex and the size of the heart's main pumping chamber all improved more when weight loss was added. Azadbakht 2005 prescribed a lower calorie DASH diet to people with metabolic syndrome for six months and reported very large changes. They included a top-number drop of 11 mmHg, and weight losses reported as 15 to 16 kg against the control group. Weight losses that big in a six-month study of people eating on their own are far beyond what other studies in this section produced. So its blood pressure and cholesterol results should be read as a package with an unusually large weight change, not as a diet effect at steady weight.

Protein, and whether it muddies the result

DASH sets no protein target, and none of its studies matched or reported protein between groups. What it does do is change where protein comes from: more low fat dairy, beans, nuts, fish and poultry, and less red and processed meat. No DASH study has measured muscle. The feeding studies were built to keep body weight steady, so there is no body make-up data here at all. Anyone pairing this diet with a weight loss drug or weight training gets no protein guidance from it and will have to add that separately.

The measured intakes behind the protein figures are on the protein page.

What reliably moves

Measure	Direction	From
Blood pressure (top number)	Down, and this is the result the diet exists for	5.5 mmHg against a control diet at steady weight and fixed salt, and 11.4 mmHg in people who had high blood pressure. Combined with cutting salt, 7.1 mmHg in people without high blood pressure and 11.5 mmHg in people with it. In adults with type 2 diabetes already on medicine, 4.6 mmHg.
LDL (bad) cholesterol	Down	10.7 mg/dL against control with body weight held steady, a clear result. The drop was larger in men than women by 11.2 mg/dL.
HDL (good) cholesterol	Down, and this is the result fans leave out	3.7 mg/dL lower against control, a clear result, and it fell most in people who started highest. The study's own authors flagged that it could work against the heart benefit and needed more study. It has not had much.
Triglycerides (blood fats)	No real effect	In the controlled feeding study, with weight steady, there was no real effect on triglycerides. Studies where people ate on their own and also lost weight report drops, which is a different result from a different kind of study.
Uric acid in the blood	Down	0.35 mg/dL against control at steady weight, a clear result, and 1.29 mg/dL in the eight people who started at 7 mg/dL or above. The same study found that eating more salt lowered uric acid, the opposite of what most people assume.
Troponin I and CRP (blood markers of heart strain and inflammation)	Down	DASH against control lowered troponin I 18 percent and CRP 13 percent, with no change in NT-proBNP, another heart strain marker. Cutting salt did the reverse: NT-proBNP down 19 percent, troponin unchanged, and CRP slightly up, 9 percent. These are early warning markers, not heart attacks or strokes.
Heart attack, stroke, death	Not measured	A 2025 Cochrane review of every trial found five, with 1,397 people. Where these events were reported at all, there were none in either group. Follow-up ran 16 weeks to 18 months, and every trial was in people without prior heart disease. This is the gap in this diet.

Long term, and serious health events

The blood pressure evidence is strong but short, and evidence on real heart outcomes barely exists. A 2025 Cochrane review searched up to May 2024 and found five trials with 1,397 people in total. The diets lasted 16 weeks to 12 months, and follow-up ran 16 weeks to 18 months. One trial of 144 people reported no heart attacks and no strokes in either group over a year. Another reported no deaths in 90 people over six months. Against minimal advice, the risk figure for heart attack was 2.99, with a likely range from 0.12 to 73.04. That is a way of saying nothing was really measured. No trial looked at heart failure or artery-opening procedures, and none looked at people who already had heart disease. The review's verdict is that the effect on major heart outcomes is still unclear for lack of solid long-term evidence, and its confidence in that was low to very low. The long-term signal comes from studies that only watch people. Fung 2008 followed 88,517 female nurses for 24 years, checking their diet seven times. Split into five groups by DASH score, from lowest to highest, their risk of heart disease was 1.0, 0.99, 0.86, 0.87 and 0.76, a clear trend. The risk of stroke in the top group was 0.82, also a clear trend. But this study only watched people. Those who score high on a DASH scale differ from those who score low in many ways, and a score from a questionnaire is not the diet that was fed in the hospital unit. Both halves belong in an honest account. The evidence on how it works is about as good as nutrition gets. The evidence on real outcomes is not there yet.

Sources

Study in people1997
A clinical trial of the effects of dietary patterns on blood pressure. DASH Collaborative Research Group.
New England Journal of Medicine
459 adults ate food given to them for eight weeks, with salt and body weight held steady. The combination DASH diet lowered blood pressure 5.5 points on the top number and 3.0 on the bottom, more than the control diet. The drop was 11.4 and 5.5 in the 133 people with high blood pressure, and 3.5 and 2.1 in the 326 without. A diet with only more fruit and vegetables got about half the effect.
459 adults, eight weeks, food provided, sodium and body weight held constant. Combination diet lowered blood pressure 5.5 and 3.0 mmHg more than control (p < 0.001 each), 11.4 and 5.5 mmHg more in the 133 with hypertension, 3.5 and 2.1 mmHg in the 326 without. A fruit and vegetable arm without the dairy and fat changes got about half the effect.
Study in people2001
Effects on blood pressure of reduced dietary sodium and the Dietary Approaches to Stop Hypertension (DASH) diet. DASH-Sodium Collaborative Research Group.
New England Journal of Medicine
412 people ate three salt levels, 30 days each, on either DASH or a control diet. DASH with low salt beat the control diet with high salt by 7.1 points on the top blood pressure number in people without high blood pressure, and by 11.5 in people with it. The diet helped more when salt was high than when it was low.
412 participants, three sodium levels for 30 days each within the assigned diet. DASH at low sodium against control at high sodium: systolic 7.1 mmHg lower without hypertension and 11.5 mmHg lower with it. The diet's advantage was larger at high sodium than at low.
Study in people2001
Effects on blood lipids of a blood pressure-lowering diet: the Dietary Approaches to Stop Hypertension (DASH) Trial.
American Journal of Clinical Nutrition
436 people ate DASH or a control diet while keeping their weight steady. DASH lowered total cholesterol by 13.7, LDL (bad) cholesterol by 10.7, and HDL (good) cholesterol by 3.7, with no clear change in triglycerides. The HDL drop was biggest in people who started with the highest HDL, and the authors said this needs more study.
436 participants, weight stable. Against control: total cholesterol 13.7 mg/dL lower, LDL 10.7 lower, HDL 3.7 lower, all p < 0.0001, no significant triglyceride effect. The HDL reduction was largest in those with the highest baseline HDL and the authors flagged it as needing further study.
Study in people2017
Effects of Sodium Reduction and the DASH Diet in Relation to Baseline Blood Pressure.
Journal of the American College of Cardiology
This looked again at the DASH salt study, split by starting blood pressure. DASH with low salt beat the high salt control diet by 5.3, 7.5, 9.7 and 20.8 points on the top number, going from people under 130 up to those at 150 or above. The effect grew with starting pressure for cutting salt, but not for the diet itself.
Re-analysis of DASH-Sodium by baseline systolic pressure. Low sodium DASH against high sodium control gave differences of 5.3, 7.5, 9.7 and 20.8 mmHg across strata under 130 up to 150 or above. Sodium showed a significant trend across strata (p = 0.004), the diet did not (p = 0.66).
Study in people2021
Effects of Diet and Sodium Reduction on Cardiac Injury, Strain, and Inflammation: The DASH-Sodium Trial.
Journal of the American College of Cardiology
DASH lowered troponin, a heart damage marker, by 18 percent and CRP, an inflammation marker, by 13 percent, but not NT-proBNP, a heart strain marker. Cutting salt lowered NT-proBNP by 19 percent whatever the diet, left troponin alone, and raised CRP a little, by 9 percent. These are blood markers, not heart attacks or strokes.
DASH against control lowered high-sensitivity troponin I 18 percent and CRP 13 percent but not NT-proBNP. Sodium reduction lowered NT-proBNP 19 percent independently of diet, left troponin unchanged and mildly raised CRP 9 percent. Subclinical biomarkers, not events.
Study in people2016
Effects of the Dietary Approaches to Stop Hypertension (DASH) Diet and Sodium Intake on Serum Uric Acid.
Arthritis and Rheumatology
103 adults ate food given to them, with body weight held steady. DASH lowered uric acid in the blood by 0.35, and by 1.29 in the eight people who started at 7 or higher. Eating more salt lowered uric acid, the opposite of what most people assume.
103 adults, feeding trial, body weight constant. DASH lowered serum urate 0.35 mg/dL (95% CI 0.65 to 0.05, p = 0.02) and 1.29 mg/dL in the eight participants with baseline urate of 7 mg/dL or more. Higher sodium intake lowered urate, the opposite of the common assumption.
Study in people2025
Dietary Patterns, Sodium Reduction, and Blood Pressure in Type 2 Diabetes: The DASH4D Randomized Clinical Trial.
JAMA Internal Medicine
102 adults with type 2 diabetes ate four diets for five weeks each, with all food provided and weight held steady. DASH4D with less salt beat a typical US diet with more salt by 4.6 points on the top blood pressure number and 2.3 on the bottom. Most of the drop came in the first three weeks, and cutting salt seemed to matter more than the diet itself.
102 adults with type 2 diabetes, four five-week feeding periods in crossover, all food provided, weight constant. DASH4D with lower sodium beat a typical US diet with higher sodium by 4.6 mmHg systolic (p < 0.001) and 2.3 mmHg diastolic. Most of the effect landed in the first three weeks and the sodium effect appeared stronger than the diet effect.
Study in people2003
Effects of comprehensive lifestyle modification on blood pressure control: main results of the PREMIER clinical trial.
JAMA
810 adults living their normal lives were followed for six months. An established lifestyle program lowered the top blood pressure number by 3.7, and the same program plus DASH advice lowered it by 4.3. That 0.6 gap was too small to rule out chance. Adding DASH on top of strong lifestyle advice added almost nothing.
810 adults, six months, free living. Net systolic reduction 3.7 mmHg for an established lifestyle programme and 4.3 mmHg for that programme plus DASH counselling. The difference between them was 0.6 mmHg, p = 0.43. Adding DASH on top of intensive lifestyle advice added essentially nothing to blood pressure.
Study in people2006
Effects of comprehensive lifestyle modification on diet, weight, physical fitness, and blood pressure control: 18-month results of a randomized trial.
Annals of Internal Medicine
This is the 18-month follow-up of the PREMIER study above, listed for its longer look at the same groups. The six-month report above has the head to head numbers.
The 18-month continuation of PREMIER. Cited here for the longer follow-up of the same randomised comparison; the six-month result above is the one with the head to head numbers.
Study in people2010
Effects of the DASH diet alone and in combination with exercise and weight loss on blood pressure and cardiovascular biomarkers in men and women with high blood pressure: the ENCORE study.
Archives of Internal Medicine
144 adults with overweight or obesity and high blood pressure were followed for four months, living their normal lives. Blood pressure fell 16.1/9.9 on DASH plus weight loss, 11.2/7.5 on DASH alone and 3.4/3.8 on their usual diet, a clear gap. Artery stiffness, blood pressure control and heart muscle size improved more only when weight loss was added.
144 overweight or obese adults, four months, free living. Clinic blood pressure fell 16.1/9.9 mmHg on DASH plus weight management, 11.2/7.5 on DASH alone and 3.4/3.8 on usual diet, p < 0.001. Pulse wave velocity, baroreflex sensitivity and left ventricular mass improved more only when weight loss was added.
Study in people2005
Beneficial effects of a Dietary Approaches to Stop Hypertension eating plan on features of the metabolic syndrome.
Diabetes Care
116 adults with metabolic syndrome followed one of three diets for six months. Compared with the control diet, DASH lowered the top blood pressure number by 11 and triglycerides by 17 to 18, with 15 to 16 kg of weight lost. Weight losses that big in six months are far outside the rest of this research, so the other results come with an unusually large weight change.
116 adults with metabolic syndrome, six months, three prescribed diets. Net reductions against control on DASH of 11 mmHg systolic, 17 to 18 mg/dL triglycerides and 15 to 16 kg of weight. Weight losses that large in a six-month free-living trial are far outside the rest of this evidence base, so the other results travel with an unusually large weight change.
Study in people2008
Adherence to a DASH-style diet and risk of coronary heart disease and stroke in women.
Archives of Internal Medicine
This followed 88,517 female nurses for 24 years and asked about their diet seven times. The women who ate most like DASH had less heart disease and fewer strokes. It tracked what people said they ate, and a questionnaire score is not the same as eating the diet.
88,517 female nurses, 24 years, diet assessed seven times. Coronary heart disease relative risks across DASH score quintiles 1.0, 0.99, 0.86, 0.87, 0.76 (95% CI 0.67 to 0.85, p < 0.001 for trend); stroke 0.82 at the top quintile (p = 0.002 for trend). Observational, and a questionnaire score is not the fed diet.
Review of studies2025
Dietary Approaches to Stop Hypertension (DASH) for the primary and secondary prevention of cardiovascular diseases.
Cochrane Database of Systematic Reviews
A review pooled five studies with 1,397 people who did not have heart disease, followed for 16 weeks to 18 months. No heart attacks or strokes were reported in either group, and there was no data on heart failure. The evidence was weak, so the effect on heart attacks and strokes is unknown.
Five randomised trials, 1,397 participants, follow-up 16 weeks to 18 months, all primary prevention. No myocardial infarctions and no strokes reported in either group where those outcomes were assessed. No data on heart failure or revascularisation. Certainty low to very low and the effect on major cardiovascular outcomes is inconclusive.

What people report

These are things people say about their own eating. Nobody checked them, so they are not evidence. They are here because they tell you what to expect and what to watch for, which the studies do not. They cannot tell you whether anything works.

Blood pressure readings falling within the first two to three weeks. This is reported very often, and it matches the feeding study data closely enough that it is the one community claim the studies directly back.
No change at all, reported by people who already ate close to this way. That fits the study design, where the comparison was a typical American diet and the gap being closed was large.
Disappointment at not losing weight. That is exactly what the first studies predict, because they were built to prevent weight loss.
Trouble fitting in the dairy servings, especially for people who are lactose intolerant or avoid dairy for other reasons.
Hunger and the amount of food both described as high rather than low, since the diet adds food groups more than it removes them.
The cost of all the fruit, vegetables and dairy, and the time to prepare them, the most common practical complaint.
Confusion about whether cutting salt is part of it. In the first study salt was held steady and the diet still worked. In the follow-up study the two were tested separately, and both worked.

Sources: General blood pressure and heart patient communities, write-ups from dietitians, and how well people stuck to the diet in the studies, which is unusually strong because people were given their food. Otherwise unchecked self-report, useful for what to expect and nothing else.

Who this is wrong for

Anyone with advanced chronic kidney disease or a tendency to high blood potassium. Also anyone on a potassium-sparing water pill, an ACE inhibitor or an angiotensin receptor blocker (common blood pressure drugs) who is not having potassium checked. The diet is high in potassium on purpose, and the 2025 diabetes version was made with less potassium than the original for that reason.
Anyone on blood pressure medicine who is not in touch with a prescriber. The effect is fast, with most of it arriving within three weeks in the feeding studies, and it stacks on top of drug treatment rather than replacing it.
Anyone who cannot or will not eat dairy and has no plan to replace the calcium. Low fat dairy is a core part, and the group in the first study that ate the fruit and vegetables without it got about half the blood pressure effect.
Anyone starting it for weight loss. The feeding studies held body weight steady by design. The studies where people lost weight did it by adding a weight loss program, and that addition is what produced the extra blood pressure drop in ENCORE.
Anyone who wants lower triglycerides. At steady weight there was no real effect, and HDL (good cholesterol) fell by 3.7 mg/dL.
Anyone reading the blood pressure result as proof it prevents heart disease. No trial of this diet has recorded a heart attack, a stroke or a death in either group.

Questions

How much does DASH actually lower blood pressure?: 5.5 mmHg on the top number and 3.0 on the bottom, against a typical American diet, in a study where all food was provided, salt was fixed and body weight was held steady. In people who had high blood pressure it was 11.4 and 5.5 mmHg. Combined with cutting salt, it reached 11.5 mmHg on the top number in people with high blood pressure. These are among the most reliable numbers on this site, because the design removed almost everything else.
Does it prevent heart attacks and strokes?: Nobody knows, and this is the honest gap. A 2025 Cochrane review of every trial found five, with 1,397 people, and follow-up no longer than 18 months. Where heart attacks and strokes were checked, there were none in either group. Long-running studies that watched people link a high DASH score with 24 percent less heart disease and 18 percent fewer strokes. But those studies only watch people, and a questionnaire score is not the diet that was fed.
Will I lose weight on it?: Not from the diet itself. The studies behind the blood pressure result held body weight steady on purpose, because that was the point. When a weight loss program was added in a study where people ate on their own, blood pressure fell further and blood vessel measures improved more. So the weight loss was doing its own work, not the diet.
Is there anything in it that moves the wrong way?: HDL (good cholesterol) fell 3.7 mg/dL against control at steady weight, most in people who started highest. The study's own authors wrote that this could work against the heart benefit and needed more study. It has had little since. There was also no real effect on triglycerides at steady weight.
Do I need to cut sodium as well?: They were tested separately, and both worked. In the study that tested both, the diet lowered blood pressure at every salt level, and cutting salt lowered it on both diets, with the biggest effect from doing both. The two overlap rather than simply adding up. The diet's own edge was bigger at high salt than at low. And in the 2025 diabetes feeding study, the authors reported that the salt effect looked stronger than the diet effect.