The DASH Diet Explained: What It Is + Health Benefits

Orignally Posted  May 2018 / Updated February 2023

What Is the DASH Diet?

DASH is an acronym for "Dietary Approaches to Stop Hypertension," as the diet was developed to help lower blood pressure. The main features of the DASH diet are that it is low in salt (sodium chloride), cholesterol, and saturated fat and rich in fruits, vegetables, dietary fiber, potassium, calcium, and magnesium. 

Health Benefits of the DASH Diet

Several extensive studies have shown that the DASH diet may help lower blood pressure and produce other health benefits.1-5 There are two versions of the DASH diet: one version limits the amount of sodium to 2,400 mg per day, and the other lower-sodium version, restricts daily sodium intake to no more than 1,500 mg. Excessive dietary salt (sodium chloride) intake increases the risk of high blood pressure, heart attack or stroke, and kidney disease. 

The first study with the DASH diet produced results even though it did not require either sodium restriction or weight loss, two well-recognized and effective key dietary tools to lower blood pressure.2 The second study from the DASH research team found that adding sodium restriction produced even better results. An intermediate restriction of 2,400 mg per day and a lower intake of 1,500 mg per day were tested.2 The lower sodium level produced the best result. In people with normal blood pressure (120/80 mmHg), the DASH diet with the lower-sodium DASH diet reduced systolic blood pressure (the first number) by 7.1 mmHg. The lower-sodium DASH diet produced an 11.5 mmHg reduction in those with high blood pressure. 

Since these initial two studies, numerous other clinical evaluations of the DASH diet have been conducted, including reducing the risk or showing beneficial effects in other health conditions, including diabetes, cognitive decline, Alzheimer's disease, and other chronic diseases.5-7 The DASH diet has also shown improved health and outcomes during pregnancy.8

How Do You Follow the DASH Diet?

The DASH diet has a daily requirement of six to eight servings of grains, four or five servings of vegetables, four or five servings of fruits, two or three servings of dairy, and up to six servings of lean meat, fish, or poultry. Seeds, legumes, and nuts should only be eaten four or five times a week because they are high in calories despite being good sources of protein, potassium, and magnesium. 

The DASH diet does not forbid any food outright but restricts the number of servings a person may have. For example, a person may only eat five servings of sweets per week. Since alcohol can increase blood pressure, men should have no more than two drinks daily, and women should limit themselves to one drink daily.

While the DASH diet is technically not designed to promote weight loss, many people are able to manage weight simply because they eat healthier foods and significantly less sugar and salt. These dietary changes can help improve blood sugar control, additionally helping both metabolism and appetite control. 

The DASH diet also encourages people to make changes gradually. For example, a person can add progressively a serving or two of vegetables to their diet each week. Gradual changes prevent digestive tract upsets like bloating, which drastic changes can cause.

References:

1. Sacks FM, Appel LJ, Moore TJ, Obarzanek E, Vollmer WM, Svetkey LP, Bray GA, Vogt TM, Cutler JA, Windhauser MM, Lin PH, Karanja N. A dietary approach to prevent hypertension: a review of the Dietary Approaches to Stop Hypertension (DASH) Study. Clin Cardiol. 1999 Jul;22(7 Suppl):III6-10.
2. Sacks FM, Svetkey LP, Vollmer WM, et al. Effects on blood pressure of reduced dietary sodium and the Dietary Approaches to Stop Hypertension (DASH) diet. DASH-Sodium Collaborative Research Group. N Engl J Med 2001; 344:3-10.
3. Filippou CD, Tsioufis CP, Thomopoulos CG, et al. Dietary Approaches to Stop Hypertension (DASH) Diet and Blood Pressure Reduction in Adults with and without Hypertension: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Adv Nutr. 2020 Sep 1;11(5):1150-1160. 
4. Chiavaroli L, Viguiliouk E, Nishi SK, Blanco Mejia S, Rahelić D, Kahleová H, Salas-Salvadó J, Kendall CW, Sievenpiper JL. DASH Dietary Pattern and Cardiometabolic Outcomes: An Umbrella Review of Systematic Reviews and Meta-Analyses. Nutrients. 2019 Feb 5;11(2):338.
5. Lari A, Sohouli MH, Fatahi S, Cerqueira HS, Santos HO, Pourrajab B, Rezaei M, Saneie S, Rahideh ST. The effects of the Dietary Approaches to Stop Hypertension (DASH) diet on metabolic risk factors in patients with chronic disease: A systematic review and meta-analysis of randomized controlled trials. Nutr Metab Cardiovasc Dis. 2021 Sep 22;31(10):2766-2778.
6. Shirani F, Salehi-Abargouei A, Azadbakht L. Effects of Dietary Approaches to Stop Hypertension (DASH) diet on some risk for developing type 2 diabetes: a systematic review and meta-analysis on controlled clinical trials. Nutrition. 2013 Jul-Aug;29(7-8):939-47.
7. van den Brink AC, Brouwer-Brolsma EM, Berendsen AAM, van de Rest O. The Mediterranean, Dietary Approaches to Stop Hypertension (DASH), and Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND) Diets Are Associated with Less Cognitive Decline and a Lower Risk of Alzheimer's Disease-A Review. Adv Nutr. 2019 Nov 1;10(6):1040-1065. Doi: 10.1093/advances/nmz054. PMID: 31209456; PMCID: PMC6855954.
8. Li S, Gan Y, Chen M, et al. Effects of the Dietary Approaches to Stop Hypertension (DASH) on Pregnancy/Neonatal Outcomes and Maternal Glycemic Control: A Systematic Review and Meta-analysis of Randomized Clinical Trials. Complement Ther Med. 2020 Nov;54:102551.