Your activity: 174 p.v.
your limit has been reached. plz Donate us to allow your ip full access, Email: sshnevis@outlook.com

Diet in the treatment and prevention of hypertension

Diet in the treatment and prevention of hypertension
Author:
John P Forman, MD, MSc
Section Editor:
George L Bakris, MD
Deputy Editor:
Eric N Taylor, MD, MSc, FASN
Literature review current through: Nov 2022. | This topic last updated: Dec 14, 2020.

INTRODUCTION — A variety of dietary modifications are beneficial in the treatment of hypertension, including reduction of sodium intake, moderation of alcohol, weight loss in the overweight or obese, and a diet rich in fruits, vegetables, legumes, and low-fat dairy products and low in snacks, sweets, meat, and saturated fat. Individual dietary factors may also reduce blood pressure (BP) [1].

Nondietary modalities of lifestyle modification should also be considered, including cessation of smoking and institution of an aerobic exercise regimen. (See "Smoking and hypertension" and "Exercise in the treatment and prevention of hypertension".)

Most of the studies on nonpharmacologic therapy evaluated only a single factor to prove its efficacy (eg, weight reduction without sodium restriction). In making recommendations to the individual patient, however, the clinician will try to modify all of the factors that may be contributing to the elevation in BP, although it is uncertain if the effects of different modifications are additive.

In those with elevated BP or stage 1 hypertension, lifestyle changes may control the BP adequately [1]. However, in those with either higher BP or additional risk (eg, diabetes or chronic kidney disease), drug therapies should first be used to more quickly and effectively control the BP. Once BP is well controlled, lifestyle changes should be strongly advised. If these are successfully achieved, reduction of medications may be possible.

This topic will review the effect of comprehensive dietary modification, as well as the effects of individual dietary interventions on BP.

COMPREHENSIVE DIETARY MODIFICATION — Many studies have examined the effects of comprehensive dietary modification, in which multiple dietary factors are modified, on blood pressure [2,3]. Most comprehensive dietary modification studies have tested dietary patterns that emphasize plant-based foods and de-emphasize animal-based foods. Among these, the two dietary patterns that have the greatest impact on blood pressure lowering and that are supported by the strongest data are the Dietary Approaches to Stop Hypertension (DASH) diet (see 'Dietary Approaches to Stop Hypertension trial' below) and a lacto-ovo vegetarian diet (which incorporates eggs and dairy products as protein sources). In a meta-analysis of 41 trials, the DASH diet and a lacto-ovo vegetarian diet reduced systolic blood pressure by 5.5 mmHg, an effect that was larger than the effects of a Mediterranean diet, a fruit-and-vegetable diet, a high-fiber diet, and a vegan diet [2].

Treatment of Mild Hypertension Study — In the Treatment of Mild Hypertension Study (TOMHS), 902 patients with mild diastolic hypertension (90 to 100 mmHg) were started on a program consisting of weight reduction, sodium and alcohol restriction, and increased physical activity. Patients were then randomly assigned to placebo or to one of five different antihypertensive drugs [4]. There were initial improvements in all of the dietary parameters that tended to diminish over time (figure 1). Despite the difficulty in maintaining optimal compliance, those patients who remained on the lifestyle program had an average 8.6/8.6 mmHg fall in blood pressure (BP) at four years.

Although the response to nonpharmacologic therapy alone was less than that seen if drug therapy were added [4], dietary modifications have the additional cardiovascular advantage of lowering plasma total and low-density lipoprotein (LDL)-cholesterol and raising high-density lipoprotein (HDL)-cholesterol. (See "Antihypertensive drugs and lipids".)

Dietary Approaches to Stop Hypertension trial — A different approach was evaluated in the Dietary Approaches to Stop Hypertension (DASH) trial [5]. Rather than evaluating sodium intake or weight loss, DASH randomly assigned 459 patients with BPs of less than 160/80 to 95 mmHg to one of three diets:

A control diet low in fruits, vegetables, and legumes and high in snacks, sweets, meats, and saturated fat.

A diet rich in fruits, vegetables, legumes and low in snacks and sweets.

A combination diet rich in fruits, vegetables, legumes, and low-fat dairy products and low in snacks, sweets, meats, and saturated and total fat (this combination diet is called the "DASH diet"). The DASH diet is comprised of four to five servings of fruit, four to five servings of vegetables, two to three servings of low-fat dairy per day, and <25 percent fat.

The following observations were noted in which the BP reductions were expressed in relation to the fall in BP seen with the control diet:

The fruits and vegetables diet reduced the BP by 2.8/1.1 mmHg, and the combination diet reduced the BP by 5.5/3.0.

These effects were more pronounced in patients with hypertension. With the combination diet, for example, the BP fell 11.4/5.5 mmHg in hypertensives versus 3.5/2.1 mmHg in the normotensives.

The antihypertensive effects were maximal by the end of week 2 with any of the diets and were then maintained for eight weeks.

Low-sodium DASH — The low-sodium DASH trial evaluated the effect of varying sodium intake in combination with consuming the DASH diet described above [6]. In this study, 412 participants were randomly assigned to a DASH or control diet and, within each diet, ate foods with three levels of sodium content (high [3.5 g], intermediate [2.3 g], and low [1.2 g]) for 30 days each. The following results were reported:

At all three levels of sodium intake in the DASH and control diets, the DASH diet resulted in lower systolic and diastolic BP compared with control. The impact of the DASH diet on relative BP reduction was more pronounced in participants with higher sodium intakes. At high, intermediate, and low levels of sodium intake, the DASH diet systolic pressure was 5.9, 5, and 2.2 mmHg lower than the control diet, respectively. Corresponding reductions in diastolic pressure were 2.9, 2.5, and 1 mmHg.

With either diet, lowering the sodium intake reduced BP levels, an effect observed among those with and without hypertension and among different races and sex.

When different phases of diet were compared, the most significant decrease in BP was observed between the high-sodium control diet and low-sodium DASH diets as a comparative overall reduction of 8.9 and 4.5 mmHg in systolic and diastolic BPs, respectively, was noted with the low-sodium DASH diet. This benefit was even more significant among hypertensive individuals. The mean fall in systolic BP was 11.5 mmHg.

Thus, the combination of a low-sodium and DASH diet resulted in the most significant benefit, with decreases in BP comparable with those observed with antihypertensive agents.

PREMIER trial — The PREMIER trial was designed to assess the additive BP effects of two different behavioral interventions [7]. In this study, 810 patients with above optimal BP (120 to 159 mmHg systolic pressure and/or 80 to 95 mmHg diastolic pressure) were randomly assigned to one of three groups: 1) "established behavioral intervention" (eg, weight loss, physical activity, and limitations in sodium and alcohol intake); 2) the DASH diet plus "established behavioral intervention"; and 3) one-time advice only. Unlike the original DASH study, the subjects prepared their own food. To assess the effects on BP of the interventions, the effect of advice only (6.6/3.8 mmHg decrease) was subtracted from the BP change in the intervention groups.

At six months, the DASH diet plus behavioral intervention produced a small additional decrease in BP versus that observed with behavioral intervention alone (4.3/2.6 mmHg and 3.7/1.7 mmHg, respectively). The prevalence of mild hypertension at study end was significantly less in the two intervention groups (12 and 17 percent in DASH plus established and established group, respectively) than in the advice-only arm (26 percent). At 18-month follow-up, the prevalence of hypertension had increased in all three groups, but remained lowest in the two intervention groups (22 and 24 percent in DASH plus established and established group, respectively, versus 32 percent in the advice only) [8]. (See 'Prevention' below.)

Overall, the absolute effects on BP of DASH plus those of behavioral intervention were not additive. Possible reasons for this less than expected effect of the DASH diet included the requirement that the subjects prepared their own food, so there was less rigorous adherence to the diet than in the other DASH studies, where all the food was provided; a large BP decrease in the advice-only control group; and a possible similar physiologic mechanism for BP lowering for both interventions [9].

Diet versus antihypertensive agents — There are limited data concerning the relative efficacy of lifestyle interventions (particularly diet) versus antihypertensive agents on BP control or cardiovascular outcomes [10].

Despite this absence of evidence of relative effectiveness, we and most experts feel that diet plays an important role in many susceptible patients in the genesis and maintenance of hypertension [11].

SALT RESTRICTION AND WEIGHT REDUCTION — The potential beneficial effects of salt restriction and, in overweight patients, weight reduction in hypertensive patients are discussed separately. (See "Salt intake, salt restriction, and primary (essential) hypertension" and "Overweight, obesity, and weight reduction in hypertension".)

OTHER DIETARY INTERVENTIONS — Potassium supplements, 40 to 80 mEq/day, lower blood pressure (BP), an effect that is largely lost in patients who are also on a low-sodium diet [12,13]. Other modalities, such as stress reduction and supplements of calcium, magnesium, or fish oil, appear to induce a small and less predictable reduction in BP in most patients [14-19].

Potassium — Potassium supplementation may modestly lower the BP. This issue is discussed separately. (See "Potassium and hypertension".)

Magnesium — Higher magnesium intake has been associated with lower BP [14,17].

Fish oil — High-dose, but not low-dose, fish oil supplements may reduce systemic BP, although the effect appears to be modest [15,19-23]. The effect of fish oil supplementation on BP and other cardiovascular risk factors is presented separately. (See "Fish oil: Physiologic effects and administration", section on 'Potential effects on cardiovascular and metabolic systems' and "Fish oil: Physiologic effects and administration", section on 'System effects'.)

Calcium — Although there appears to be an inverse relation between dietary calcium intake and BP in observational studies [24], the effect of calcium supplementation on BP is uncertain [16]. This was illustrated in a meta-analysis including 13 trials of eight weeks or longer in duration, which found that calcium supplementation modestly reduced systolic but not diastolic BP (by 2.5 mmHg); however, all but one trial were low quality [16].

The effect of supplemental calcium on BP is too small to recommend the use of calcium supplements for the therapy or prevention of hypertension. Moreover, in a community-based, prospective, longitudinal cohort study, high intake of calcium was associated with higher death rates from all causes and cardiovascular disease [25].

High-fiber diet — A higher intake of dietary fiber is associated with decreased systemic pressures [26]. Multiple meta-analyses have shown benefits with dietary fiber intake on BP [26-29]. As an example, a 2005 meta-analysis of 24 randomized, placebo-controlled trials published between 1966 and 2003 on the effects of fiber supplementation found an average fall of 1.2/1.3 mmHg with fiber intake (average dose of 11.5 g/day) [26]. More significant reductions were observed in older (greater than 40 years) and hypertensive individuals.

Protein intake — Replacing carbohydrate intake with soy (vegetable) or dairy protein may reduce BP [30-35]. As an example, one study randomly assigned 302 Chinese subjects with untreated hypertension (systolic BP between 130 to 159 mmHg) to soybean protein or carbohydrate complex control [32]. After 12 weeks, systolic and diastolic BPs were 4.3 and 2.8 mmHg lower among those taking the protein supplement, compared with the control group. There was a greater effect among those with hypertension at baseline (BP >140/90 mmHg).

Folate — An inverse association of folate intake with BP or hypertension has been shown in three large, prospective, cohort studies [36,37], as well as in several randomized trials [38-40]. In a meta-analysis of 12 randomized trials, supplemental folic acid (5 mg/day or more) significantly reduced systolic, but not diastolic, BP by 2.0 mmHg as compared with placebo [40].

Flavonoids — The beneficial effect of fruits and vegetables on BP may be due in part to an increased intake of polyphenols (eg, flavonoids). Significant sources of these compounds in Western countries include tea and cocoa products. The effect of cocoa on BP was evaluated in a 2012 Cochrane meta-analysis of 35 studies consisting of 1804 subjects [41]. At a median duration of intake of 4.4 weeks, flavanol-rich cocoa products significantly reduced both systolic and diastolic pressure compared with low-flavanol-containing cocoa powder or flavanol-free interventions (mean reduction, 1.8/1.8 mmHg). A discussion of BP and tea ingestion is presented separately. (See "Cardiovascular effects of caffeine and caffeinated beverages", section on 'Blood pressure'.)

PREVENTION — Dietary and lifestyle modifications have been evaluated in a number of studies for the prevention rather than treatment of hypertension [21,42-48]. As illustrated by the following observations, the optimal effect on blood pressure (BP) is achieved with correction of multiple contributors to hypertension, including salt intake, obesity, and excess alcohol intake. (See "Salt intake, salt restriction, and primary (essential) hypertension" and "Overweight, obesity, and weight reduction in hypertension" and "Cardiovascular benefits and risks of moderate alcohol consumption", section on 'Hypertension'.)

The relative efficacy of such interventions can be illustrated by the results of two randomized trials and a large observational study:

The Trials of Hypertension Prevention, phase II randomized 2382 men and women (aged 30 to 54 years) with a BP <140/83-89 who were 110 to 165 percent of ideal body weight [42]. The patients were randomly assigned to usual care, salt restriction, weight reduction, or both. Sodium restriction was associated with a 50 and 40 mEq decline in sodium excretion at 6 and 36 months, respectively. Sodium restriction plus weight loss was associated with a decrease in weight from baseline of 4 and 2 kg at 6 and 36 months, respectively. Compared with usual care, the BP fell at six months by 3.7/2.7 with weight loss, 2.9/1.6 with salt restriction, and 4.0/2.0 with combined therapy. These effects were attenuated at 36 months, but, at 48 months, the likelihood of progressing to hypertension was reduced with nonpharmacologic therapy (relative risk 0.78 to 0.82).

The TONE trial evaluated 975 older people (aged 60 to 80 years) who had a BP <145/<85 mmHg on one antihypertensive medication; 585 were obese [43]. The patients were randomly assigned to usual care or to salt restriction, weight loss (in obese patients), or both. Those assigned to salt restriction had a 40 mEq/day decrease in sodium excretion, while, in obese patients, a regimen of diminished caloric intake and increased physical activity was associated with a persistent weight loss of 4 to 5 kg; these parameters were unchanged in the usual-care group. After three months of intervention, withdrawal of the antihypertensive drug was attempted.

The primary endpoint was a diagnosis of high BP at one or more follow-up visits, treatment with antihypertensive drugs, or a cardiovascular event. The reduction in BP compared with usual care was 2.6/1.1 mmHg with salt restriction, 3.2/0.3 mmHg with weight loss, and 4.5/2.6 mmHg with combined therapy. The primary endpoint at 30 months occurred significantly less often with salt restriction (62 versus 76 percent with usual care), weight reduction in obese subjects (61 versus 74 percent), and combined salt restriction and weight reduction in obese subjects (56 versus 84 percent).

The importance of risk factors for primary hypertension (formerly called "essential" hypertension) in women was evaluated in a prospective cohort study of 83,882 adult women from the second Nurses' Health Study who did not have a history of hypertension, cardiovascular disease, or diabetes [44]. Six lifestyle and dietary factors were independently associated with a lower risk of developing hypertension during 14 years of follow-up: body mass index of less than 25 kg/m2, a daily mean of 30 minutes of vigorous exercise, adherence to the Dietary Approaches to Stop Hypertension (DASH) diet, modest alcohol intake, infrequent use of nonnarcotic analgesics, and intake of 400 mcg/day or more of folate [44]. The presence of all six factors was associated with a marked decrease in the risk for hypertension (hazard ratio 0.22, 95% CI 0.10-0.51).

SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Hypertension in adults".)

INFORMATION FOR PATIENTS — UpToDate offers two types of patient education materials, "The Basics" and "Beyond the Basics." The Basics patient education pieces are written in plain language, at the 5th to 6th grade reading level, and they answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials. Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are written at the 10th to 12th grade reading level and are best for patients who want in-depth information and are comfortable with some medical jargon.

Here are the patient education articles that are relevant to this topic. We encourage you to print or e-mail these topics to your patients. (You can also locate patient education articles on a variety of subjects by searching on "patient info" and the keyword(s) of interest.)

Basics topic (see "Patient education: Controlling your blood pressure through lifestyle (The Basics)")

Beyond the Basics topic (see "Patient education: High blood pressure, diet, and weight (Beyond the Basics)")

SUMMARY

There are limited data concerning the relative efficacy of lifestyle interventions (particularly diet) versus antihypertensive agents on blood pressure (BP) control or cardiovascular outcomes. Despite this absence of evidence of relative effectiveness, we and most experts feel that diet plays an important role in many susceptible patients in the genesis and maintenance of hypertension. (See 'Comprehensive dietary modification' above.)

A diet that is rich in fruits, vegetables, legumes, and low-fat dairy products and low in snacks, sweets, and meats (such as the Dietary Approaches to Stop Hypertension [DASH] diet) may lower BP and prevent hypertension. (See 'Comprehensive dietary modification' above.)

Low intake of sodium and high intake of potassium (or potassium supplementation) can reduce BP. (See "Salt intake, salt restriction, and primary (essential) hypertension" and "Potassium and hypertension".)

High-dose, but not low-dose, fish oil supplements may reduce systemic BP. (See 'Fish oil' above.)

Other dietary interventions that may be associated with reduced BP include dietary fiber, magnesium, soy (vegetable) or dairy protein intake, folate, and possibly polyphenols (eg, flavonoids). (See 'Other dietary interventions' above and "Cardiovascular effects of caffeine and caffeinated beverages", section on 'Blood pressure'.)

Dietary calcium and calcium supplements have a relatively small effect on BP. The effect of supplemental calcium on BP is too small to recommend the use of calcium supplements for the therapy or prevention of hypertension. (See 'Calcium' above.)

Dietary and lifestyle modifications have been evaluated in a number of studies for the prevention rather than treatment of hypertension. The optimal effect on BP is achieved with correction of multiple contributors to hypertension, including salt intake, obesity, and excess alcohol intake. (See "Salt intake, salt restriction, and primary (essential) hypertension" and "Overweight, obesity, and weight reduction in hypertension" and "Cardiovascular benefits and risks of moderate alcohol consumption", section on 'Hypertension'.)

ACKNOWLEDGMENT — The UpToDate editorial staff acknowledges Norman M Kaplan, MD, who contributed to an earlier version of this topic review.

  1. Whelton PK, Carey RM, Aronow WS, et al. 2017 ACC/AHA/AAPA/ABC/ACPM/AGS/APhA/ASH/ASPC/NMA/PCNA Guideline for the Prevention, Detection, Evaluation, and Management of High Blood Pressure in Adults: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines. Hypertension 2018; 71:e13.
  2. Gibbs J, Gaskin E, Ji C, et al. The effect of plant-based dietary patterns on blood pressure: a systematic review and meta-analysis of controlled intervention trials. J Hypertens 2021; 39:23.
  3. Sacks FM, Campos H. Dietary therapy in hypertension. N Engl J Med 2010; 362:2102.
  4. Neaton JD, Grimm RH Jr, Prineas RJ, et al. Treatment of Mild Hypertension Study. Final results. Treatment of Mild Hypertension Study Research Group. JAMA 1993; 270:713.
  5. Appel LJ, Moore TJ, Obarzanek E, et al. A clinical trial of the effects of dietary patterns on blood pressure. DASH Collaborative Research Group. N Engl J Med 1997; 336:1117.
  6. 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.
  7. Appel LJ, Champagne CM, Harsha DW, et al. Effects of comprehensive lifestyle modification on blood pressure control: main results of the PREMIER clinical trial. JAMA 2003; 289:2083.
  8. Elmer PJ, Obarzanek E, Vollmer WM, et al. Effects of comprehensive lifestyle modification on diet, weight, physical fitness, and blood pressure control: 18-month results of a randomized trial. Ann Intern Med 2006; 144:485.
  9. Pickering TG. Lifestyle modification and blood pressure control: is the glass half full or half empty? JAMA 2003; 289:2131.
  10. Nicolson DJ, Dickinson HO, Campbell F, Mason JM. Lifestyle interventions or drugs for patients with essential hypertension: a systematic review. J Hypertens 2004; 22:2043.
  11. Chobanian AV, Bakris GL, Black HR, et al. The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure: the JNC 7 report. JAMA 2003; 289:2560.
  12. Filippini T, Violi F, D'Amico R, Vinceti M. The effect of potassium supplementation on blood pressure in hypertensive subjects: A systematic review and meta-analysis. Int J Cardiol 2017; 230:127.
  13. Binia A, Jaeger J, Hu Y, et al. Daily potassium intake and sodium-to-potassium ratio in the reduction of blood pressure: a meta-analysis of randomized controlled trials. J Hypertens 2015; 33:1509.
  14. Kass L, Weekes J, Carpenter L. Effect of magnesium supplementation on blood pressure: a meta-analysis. Eur J Clin Nutr 2012; 66:411.
  15. Geleijnse JM, Giltay EJ, Grobbee DE, et al. Blood pressure response to fish oil supplementation: metaregression analysis of randomized trials. J Hypertens 2002; 20:1493.
  16. Dickinson HO, Nicolson DJ, Cook JV, et al. Calcium supplementation for the management of primary hypertension in adults. Cochrane Database Syst Rev 2006; :CD004639.
  17. Zhang X, Li Y, Del Gobbo LC, et al. Effects of Magnesium Supplementation on Blood Pressure: A Meta-Analysis of Randomized Double-Blind Placebo-Controlled Trials. Hypertension 2016; 68:324.
  18. Nagele E, Jeitler K, Horvath K, et al. Clinical effectiveness of stress-reduction techniques in patients with hypertension: systematic review and meta-analysis. J Hypertens 2014; 32:1936.
  19. Miller PE, Van Elswyk M, Alexander DD. Long-chain omega-3 fatty acids eicosapentaenoic acid and docosahexaenoic acid and blood pressure: a meta-analysis of randomized controlled trials. Am J Hypertens 2014; 27:885.
  20. Knapp HR, FitzGerald GA. The antihypertensive effects of fish oil. A controlled study of polyunsaturated fatty acid supplements in essential hypertension. N Engl J Med 1989; 320:1037.
  21. The effects of nonpharmacologic interventions on blood pressure of persons with high normal levels. Results of the Trials of Hypertension Prevention, Phase I. JAMA 1992; 267:1213.
  22. Bønaa KH, Bjerve KS, Straume B, et al. Effect of eicosapentaenoic and docosahexaenoic acids on blood pressure in hypertension. A population-based intervention trial from the Tromsø study. N Engl J Med 1990; 322:795.
  23. Kasim SE, Stern B, Khilnani S, et al. Effects of omega-3 fish oils on lipid metabolism, glycemic control, and blood pressure in type II diabetic patients. J Clin Endocrinol Metab 1988; 67:1.
  24. Power ML, Heaney RP, Kalkwarf HJ, et al. The role of calcium in health and disease. Am J Obstet Gynecol 1999; 181:1560.
  25. Michaëlsson K, Melhus H, Warensjö Lemming E, et al. Long term calcium intake and rates of all cause and cardiovascular mortality: community based prospective longitudinal cohort study. BMJ 2013; 346:f228.
  26. Streppel MT, Arends LR, van 't Veer P, et al. Dietary fiber and blood pressure: a meta-analysis of randomized placebo-controlled trials. Arch Intern Med 2005; 165:150.
  27. Khan K, Jovanovski E, Ho HVT, et al. The effect of viscous soluble fiber on blood pressure: A systematic review and meta-analysis of randomized controlled trials. Nutr Metab Cardiovasc Dis 2018; 28:3.
  28. Whelton SP, Hyre AD, Pedersen B, et al. Effect of dietary fiber intake on blood pressure: a meta-analysis of randomized, controlled clinical trials. J Hypertens 2005; 23:475.
  29. Khalesi S, Irwin C, Schubert M. Flaxseed consumption may reduce blood pressure: a systematic review and meta-analysis of controlled trials. J Nutr 2015; 145:758.
  30. Appel LJ, Sacks FM, Carey VJ, et al. Effects of protein, monounsaturated fat, and carbohydrate intake on blood pressure and serum lipids: results of the OmniHeart randomized trial. JAMA 2005; 294:2455.
  31. Washburn S, Burke GL, Morgan T, Anthony M. Effect of soy protein supplementation on serum lipoproteins, blood pressure, and menopausal symptoms in perimenopausal women. Menopause 1999; 6:7.
  32. He J, Gu D, Wu X, et al. Effect of soybean protein on blood pressure: a randomized, controlled trial. Ann Intern Med 2005; 143:1.
  33. He J, Wofford MR, Reynolds K, et al. Effect of dietary protein supplementation on blood pressure: a randomized, controlled trial. Circulation 2011; 124:589.
  34. Teunissen-Beekman KF, Dopheide J, Geleijnse JM, et al. Protein supplementation lowers blood pressure in overweight adults: effect of dietary proteins on blood pressure (PROPRES), a randomized trial. Am J Clin Nutr 2012; 95:966.
  35. Rebholz CM, Friedman EE, Powers LJ, et al. Dietary protein intake and blood pressure: a meta-analysis of randomized controlled trials. Am J Epidemiol 2012; 176 Suppl 7:S27.
  36. Forman JP, Rimm EB, Stampfer MJ, Curhan GC. Folate intake and the risk of incident hypertension among US women. JAMA 2005; 293:320.
  37. Xun P, Liu K, Loria CM, et al. Folate intake and incidence of hypertension among American young adults: a 20-y follow-up study. Am J Clin Nutr 2012; 95:1023.
  38. van Dijk RA, Rauwerda JA, Steyn M, et al. Long-term homocysteine-lowering treatment with folic acid plus pyridoxine is associated with decreased blood pressure but not with improved brachial artery endothelium-dependent vasodilation or carotid artery stiffness: a 2-year, randomized, placebo-controlled trial. Arterioscler Thromb Vasc Biol 2001; 21:2072.
  39. Mangoni AA, Sherwood RA, Swift CG, Jackson SH. Folic acid enhances endothelial function and reduces blood pressure in smokers: a randomized controlled trial. J Intern Med 2002; 252:497.
  40. McRae MP. High-dose folic acid supplementation effects on endothelial function and blood pressure in hypertensive patients: a meta-analysis of randomized controlled clinical trials. J Chiropr Med 2009; 8:15.
  41. Ried K, Fakler P, Stocks NP. Effect of cocoa on blood pressure. Cochrane Database Syst Rev 2017; 4:CD008893.
  42. Effects of weight loss and sodium reduction intervention on blood pressure and hypertension incidence in overweight people with high-normal blood pressure. The Trials of Hypertension Prevention, phase II. The Trials of Hypertension Prevention Collaborative Research Group. Arch Intern Med 1997; 157:657.
  43. Whelton PK, Appel LJ, Espeland MA, et al. Sodium reduction and weight loss in the treatment of hypertension in older persons: a randomized controlled trial of nonpharmacologic interventions in the elderly (TONE). TONE Collaborative Research Group. JAMA 1998; 279:839.
  44. Forman JP, Stampfer MJ, Curhan GC. Diet and lifestyle risk factors associated with incident hypertension in women. JAMA 2009; 302:401.
  45. He J, Whelton PK, Appel LJ, et al. Long-term effects of weight loss and dietary sodium reduction on incidence of hypertension. Hypertension 2000; 35:544.
  46. Stamler R, Stamler J, Gosch FC, et al. Primary prevention of hypertension by nutritional-hygienic means. Final report of a randomized, controlled trial. JAMA 1989; 262:1801.
  47. Takahashi Y, Sasaki S, Okubo S, et al. Blood pressure change in a free-living population-based dietary modification study in Japan. J Hypertens 2006; 24:451.
  48. Whelton PK, He J, Appel LJ, et al. Primary prevention of hypertension: clinical and public health advisory from The National High Blood Pressure Education Program. JAMA 2002; 288:1882.
Topic 3878 Version 32.0

References