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The role of dietary protein in blood pressure regulation

Teunissen-Beekman, Karianna F.M.a,b; van Baak, Marleen A.a,b

doi: 10.1097/MOL.0b013e32835b4645
NUTRITION AND METABOLISM: Edited by Paul Nestel and Ronald P. Mensink

Purpose of review Despite a considerable amount of research, the blood pressure (BP) lowering effect of dietary proteins is still not fully established. This review discusses the most recent findings on BP lowering of dietary proteins and protein sources, the possible mechanisms and the safety of increasing protein intake.

Recent findings Recent short-term, strictly controlled, randomized clinical trials show a BP lowering effect of increased protein intake. Longer-term trials, however, show inconsistent results. Because all recent trials exchanged carbohydrates, and not fats, for proteins, the question remains whether potential beneficial effects of high protein diets are due to increased protein intake or decreased carbohydrate intake. No clear differences between plant protein and animal protein are found in observational studies, and trials comparing plant versus animal protein are lacking. Different protein sources may lower BP via different mechanisms, which might explain divergent findings. Potential harms of high protein diets are not confirmed in recent trials in healthy persons.

Summary Increasing dietary protein intake or decreasing carbohydrate intake within reasonable limits may be beneficial for BP. The most and least beneficial protein sources still need to be determined.

aDepartment of Human Biology, NUTRIM School for Nutrition, Toxicology and Metabolism, Maastricht University, Maastricht

bTop Institute Food and Nutrition, Wageningen, The Netherlands

Correspondence to Marleen van Baak, PhD, Visit address: Universiteitssingel 50 6229 ER Maastricht, The Netherlands, P.O. Box 616, 6200 MD Maastricht, The Netherlands. Tel: +31 0 43 38 81630; fax: +31 0 43 36 70 976; e-mail:

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Many beneficial effects have been ascribed to dietary protein [1,2]. Satiating and lean body mass sparing effects make high protein diets popular in weight loss and weight management programs [3]. Another favorable effect of dietary proteins may be improvement of blood pressure (BP) and cardiovascular health [4,5]. A systematic review of observational and intervention studies until June 2010 concluded that dietary protein may have a small beneficial effect on BP. Strongest evidence for this effect came from randomized controlled trials, which may be due to better controlled food intake and reduced risk of residual confounding in trials compared with observational studies [6]. However, since the publication of this review [6], new studies have been published on the BP lowering effects of high protein diets. The most recent evidence will be discussed in this review. Beneficial protein sources and BP lowering mechanisms are also addressed. In addition, recent studies on possible adverse effects of high protein diets are discussed. Most of the studies mentioned in this article increased protein intake from 15%, which is considered normal, to 25–30% of energy intake. Thus, a high protein diet of 2000 kcal per day would increase protein intake from the normal value of 74 g per day to a maximum of 148 g per day.

Recently published short-term trials found a BP lowering effect of dietary proteins. The randomized clinical trial on the effects of proteins on blood pressure found that isoenergetically replacing 60 g per day maltodextrin for a protein mixture (30% egg protein, 30% milk protein, 20% soy protein, 20% pea protein) for 4 weeks lowered SBP (−4.9 mmHg, P = 0.005) and DBP (−2.7 mmHg, P = 0.05) [7▪]. Another randomized trial found that supplementation of 40 g per day soy protein or milk protein for 8 weeks compared with a complex carbohydrate lowered SBP (−2.0 mmHg, P = 0.002 and −2.7 mmHg, P = 0.001, respectively), with no differences between the protein sources [8▪▪]. In contrast, longer trials show less clear effects. Supplementation with 30 g per day of whey protein compared with maltodextrin did not lower BP in elderly women after either 1 or 2 years of supplementation [9▪▪]. In type 2 diabetic patients, 12 months (3 months caloric restriction and 9 months weight maintenance) of dietary advice for a high protein diet (30% protein, 40% carbohydrate) versus high carbohydrate diet (15% protein, 55% carbohydrate) reduced SBP more after 3 months (−3.0 mmHg, P = 0.04) as well as after 12 months (−4.3 mmHg, P = 0.05) in the high protein group. However, these differences were no longer statistically significant after stringent corrections for multiple testing [10]. Another study found no differences in BP after 6–18 weeks on a high protein diet (131 g per day), a high carbohydrate diet, a high cereal fiber diet and a mixed diet with increased protein and fiber content [11]. Reasons that long-term studies found no effects may be decreased dietary compliance [11], higher dropout rates [12], or weakening of the short-term hypotensive effects of increased protein intake in the long term. More detailed time course trials are needed to study changes in BP during high protein diets over time. Weight loss trials with high protein diets are also inconclusive. One large trial found no effects of high protein diets [13], whereas the other found significantly lower DBP (−3.7 mmHg, P = 0.01) [14].

Box 1

Box 1

Since the Omniheart trial in 2005 [15], the question rose whether the beneficial effects of high protein diets on BP are due to increased protein content or due to reduced carbohydrate content [6]. The Omniheart trial, a large well controlled intervention trial, suggested that lowering carbohydrate intake rather than increasing protein intake may lower BP, because only increasing protein intake at the expense of carbohydrates, but not at the expense of fat, reduced SBP [15]. As all abovementioned studies compared dietary protein with carbohydrates, this question remains unanswered. Only one other small study [16] compared protein with fat intake and found, in contrast to the Omniheart trial, that increased protein intake also lowered BP compared with fat. Larger trials are necessary to confirm this. Therefore, the question whether the beneficial effects of high protein diets on BP are due to increased protein content or due to reduced carbohydrate content [6] has not been resolved yet.

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Altorf-van der Kuil et al.[6] concluded, based on observational studies, that the small beneficial effect of dietary protein on BP was mainly attributable to plant protein [6]. Additional findings in a Dutch cross-sectional sample confirmed that higher plant protein intake was associated with lower BP, whereas no clear associations were found between total protein or animal protein intake and BP [17]. A cross-sectional study in Iran found that the ratio between animal and plant protein intake was not associated with BP [18]. Also a prospective Dutch cohort study found no association of total protein, plant protein or animal protein with risk for hypertension. Only protein intake from grain was inversely associated with incident hypertension [19]. A 2-year prospective cohort study suggested a beneficial effect of plant versus animal proteins on BP [20▪]. Quartiles of methionine and alanine intake were directly associated with BP, whereas quartiles of threonine and histidine intake showed an inverse association. Plant proteins have a lower ratio of methionine and alanine to threonine and histidine compared with animal proteins [20▪].

BP lowering effects of specific animal and plant protein sources have also been investigated in trials. A meta-analysis of randomized controlled trials found that soy protein lowers BP compared with carbohydrates (SBP −4.5 mmHg, P = 0.002, DBP −3.0 mmHg, P = 0.004), but this BP reduction tended to be smaller and not significant when soy protein was compared with milk proteins (SBP −2.0 mmHg, P = 0.18, DBP −1.3 mmHg, P = 0.13) [21▪]. Soy foods are thought to be hypotensive due to their protein and flavonoid content. Lupin is a legume high in protein and fiber. Consumption of products containing lupin flour (16–20 g protein, 11 g fiber per 100 g), compared with wheat flour (4–11 g protein, 3–5 g fiber per 100 g), during 4 months of weight loss and 8 months of ad libitum weight maintenance reduced 24 h ambulatory BP (SBP −1.3 mmHg, DBP −1.0 mmHg, both P = 0.02) [22]. Many [23–26], but not all [27] recent observational studies found beneficial effects of dairy or low-fat dairy intake on BP. Recent randomized trials are inconclusive. One trial found that SBP was lowered after 8 weeks of low-fat dairy consumption (−2.9 mmHg, P = 0.03) [28], whereas another study found no effect on BP after 6 months of increased low-fat dairy consumption (0.9 mmHg, P = 0.51) [29]. Dairy foods may lower BP because of their protein content, their micronutrient content and the formation of angiotensin converting enzyme (ACE) inhibiting bioactive peptides in the gastrointestinal tract [25,30].

Differing amino acid compositions of animal and plant proteins may explain differences in their BP lowering effects. An overview of the effects of different amino acids on BP is provided in the review by Vasdev and Stuckless [5]. Two additional reviews, on the BP lowering effects of taurine and arginine respectively, have been published recently. Taurine is an amino acid-like component of foods of animal origin, which has beneficial effects on BP and the vasculature [31]. Arginine, present in animal and plant proteins, was found to have hypotensive effects according to a meta-analysis of 11 randomized placebo-controlled trials [32].

Thus, although observational studies suggest that plant protein intake may be more beneficial for BP than animal protein, trials have, thus, far not confirmed such general difference. Further randomized controlled trials are needed to investigate the hypotensive effect of specific proteins, peptides and amino acids.

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Understanding of the mechanisms by which dietary proteins, peptides and amino acids modulate BP, also discussed by Vasdev and Stuckless [5], can provide further insight into which sources of dietary proteins may lower BP. BP is a product of cardiac output and total peripheral resistance (TPR). Thus, BP lowering mechanisms act via these parameters. One BP lowering mechanism may be ACE inhibition by bioactive peptides. ACE inhibition results in reduced angiotensin II formation, reduced vasoconstriction and lower TPR and BP [33]. Studies with milk-derived ACE inhibiting peptides are inconsistent [34,35]. A recent review [33] and meta-analysis [36] both pointed out that even though earlier research has shown promising results, many recent studies could not demonstrate a BP lowering effect or an ACE inhibiting effect of lactotripeptides. An acute study found that active milk (containing bioactive tripeptides and plant sterols) lowered BP postprandially for 8 h compared with control milk. However, the renin–angiotensin system was not affected systemically. Higher urinary NO values and cyclic guanosine monophosphate excretion suggested that improved endothelial function may have reduced BP [37]. Bioactive peptides from other sources apart from milk are being developed and tested for their effects on BP and ACE inhibition [38,39]. However, their effects need to be confirmed in large randomized trials with humans. Although systemic ACE inhibition is usually not found, this does not exclude a role of local ACE inhibition (for example, in the gastrointestinal tract) in the BP lowering effect of bioactive peptides. Taken together, recent trials and reviews do not support the idea that bioactive peptides inhibit ACE systemically. In addition, in the light of recent studies a potential BP lowering effect of bioactive peptides also remains controversial.

Another BP lowering mechanism is arginine-induced vasodilation with arginine serving as a substrate for NO production. L-arginine may only augment NO production when levels of asymmetric dimethylarginine (ADMA), an endogenous NO synthase inhibitor, are elevated. Physiological concentrations of plasma arginine may be sufficient for saturating the NO synthase pathway when ADMA levels are normal [40]. Tryptophan may also reduce BP by augmenting NO production. Tryptophan is a precursor of serotonin, which may stimulate NO-synthase via yet unknown mechanisms [41]. Tryptophan may also modulate BP by reducing epinephrine and norepinephrine release [5].

Despite these and other [5] BP lowering effects associated with dietary protein intake, acute BP responses to protein consumption compared with other macronutrients are not always in line with the chronic hypotensive effect of dietary protein. For instance, isoenergetic breakfasts supplemented with 45 g casein, whey or glucose did not differ in 6 h postprandial response of BP, augmentation index and inflammatory markers [42▪▪]. Although 60 g per day of whey protein isolate during 20 weeks (8 weeks weight loss, 12 weeks ad libitum diet) reduced SBP compared with the control (carbohydrate) diet [43]. Another acute study found that postprandial TPR and mean arterial pressure (MAP) were decreased in elderly patients after consumption of meals composed of high carbohydrate or high fat foods, but not after an isoenergetic meal composed of high protein foods. The absence of a response after the protein meal was ascribed to differences in postprandial gut hormones. However, these were not measured [44▪▪]. Interactions of dietary proteins with the gastrointestinal tract and release of vasoactive hormones, such as glucagon-like-peptide-1 (GLP-1), glucose-dependent insulinotropic polypeptide (GIP) and insulin, from the gastrointestinal tract have been reviewed recently [45▪].

In summary, dietary proteins may lower BP via several mechanisms. However, postprandial changes in BP after protein consumption are not necessarily in line with long-term effects. Divergent postprandial BP responses may be explained by differences in the degree of vasodilation, mediated by NO, ACE inhibition or gastrointestinal hormones, and differences in the compensatory response of cardiac output, although this mechanism has hardly been studied so far. Further research is necessary to explore mechanisms involved in postprandial responses to dietary protein and to find out whether and how differences in acute responses are linked to differences in long-term effects of increased protein intake.

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A concern of high protein intake is that it may be harmful for renal function, especially in vulnerable groups. Therefore, patients with chronic renal failure are advised to consume 0.6–0.75 g protein/kg body weight per day. This amount of protein intake should be enough to maintain a healthy nutritional status, although limiting possible adverse effects of high protein intake [46]. It has been suggested that mainly animal protein may be harmful for kidney function [47]. One of the reasons why increased protein intake may negatively affect renal function and BP is the increased acid load associated with high protein intake. This could introduce a vicious cycle because acid load may lead to kidney damage and hypertension, which are interrelated [48]. Indeed, increased protein intake was directly associated with net acid excretion in a cross-sectional sample of renal transplant recipients, but no associations were observed between net acid excretion and acidosis related complications like hypertension and insulin resistance in this susceptible group [49]. Furthermore, no association between dietary acid load and risk of hypertension was found in a Dutch prospective cohort [50].

Three months on a high protein weight loss diet was shown to induce hyperfiltration [51▪▪]. Hyperfiltration is hypothesized to be a precursor of intraglomerular hypertension leading to albuminuria. Glomerular filtration rate (GFR) then falls progressively, which may lead, in the long run, to end-stage renal failure [52]. However, no adverse effects were found on GFR, albuminuria or fluid and electrolyte balance after 2 years on the high protein weight loss diet in healthy obese patients [51▪▪]. This could be because increased GFR with high protein intake is associated with increased renal size [53].

It has been suggested that colonic health may be adversely affected by high protein diets characterized by high meat intake. Four weeks on high protein (138 g per day) weight loss diets increased the amount of fecal carcinogenic N-nitroso compounds (NOCs) [54▪]. Further analyses revealed that the amount of fecal NOC was directly associated with meat intake and nitrate intake (from vegetables) and inversely associated with energy intake, vitamin C intake and nonstarch polysaccharides [55]. This suggests that both increased meat protein intake and low carbohydrate intake may be harmful for colonic health. Other studies also suggested that a very low carbohydrate content in high protein diets may increase the risk for all-cause mortality [56], cardiovascular disease [57] and type 2 diabetes [58].

In summary, concerns still exist for the safety of high protein diets, especially in vulnerable subgroups, due to increased acid loading and hyperfiltration. However, recent studies found that increased acid load and hyperfiltration induced by high protein diets may not be as harmful as initially thought. In addition other possible adverse effects from high protein diets, like decreased colonic health, may arise from the low carbohydrate intake characterizing these diets rather than the high protein intake per se.

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Randomized trials, especially long-term trials, remain inconclusive on the BP lowering effects of dietary proteins. This may result from different protein sources affecting differing hypotensive mechanisms. Available evidence shows no clear differences in the hypotensive effects of plant protein intake versus animal protein intake. Acute studies may give insight into their hypotensive mechanisms but are not easily translated to long-term effects. Evidence suggests that it may be safe for kidney function to increase protein intake. The question whether it is increased protein intake or decreased carbohydrate intake that affects BP has not yet been answered.

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TI Food and Nutrition is a public private partnership of science, industry and government conducting strategic research in food and nutrition (

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Conflicts of interest

There are no conflicts of interest.

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Papers of particular interest, published within the annual period of review, have been highlighted as:

  • ▪ of special interest
  • ▪▪ of outstanding interest

Additional references related to this topic can also be found in the Current World Literature section in this issue (pp. 92–93).

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1. Sousa GT, Lira FS, Rosa JC, et al. Dietary whey protein lessens several risk factors for metabolic diseases: a review. Lipids Health Dis 2012; 11:67.
2. Santesso N, Akl EA, Bianchi M, et al. Effects of higher- versus lower-protein diets on health outcomes: a systematic review and meta-analysis. Eur J Clin Nutr 2012; 66:780–788.
3. Johnstone AM. Safety and efficacy of high-protein diets for weight loss. Proc Nutr Soc 2012; 71:339–349.
4. Cam A, de Mejia EG. Role of dietary proteins and peptides in cardiovascular disease. Mol Nutr Food Res 2012; 56:53–66.
5. Vasdev S, Stuckless J. Antihypertensive effects of dietary protein and its mechanism. Int J Angiol 2010; 19:e7–e20.
6. Altorf-van der Kuil W, Engberink MF, Brink EJ, et al. Dietary protein and blood pressure: a systematic review. PLoS One 2010; 5:e12102.
7▪. 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; 95:966–971.

Randomized trial showing that a protein mixture lowers BP in 4 weeks compared with carbohydrate.

8▪▪. He J, Wofford MR, Reynolds K, et al. Effect of dietary protein supplementation on blood pressure: a randomized, controlled trial. Circulation 2011; 124:589–595.

Randomized trial showing that soy and milk protein isolate equally lower BP compared with carbohydrate in 8 weeks.

9▪▪. Hodgson JM, Zhu K, Lewis JR, et al. Long-term effects of a protein-enriched diet on blood pressure in older women. Br J Nutr 2012; 107:1664–1672.

Randomized trial showing no effects on BP after 1 and 2 year of whey protein supplementation.

10. Larsen RN, Mann NJ, Maclean E, Shaw JE. The effect of high-protein, low-carbohydrate diets in the treatment of type 2 diabetes: a 12 month randomised controlled trial. Diabetologia 2011; 54:731–740.
11. Weickert MO, Roden M, Isken F, et al. Effects of supplemented isoenergetic diets differing in cereal fiber and protein content on insulin sensitivity in overweight humans. Am J Clin Nutr 2011; 94:459–471.
12. Crichton GE, Howe PR, Buckley JD, et al. Long-term dietary intervention trials: critical issues and challenges. Trials 2012; 13:111.
13. Campbell DD, Meckling KA. Effect of the protein:carbohydrate ratio in hypoenergetic diets on metabolic syndrome risk factors in exercising overweight and obese women. Br J Nutr 2012. doi: 10.1017/S0007114511007215.
14. Te Morenga LA, Levers MT, Williams SM, et al. Comparison of high protein and high fiber weight-loss diets in women with risk factors for the metabolic syndrome: a randomized trial. Nutr J 2011; 10:40.
15. 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; 294:2455–2464.
16. Papakonstantinou E, Triantafillidou D, Panagiotakos DB, et al. A high-protein low-fat diet is more effective in improving blood pressure and triglycerides in calorie-restricted obese individuals with newly diagnosed type 2 diabetes. Eur J Clin Nutr 2010; 64:595–602.
17. Altorf-van der Kuil W, Engberink MF, Vedder MM, et al. Sources of dietary protein in relation to blood pressure in a general Dutch population. PLoS One 2012; 7:e30582.
18. Mirmiran P, Hajifaraji M, Bahadoran Z, et al. Dietary protein intake is associated with favorable cardiometabolic risk factors in adults: Tehran Lipid and Glucose Study. Nutr Res 2012; 32:169–176.
19. Altorf-van der Kuil W, Engberink MF, Geleijnse JM, et al. Sources of dietary protein and risk of hypertension in a general Dutch population. Br J Nutr 2012. doi: 10.1017/S0007114512000049.
20▪. Tuttle KR, Milton JE, Packard DP, et al. Dietary amino acids and blood pressure: a cohort study of patients with cardiovascular disease. Am J Kidney Dis 2012; 59:803–809.

Two-year prospective cohort study adressing associations between intake of amino acids and BP.

21▪. Dong JY, Tong X, Wu ZW, et al. Effect of soya protein on blood pressure: a meta-analysis of randomised controlled trials. Br J Nutr 2011; 106:317–326.

Meta-analysis showing that soy protein intake reduces BP compared with control diets.

22. Belski R, Mori TA, Puddey IB, et al. Effects of lupin-enriched foods on body composition and cardiovascular disease risk factors: a 12-month randomized controlled weight loss trial. Int J Obes (Lond) 2011; 35:810–819.
23. Crichton GE, Elias MF, Dore GA, et al. Relations between dairy food intake and arterial stiffness: pulse wave velocity and pulse pressure. Hypertension 2012; 59:1044–1051.
24. Rangan AM, Flood VL, Denyer G, et al. The effect of dairy consumption on blood pressure in mid-childhood: CAPS cohort study. Eur J Clin Nutr 2012; 66:652–657.
25. Ralston RA, Lee JH, Truby H, et al. A systematic review and meta-analysis of elevated blood pressure and consumption of dairy foods. J Hum Hypertens 2012; 26:3–13.
26. Vernay M, Aidara M, Salanave B, et al. Diet and blood pressure in 18–74-year-old adults: the French Nutrition and Health Survey (ENNS, 2006–2007). J Hypertens 2012; 30:1920–1927.
27. Heraclides A, Mishra GD, Hardy RJ, et al. Dairy intake, blood pressure and incident hypertension in a general British population: the 1946 birth cohort. Eur J Nutr 2012; 51:583–591.
28. van Meijl LE, Mensink RP. Low-fat dairy consumption reduces systolic blood pressure, but does not improve other metabolic risk parameters in overweight and obese subjects. Nutr Metab Cardiovasc Dis 2011; 21:355–361.
29. Crichton GE, Howe PR, Buckley JD, et al. Dairy consumption and cardiometabolic health: outcomes of a 12-month crossover trial. Nutr Metab (Lond) 2012; 9:19.
30. McGrane MM, Essery E, Obbagy J, et al. Dairy consumption, blood pressure, and risk of hypertension: an evidence-based review of recent literature. Curr Cardiovasc Risk Rep 2011; 5:287–298.
31. Abebe W, Mozaffari MS. Role of taurine in the vasculature: an overview of experimental and human studies. Am J Cardiovasc Dis 2011; 1:293–311.
32. Dong JY, Qin LQ, Zhang Z, et al. Effect of oral L-arginine supplementation on blood pressure: a meta-analysis of randomized, double-blind, placebo-controlled trials. Am Heart J 2011; 162:959–965.
33. Ricci-Cabello I, Herrera MO, Artacho R. Possible role of milk-derived bioactive peptides in the treatment and prevention of metabolic syndrome. Nutr Rev 2012; 70:241–255.
34. Cicero AF, Rosticci M, Ferroni A, et al. Predictors of the short-term effect of isoleucine-proline-proline/valine-proline-proline lactotripeptides from casein on office and ambulatory blood pressure in subjects with pharmacologically untreated high-normal blood pressure or first-degree hypertension. Clin Exp Hypertens 2012. doi: 10.3109/10641963.2012.681731.
35. Jauhiainen T, Niittynen L, Oresic M, et al. Effects of long-term intake of lactotripeptides on cardiovascular risk factors in hypertensive subjects. Eur J Clin Nutr 2012; 66:843–849.
36. Usinger L, Reimer C, Ibsen H. Fermented milk for hypertension. Cochrane Database Syst Rev 2012; 4:CD008118.
37. Turpeinen AM, Ehlers PI, Kivimaki AS, et al. Ile-Pro-Pro and Val-Pro-Pro tripeptide-containing milk product has acute blood pressure lowering effects in mildly hypertensive subjects. Clin Exp Hypertens 2011; 33:388–396.
38. Li H, Prairie N, Udenigwe CC, et al. Blood pressure lowering effect of a pea protein hydrolysate in hypertensive rats and humans. J Agric Food Chem 2011; 59:9854–9860.
39. Udenigwe CC, Adebiyi AP, Doyen A, et al. Low molecular weight flaxseed protein-derived arginine-containing peptides reduced blood pressure of spontaneously hypertensive rats faster than amino acid form of arginine and native flaxseed protein. Food Chemistry 2012; 132:468–475.
40. Alvares TS, Conte-Junior CA, Silva JT, Flosi Paschoalin VM. Acute L-Arginine supplementation does not increase nitric oxide production in healthy subjects. Nutr Metabol 2012; 9:54.
41. Watts SW, Morrison SF, Davis RP, Barman SM. Serotonin and blood pressure regulation. Pharmacol Rev 2012; 64:359–388.
42▪▪. Pal S, Ellis V. Acute effects of whey protein isolate on blood pressure, vascular function and inflammatory markers in overweight postmenopausal women. Br J Nutr 2011; 105:1512–1519.

Acute study showing no differences in BP, vascular function and inflammatory markers in 6 h after breakfasts supplemented with whey protein, casein protein or carbohydrate.

43. Aldrich ND, Reicks MM, Sibley SD, et al. Varying protein source and quantity do not significantly improve weight loss, fat loss, or satiety in reduced energy diets among midlife adults. Nutr Res 2011; 31:104–112.
44▪▪. Ferreira-Filho SR, de Castro Rodrigues Ferreira AC, de Oliveira PC. Systemic hemodynamic changes in young and elderly normotensive individuals after ingestion of meals with high lipid, protein, and carbohydrate contents. Blood Press Monit 2012; 17:110–115.

Acute study showing no changes in BP 1 h after protein consumption in elderly and young patients, whereas carbohydrate and fat ingestion reduced BP.

45▪. Jahan-Mihan A, Luhovyy BL, El Khoury D, Anderson GH. Dietary proteins as determinants of metabolic and physiologic functions of the gastrointestinal tract. Nutrients 2011; 3:574–603.

Review addressing differential interactions of protein sources with the gastrointestinal tract.

46. K/DOQI. Clinical practice guidelines for nutrition in chronic renal failure. K/DOQI, National Kidney Foundation. Am J Kidney Dis 2000; 35:S1–S140.
47. Odermatt A. The Western-style diet: a major risk factor for impaired kidney function and chronic kidney disease. Am J Physiol Renal Physiol 2011; 301:F919–F931.
48. van den Berg E, Hospers FA, Navis G, et al. Dietary acid load and rapid progression to end-stage renal disease of diabetic nephropathy in Westernized South Asian people. J Nephrol 2011; 24:11–17.
49. van den Berg E, Engberink MF, Brink EJ, et al. Dietary Acid Load and Metabolic Acidosis in Renal Transplant Recipients. Clin J Am Soc Nephrol 2012. doi: 10.2215/CJN.04590512.
50. Engberink MF, Bakker SJ, Brink EJ, et al. Dietary acid load and risk of hypertension: the Rotterdam Study. Am J Clin Nutr 2012; 95:1438–1444.
51▪▪. Friedman AN, Ogden LG, Foster GD, et al. Comparative effects of low-Carbohydrate High-Protein versus low-fat diets on the kidney. Clin J Am Soc Nephrol 2012; 7:1103–1111.

Randomized trial showing no adverse outcomes on kidney function after 2 years consumption of a low carbohydrate high protein weight loss diet in obese individuals.

52. Palatini P. Glomerular hyperfiltration: a marker of early renal damage in prediabetes and prehypertension. Nephrol Dial Transplant 2012; 27:1708–1714.
53. Skov AR, Toubro S, Bulow J, et al. Changes in renal function during weight loss induced by high vs low-protein low-fat diets in overweight subjects. Int J Obes Relat Metab Disord 1999; 23:1170–1177.
54▪. Russell WR, Gratz SW, Duncan SH, et al. High-protein, reduced-carbohydrate weight-loss diets promote metabolite profiles likely to be detrimental to colonic health. Am J Clin Nutr 2011; 93:1062–1072.

Randomized trial addressing adverse effects of reduced carbohydrate content in high protein weight loss diets on colonic health.

55. Holtrop G, Johnstone AM, Fyfe C, Gratz SW. Diet composition is associated with endogenous formation of N-Nitroso compounds in obese men. J Nutr 2012; 142:1652–1658.
56. Nilsson LM, Winkvist A, Eliasson M, et al. Low-carbohydrate, high-protein score and mortality in a northern Swedish population-based cohort. Eur J Clin Nutr 2012; 66:694–700.
57. Lagiou P, Sandin S, Lof M, et al. Low carbohydrate-high protein diet and incidence of cardiovascular diseases in Swedish women: prospective cohort study. BMJ 2012; 344:e4026.
58. Simila ME, Kontto JP, Valsta LM, et al. Carbohydrate substitution for fat or protein and risk of type 2 diabetes in male smokers. Eur J Clin Nutr 2012; 66:716–721.

animal protein; blood pressure; plant protein; protein intake; safety

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