Zuivelconsumptie, bloeddruk en hypertensie : observationele studies en interventieonderzoek

Diet and lifestyle play an important role in maintaining a healthy blood pressure. Whether intake of dairy products could reduce population blood pressure remains to be established. We examined the association of (specific types of) dairy food intake with blood pressure and risk of hypertension using data from two Dutch population-based cohort studies; i.e. the MORGEN study and the Rotterdam study. Blood pressure level was not consistently associated with overall dairy intake or intake of specific dairy foods in 21,553 Dutch adults from the MORGEN study. However, both in the MORGEN study and in the Rotterdam study, the risk of hypertension was reduced by ~20% in subjects who consumed more than 150 mL of low-fat dairy per day. Other dairy foods, i.e. fermented dairy, high-fat dairy, milk and milk products, and cheese, were not consistently associated with risk of hypertension. In addition, we assessed the effect of two dairy components on human blood pressure, i.e. lactotripeptides and cis-9, trans-11 conjugated linoleic acid, in controlled intervention studies. These dairy components did not affect blood pressure

Sources of dietary protein and risk of hypertension in a general Dutch population

Evidence suggests a small beneficial effect of dietary protein on blood pressure (BP), especially for plant protein. We examined the relationship between several types of dietary protein (total, plant, animal, dairy, meat and grain) and the risk of hypertension in a general population of 3588 Dutch adults, aged 26–65 years, who were free of hypertension at baseline. Measurements were done at baseline and after 5 and 10 years of follow-up. Hazard ratios (HR), with 95 % CI, for incident hypertension were obtained in tertiles of energy-adjusted protein, using time-dependent Cox regression models. Models were adjusted for age, sex, BMI, education, smoking, baseline systolic BP, dietary confounders and protein from other sources (if applicable). Mean BP was 118/76 mmHg at baseline. Protein intake was 85 (sd 22) g/d (approximately 15 % of energy) with 62 % originating from animal sources. The main sources of protein were dairy products (28 %), meat (24 %) and grain (19 %). During the follow-up, 1568 new cases of hypertension were identified (44 % of the participants). Energy-adjusted intake of total protein, plant protein and animal protein was not significantly associated with hypertension risk (all HR approximately 1·00, P>0·60). Protein from grain showed a significant inverse association with incident hypertension, with a HR of 0·85 (95 % CI 0·73, 1·00, Ptrend = 0·04) for the upper tertile ( = 18 g/d) v. the lower tertile ( <14 g/d), whereas dairy protein and meat protein were not associated with incident hypertension. In conclusion, higher intake of grain protein may contribute to the prevention of hypertension, which warrants confirmation in other population-based studies and randomised controlled trials

Lactopeptides and human blood pressure

Purpose of review: Since the mid-1990s, a number of randomized controlled trials have been published that showed an antihypertensive effect of peptides derived from milk. Research has mainly focused on isoleucine-proline-proline and valine-proline-proline (IPP + VPP), two lactotripeptides that can inhibit the angiotensin-converting enzyme (ACE) in vitro. In Finnish and Japanese subjects with (mild) hypertension, systolic blood pressure (SBP) reductions of approximately 5 mmHg were reported during 4-12 weeks of IPP + VPP supplementation. This review was performed to summarize new data from human intervention studies. Recent findings: The effect of lactotripeptides on blood pressure has recently been examined in six double-blind, placebo-controlled trials that involved a total of 780 subjects with high-normal blood pressure or untreated hypertension from the UK and The Netherlands. Intervention periods lasted 4-8 weeks, and IPP + VPP intake ranged from 2 to 10 mg/day. Contrary to earlier trials, there was little evidence for an antihypertensive effect of IPP + VPP. Furthermore, no ACE inhibition was observed in vivo. Summary: Recent data do not support a role for lactotripeptides in blood pressure regulation. However, we cannot exclude a beneficial effect in hypertensive subjects from specific populations (e.g. Finland, Japan). Should this be confirmed, more research is needed on mechanisms other than the renin-angiotensin-aldosterone system that could be involve

The effect of conjugated linoneic acid, a natural trans fat from milk and meat, on human blood pressure: results from a randomized crossover feeding study

Cis-9, trans-11 conjugated linoleic acid (CLA) is a natural trans fatty acid that is largely restricted to ruminant fats and consumed in foods and supplements. Its role in blood pressure (BP) regulation is still unclear. We examined the effect of cis-9, trans-11 CLA on BP compared with oleic acid. A total of 61 healthy volunteers were sequentially fed each of 3 diets for 3 weeks, in random order, for a total of 9 weeks. The diets were identical except for 7% of energy (18.9¿g in a diet of 10¿MJ¿day–1) that was provided either by oleic acid, by industrial trans fatty acids or by cis-9, trans-11 CLA. We measured BP on two separate days at the end of each intervention period. At baseline, mean BP was 113.8±14.4¿mm¿Hg systolic and 66.3±9.6¿mm¿Hg diastolic. The effect of the CLA diet compared with the oleic acid diet was 0.11¿mm¿Hg (95% confidence interval: -1.27, 1.49) systolic and -0.45¿mm¿Hg (-1.63, 0.73) diastolic. After the industrial trans fatty acid diet, the effect was 1.13¿mm¿Hg (-0.25, 2.51) systolic and -0.44¿mm¿Hg (-1.62, 0.73) diastolic compared with the oleic acid diet. Our study suggests that short-term high intakes of cis-9,trans-11 CLA do not affect BP in healthy volunteer