The Longevity Project » blood pressure http://thelongevityproject.com Information center for prevention, cognition and sustainable aging Sat, 21 Nov 2009 15:07:48 +0000 http://wordpress.org/?v=2.8.6 en hourly 1 Effects of low habitual cocoa intake on blood pressure and bioactive nitric oxide: a randomized controlled trial http://thelongevityproject.com/effects-of-low-habitual-cocoa-intake-on-blood-pressure-and-bioactive-nitric-oxide-a-randomized-controlled-trial/ http://thelongevityproject.com/effects-of-low-habitual-cocoa-intake-on-blood-pressure-and-bioactive-nitric-oxide-a-randomized-controlled-trial/#comments Thu, 12 Nov 2009 17:16:19 +0000 TLP http://thelongevityproject.com/?p=516 CONTEXT: Regular intake of cocoa-containing foods is linked to lower cardiovascular mortality in observational studies. Short-term interventions of at most 2 weeks indicate that high doses of cocoa can improve endothelial function and reduce blood pressure (BP) due to the action of the cocoa polyphenols, but the clinical effect of low habitual cocoa intake on BP and the underlying BP-lowering mechanisms are unclear. OBJECTIVE: To determine effects of low doses of polyphenol-rich dark chocolate on BP. DESIGN, SETTING, AND PARTICIPANTS: Randomized, controlled, investigator-blinded, parallel-group trial involving 44 adults aged 56 through 73 years (24 women, 20 men) with untreated upper-range prehypertension or stage 1 hypertension without concomitant risk factors. The trial was conducted at a primary care clinic in Germany between January 2005 and December 2006. INTERVENTION: Participants were randomly assigned to receive for 18 weeks either 6.3 g (30 kcal) per day of dark chocolate containing 30 mg of polyphenols or matching polyphenol-free white chocolate. MAIN OUTCOME MEASURES: Primary outcome measure was the change in BP after 18 weeks. Secondary outcome measures were changes in plasma markers of vasodilative nitric oxide (S-nitrosoglutathione) and oxidative stress (8-isoprostane), and bioavailability of cocoa polyphenols. RESULTS: From baseline to 18 weeks, dark chocolate intake reduced mean (SD) systolic BP by -2.9 (1.6) mm Hg (P < .001) and diastolic BP by -1.9 (1.0) mm Hg (P < .001) without changes in body weight, plasma levels of lipids, glucose, and 8-isoprostane. Hypertension prevalence declined from 86% to 68%. The BP decrease was accompanied by a sustained increase of S-nitrosoglutathione by 0.23 (0.12) nmol/L (P < .001), and a dark chocolate dose resulted in the appearance of cocoa phenols in plasma. White chocolate intake caused no changes in BP or plasma biomarkers. CONCLUSIONS: Data in this relatively small sample of otherwise healthy individuals with above-optimal BP indicate that inclusion of small amounts of polyphenol-rich dark chocolate as part of a usual diet efficiently reduced BP and improved formation of vasodilative nitric oxide.

JAMA. 2007 Jul 4;298(1):49-60.

Taubert D, Roesen R, Lehmann C, Jung N, Schömig E.

Department of Pharmacology, University Hospital of Cologne, Cologne, Germany. dirk.taubert@medizin.uni-koeln.de

Comment in:

Click here to read
]]> http://thelongevityproject.com/effects-of-low-habitual-cocoa-intake-on-blood-pressure-and-bioactive-nitric-oxide-a-randomized-controlled-trial/feed/ 0 Effect of Cocoa and Tea Intake on Blood Pressure: A Meta-analysis http://thelongevityproject.com/effect-of-cocoa-and-tea-intake-on-blood-pressure-a-meta-analysis/ http://thelongevityproject.com/effect-of-cocoa-and-tea-intake-on-blood-pressure-a-meta-analysis/#comments Mon, 23 Apr 2007 09:55:34 +0000 TLP http://thelongevityproject.com/effect-of-cocoa-and-tea-intake-on-blood-pressure-a-meta-analysis/ Background Epidemiological evidence suggests blood pressure–lowering effects of cocoa and tea. We undertook a meta-analysis of randomized controlled trials to determine changes in systolic and diastolic blood pressure due to the intake of cocoa products or black and green tea.

Methods MEDLINE, EMBASE, SCOPUS, Science Citation Index, and the Cochrane Controlled Trials Register were searched from 1966 until October 2006 for studies in parallel group or crossover design involving 10 or more adults in whom blood pressure was assessed before and after receiving cocoa products or black or green tea for at least 7 days.

Results Five randomized controlled studies of cocoa administration involving a total of 173 subjects with a median duration of 2 weeks were included. After the cocoa diets, the pooled mean systolic and diastolic blood pressure were –4.7 mm Hg (95% confidence interval [CI], –7.6 to –1.8 mm Hg; P = .002) and –2.8 mm Hg (95% CI, –4.8 to –0.8 mm Hg; P = .006) lower, respectively, compared with the cocoa-free controls. Five studies of tea consumption involving a total of 343 subjects with a median duration of 4 weeks were selected. The tea intake had no significant effects on blood pressure. The estimated pooled changes were 0.4 mm Hg (95% CI, –1.3 to 2.2 mm Hg; P = .63) in systolic and –0.6 mm Hg (95% CI, –1.5 to 0.4 mm Hg; P = .38) in diastolic blood pressure compared with controls.

Conclusion Current randomized dietary studies indicate that consumption of foods rich in cocoa may reduce blood pressure, while tea intake appears to have no effect.

Dirk Taubert, MD, PhD; Renate Roesen, PhD; Edgar Schömig, MD
Department of Pharmacology, University Hospital of Cologne, Cologne, Germany.
Arch Intern Med. 2007;167:626-634.

FULL TEXT

]]> http://thelongevityproject.com/effect-of-cocoa-and-tea-intake-on-blood-pressure-a-meta-analysis/feed/ 0