Table 3 Characteristics of included chronic studies, including information on population studied and interventions used
|  | Study design (washout period) | Participants’ health | Number of participants | Age (yrs) | % female | Study duration | Daily cocoa intervention type/dose | Daily control intervention type | Microcirculation studied |
|---|---|---|---|---|---|---|---|---|---|
(n) Heinrich 2006 [68] | Parallel | Healthy females | n = 24 (12 per group) | 18–65 | 100% | 12 weeks (tested also at 6wks) | 18 g powder in 100 ml water Total flavs: 329mg Epicatechin: 61.1mg | 18 g powder in 100 ml water Total flavs: 26.8 g Epicatechin: 1.6mg | Cutaneous |
(b) Heiss 2015 [72] | Parallel | (b1) Healthy young (18-30yrs) | n = 22 | 26 ± 4.69 | 0% | 14 days | Cocoa beverage (7 g cocoa powder in ~ 500 ml water) Total flavs: 450mg Epicatechin: 64mg | Cocoa beverage (7 g matched powder in ~ 500 ml water) Total flavs: 0mg | Cutaneous/ skeletal muscle (forearm) |
(b2) Healthy elderly (50-80yrs) | n = 20 | 60 ± 8.94 | 0% | ||||||
(p) Farouque 2006 [67] | Parallel | CAD patients | CFs: n = 20 Control: n = 20 | CFs:61 ± 9 Control: 61 ± 8 | CFs: 35% Control: 15% | 6 weeks | Chocolate bar and cocoa beverage; Total flavs: 444mg Epicatechin: 107mg | Matched placebo bar and beverage Total flavs: 19.6mg Epicatechin: 4.7mg | Skeletal muscle (forearm) |
(q) Muniyappa 2008 [69] | Crossover (1 week) | Mild-moderate hypertensives | n = 20 (13 WE, 7 BA) | 51± 6.71 | 60% | 2 weeks | 2*31 g cocoa powder with 150 ml water Total flavs: 902mg Epicatechin: 174mg | 2*31 g matched placebo powder with 150 ml water Total flavs: 28mg Daily epicatechin: 2mg | Skeletal muscle (forearm) |
(o) Decroix 2018b [66] | Crossover (1 week) | Trained cyclists | n = 14 | 30.7 ± 3.1 | 0% | 1 week | 4 capsules Total flavs: 1765mg Epicatechin: 100mg | 4 matched capsules Total flavs: 0mg | Skeletal muscle (leg)/ cerebral |
(r) Shaw 2020 [70] | Crossover (2 weeks) | Trained cyclists | n = 12 | 35 ± 12 | 16.7% | 2 weeks | 120 g (60 g*2) per day 72% dark choc Total flavs: 1788mg Epicatechin: 37.4mg | 120 g (60 g*2) per day non-choc placebo Total flavs: 0mg | Skeletal muscle (leg)/ cerebral |
(s) Sumiyoshi 2020 [71] | Parallel | Healthy | CFs: n = 10 Control: n = 8 | 20–31 | 27.8% | 30 days | 24 g 70% dark chocolate Total flavs: 540mg Epicatechin: 34.8mg | 24.5 g white chocolate Total flavs: ND | Cerebral |