title: Dose-dependent increases in flow-mediated dilation following acute cocoa ingestion in healthy older adults.
abstract: An inverse relation exists between intake of flavonoid-rich foods, such as cocoa, and cardiovascular-related mortality. Favorable effects of flavonoids on the endothelium may underlie these associations. We performed a randomized, double-blind, placebo-controlled study to test the hypothesis that acute cocoa ingestion dose dependently increases endothelium-dependent vasodilation, as measured by an increase in brachial artery flow-mediated dilation (FMD), in healthy older adults. Measurements were obtained before (preingestion) and after (1- and 2-h postingestion) ingestion of 0 (placebo), 2, 5, 13, and 26 g of cocoa in 23 adults (63 ± 2 yr old, mean ± SE). Changes in brachial artery FMD 1- and 2-h postingestion compared with preingestion were used to determine the effects of cocoa. FMD was unchanged 1 (Δ-0.3 ± 0.2%)- and 2-h (Δ0.1 ± 0.1%) after placebo (0 g cocoa). In contrast, FMD increased both 1-h postingestion (2 g cocoa Δ0.0 ± 0.2%, 5 g cocoa Δ0.8 ± 0.3%, 13 g cocoa Δ1.0 ± 0.3%, and 26 g cocoa Δ1.6 ± 0.3%: P < 0.05 compared with placebo for 5, 13, and 26 g cocoa) and 2-h postingestion (2 g cocoa Δ0.5 ± 0.3%, 5 g cocoa Δ1.0 ± 0.3%, 13 g cocoa Δ1.4 ± 0.2%, and 26 g cocoa Δ2.5 ± 0.4%: P < 0.05 compared with placebo for 5, 13, and 26 g cocoa) on the other study days. A serum marker of cocoa ingestion (total epicatechin) correlated with increased FMD 1- and 2-h postingestion (r = 0.44-0.48; both P < 0.05). Collectively, these results indicate that acute cocoa ingestion dose dependently increases brachial artery FMD in healthy older humans. These responses may help to explain associations between flavonoid intake and cardiovascular-related mortality in humans.
authors: Penn State Heart and Vascular Institute, Pennsylvania State University College of Medicine, Hershey, PA, USA. kmonahan@psu.edu
authors: Kevin D
authors: KD
authors: Monahan
authors: Robert P
authors: RP
authors: Feehan
authors: Allen R
authors: AR
authors: Kunselman
authors: Amy G
authors: AG
authors: Preston
authors: Debra L
authors: DL
authors: Miller
authors: Mary E J
authors: ME
authors: Lott
mesh_terms: D000328:Adult; D001628:Beverages; D001786:Blood Glucose / Q000378:metabolism; D001916:Brachial Artery / Q000187:drug effects / Q000502:physiology; D002099:Cacao; D002392:Catechin / Q000097:blood; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D004435:Eating; D004730:Endothelium, Vascular / Q000187:drug effects / Q000502:physiology; D005260:Female; D005419:Flavonoids / Q000008:administration & dosage; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D014664:Vasodilation / Q000187:drug effects
chemical_list: D001786:Blood Glucose; D005419:Flavonoids; D002392:Catechin