Effect of dark chocolate/ cocoa consumption on oxidative stress and inflammation in adults: A GRADE-assessed systematic review and dose-response meta-analysis of controlled trials.
Complement Ther Med
; 84: 103061, 2024 Sep.
Article
in En
| MEDLINE
| ID: mdl-38925412
ABSTRACT
BACKGROUND:
Oxidative stress and inflammation play critical roles in the pathogenesis of many chronic diseases. Dark chocolate (DC)/cocoa, as a rich source of polyphenols like flavonoids, has anti-inflammatory and antioxidant properties that may confer health benefits, but findings in this context are inconsistent.OBJECTIVE:
This systematic review and dose-response meta-analysis aimed to provide a comprehensive overview of the controlled trials (CTs) that have examined the effects of DC/cocoa on oxidative stress and inflammation biomarkers in adults. SEARCHMETHODS:
Databases including PubMed, Web of Science, and Scopus, were searched for relevant studies through April 2024. SELECTION CRITERIA Studies assessed C-reactive protein (CRP), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), malondialdehyde (MDA), nitric oxide (NO), P-selectin, E-selectin and thiobarbituric acid reactive substances (TBARS) in adults were included. DATAANALYSIS:
Based on the random-effects model, we calculated WMDs, SMDs and 95 % confidence intervals (CIs). Sensitivity, sub-group, meta-regression and dose-response analyses were also conducted.RESULTS:
Thirty-three eligible CTs with 1379 participants were included. All studies reported the intervention types (cocoa powder, beverages and chocolate bars) and dosage. However, sixteen studies didn't do/report testing for purity and potency by independent groups. Also, none of the studies mentioned the risk of contamination with heavy metals. Another limitation was the lack of blinding assessment in studies. DC/cocoa significantly reduced MDA (SMD -0.69, 95 %CI -1.17, -0.2, p = 0.005) and increased NO levels (SMD 2.43, 95 %CI 1.11,3.75, p < 0.001); However, it has no significant effects on the other outcomes. Greater anti-inflammatory effects occurred at higher flavonoid doses (>450 mg/day) and for shorter durations (≤4 weeks) in the non-healthy participants. Non-linear dose-response relationships between cocoa dosage and CRP level and also between flavonoid dosage and IL-6 level were observed. Based on the GRADE evaluation, just CRP and MDA results were considered as high certainty evidence and the other outcomes results were categorized as very low to moderate certainty.CONCLUSIONS:
DC/cocoa may improve systemic oxidative status and inflammation in adults. However, further studies should be performed to determine its benefits.Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Cacao
/
Oxidative Stress
/
Chocolate
/
Inflammation
Limits:
Adult
/
Humans
Language:
En
Journal:
Complement Ther Med
Journal subject:
TERAPIAS COMPLEMENTARES
Year:
2024
Document type:
Article
Affiliation country:
Iran