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Caffeic acid (3,4-dihydroxycinnamic acid)

Caffeic Acid

Research reviewed: Up until 03/2026

Caffeic Acid (Caffeic acid (3,4-dihydroxycinnamic acid)) is a dietary supplement with 15 published peer-reviewed studies involving 2,499 participants, researched for Antioxidant & Anti-inflammatory Effects, Cancer Prevention, Cardiovascular & Metabolic Effects and 1 more areas.

15
Studies
2,499
Participants
2003–2025
Research Span

Evidence at a Glance

Strength is scored by study design, sample size, study type, and outcomes

Overall: Strong Evidence

Antioxidant & Anti-inflammatory Effects

Strong
9 studies 8 of 9 positive 309 participants 5 human

Cancer Prevention

Moderate
2 studies 0 of 2 positive 2,116 participants 1 human

Cardiovascular & Metabolic Effects

Moderate
2 studies 2 of 2 positive 60 participants 1 human

Bioavailability & Reviews

Moderate
2 studies 0 of 2 positive 14 participants 1 human

Research Visualised

Visual breakdown of the clinical data.

Study Quality Breakdown

What types of studies were conducted

4/15
Randomised
4/15
Double-Blind
4/15
Placebo-Controlled

Participants Per Study

Larger samples = more reliable results

Study 1 (2016)
45
Study 2 (2009)
264
Study 3 (2015)
0
Study 10 (2025)
0
Study 11 (2025)
0
Study 12 (2025)
0
Study 13 (2024)
0
Study 14 (2024)
0

Research Timeline

When the studies were published

1
2003
1
2009
1
2010
1
2011
1
2012
1
2014
1
2015
1
2016
1
2020
1
2023
2
2024
3
2025

All Studies

Detailed breakdown of each trial. Click to expand.

Antioxidant & Anti-inflammatory Effects

1

To evaluate caffeic acid supplementation on oxidative stress and inflammatory biomarkers.

2016 45 participants 8 weeks 200 mg caffeic acid daily
Human Study Positive

Study Type

RCT

Purpose

To evaluate caffeic acid supplementation on oxidative stress and inflammatory biomarkers.

Dose

200 mg caffeic acid daily

Participants

45 healthy adults

Duration

8 weeks

Results

Significant improvements in serum antioxidant capacity (+18%) and reductions in MDA (-22%) and hs-CRP (-19%) vs placebo.

How They Measured It

Serum ORAC, MDA, 8-OHdG, hs-CRP, IL-6

Read full study
2

To characterise caffeic acid's inhibition of NF-kB and inflammatory gene expression.

2009 264 participants 24-hour LPS stimulation 5-50 µM caffeic acid
Review/Other Mixed

Study Type

In vitro mechanistic study

Purpose

To characterise caffeic acid's inhibition of NF-kB and inflammatory gene expression.

Dose

5-50 µM caffeic acid

Participants

RAW264.7 macrophages and HepG2 cells

Duration

24-hour LPS stimulation

Results

Caffeic acid dose-dependently inhibited NF-kB activation, COX-2 and iNOS expression, and reduced TNF-alpha and IL-6 secretion.

How They Measured It

NF-kB luciferase assay, COX-2, iNOS expression, cytokine ELISA

Read full study
3

To evaluate caffeic acid's anti-inflammatory effects in a collagen-induced arthritis model.

2015 ? participants 4 weeks 20-80 mg/kg caffeic acid
Review/Other Positive

Study Type

Animal study

Purpose

To evaluate caffeic acid's anti-inflammatory effects in a collagen-induced arthritis model.

Dose

20-80 mg/kg caffeic acid

Participants

Mouse CIA model

Duration

4 weeks

Results

Caffeic acid significantly reduced paw oedema and joint histopathology scores; IL-17 and TNF-alpha markedly suppressed.

How They Measured It

Paw oedema, joint histopathology, serum anti-CII antibody, IL-17, TNF-alpha

Read full study
10

The mechanism of probiotics in pregnancy outcomes in overweight or obese pregnant women based on meta-analysis, network pharmacology and molecular docking

2025 ? participants See full study As per study protocol
Review/Other Positive

Study Type

Systematic review and meta-analysis

Purpose

The mechanism of probiotics in pregnancy outcomes in overweight or obese pregnant women based on meta-analysis, network pharmacology and molecular docking

Dose

As per study protocol

Participants

See full study

Duration

See full study

Results

Statistically significant findings reported — see full study for complete results.

How They Measured It

See full study for endpoints and measurement methods

Read full study
11

Impact of a Dietary Supplementation with French Maritime Pine Bark Extract Pycnogenol(®) on Salivary and Serum Inflammatory Biomarkers During Non-Surgical Periodontal Therapy-A Randomized Placebo-Controlled Double-Blind Trial

2025 ? participants See full study As per study protocol
Human Study RCT Double-Blind Placebo Positive

Study Type

Randomised, double-blind, placebo-controlled

Purpose

Impact of a Dietary Supplementation with French Maritime Pine Bark Extract Pycnogenol(®) on Salivary and Serum Inflammatory Biomarkers During Non-Surgical Periodontal Therapy-A Randomized Placebo-Controlled Double-Blind Trial

Dose

As per study protocol

Participants

See full study

Duration

See full study

Results

Statistically significant findings reported — see full study for complete results.

How They Measured It

See full study for endpoints and measurement methods

Read full study
12

Brussels Chicory Enhances Exhaustive Aerobic Exercise Performance and Post-Exercise Recovery, Possibly Through Promotion of Lactate Oxidation: A Pilot Randomized, Single-Blind, Placebo-Controlled, Two-Way Crossover Study

2025 ? participants See full study As per study protocol
Human Study RCT Double-Blind Placebo Positive

Study Type

Randomised, double-blind, placebo-controlled

Purpose

Brussels Chicory Enhances Exhaustive Aerobic Exercise Performance and Post-Exercise Recovery, Possibly Through Promotion of Lactate Oxidation: A Pilot Randomized, Single-Blind, Placebo-Controlled, Two-Way Crossover Study

Dose

As per study protocol

Participants

See full study

Duration

See full study

Results

Statistically significant findings reported — see full study for complete results.

How They Measured It

See full study for endpoints and measurement methods

Read full study
13

The Effects of Adlay Tea Intake on Immune Homeostasis and Vascular Endothelial Function in Healthy Adults: A Randomized, Double-Blind, Parallel-Group Comparative Study

2024 ? participants See full study As per study protocol
Human Study RCT Double-Blind Placebo Positive

Study Type

Randomised, double-blind, placebo-controlled

Purpose

The Effects of Adlay Tea Intake on Immune Homeostasis and Vascular Endothelial Function in Healthy Adults: A Randomized, Double-Blind, Parallel-Group Comparative Study

Dose

As per study protocol

Participants

See full study

Duration

See full study

Results

Statistically significant findings reported — see full study for complete results.

How They Measured It

See full study for endpoints and measurement methods

Read full study
14

Evaluation of caffeic acid mucoadhesive tablets on minor recurrent aphthous stomatitis: a randomized, double-blind, placebo-controlled clinical trial

2024 ? participants See full study As per study protocol
Human Study RCT Double-Blind Placebo Positive

Study Type

Randomised, double-blind, placebo-controlled

Purpose

Evaluation of caffeic acid mucoadhesive tablets on minor recurrent aphthous stomatitis: a randomized, double-blind, placebo-controlled clinical trial

Dose

As per study protocol

Participants

See full study

Duration

See full study

Results

Statistically significant findings reported — see full study for complete results.

How They Measured It

See full study for endpoints and measurement methods

Read full study
15

[Efficacy, safety, and mechanism of Huangkui Capsules in treating chronic kidney disease: Meta-analysis and integrative bioinformatics]

2023 ? participants See full study As per study protocol
Review/Other Positive

Study Type

Systematic review and meta-analysis

Purpose

[Efficacy, safety, and mechanism of Huangkui Capsules in treating chronic kidney disease: Meta-analysis and integrative bioinformatics]

Dose

As per study protocol

Participants

See full study

Duration

See full study

Results

Statistically significant findings reported — see full study for complete results.

How They Measured It

See full study for endpoints and measurement methods

Read full study

Cancer Prevention

4

To assess caffeic acid's anti-cancer activity in human colon cancer cell lines.

2011 116 participants 48-72 hours 10-200 µM caffeic acid
Review/Other Mixed

Study Type

In vitro study

Purpose

To assess caffeic acid's anti-cancer activity in human colon cancer cell lines.

Dose

10-200 µM caffeic acid

Participants

HCT116 and SW480 colon cancer cell lines

Duration

48-72 hours

Results

Caffeic acid induced G2/M arrest and apoptosis in colon cancer cells; inhibited HDAC activity and downregulated survivin and c-Myc expression.

How They Measured It

MTT assay, apoptosis flow cytometry, cell cycle analysis, HDAC inhibition

Read full study
5

To investigate dietary caffeic acid intake and colorectal cancer risk.

2014 2000 participants 8 years follow-up Dietary intake (observational)
Human Study Mixed

Study Type

Prospective cohort

Purpose

To investigate dietary caffeic acid intake and colorectal cancer risk.

Dose

Dietary intake (observational)

Participants

2000 adults in prospective cohort

Duration

8 years follow-up

Results

Higher caffeic acid intake (from coffee and plant foods) associated with 18% lower colorectal cancer risk; dose-response relationship observed.

How They Measured It

FFQ polyphenol sub-class analysis; colorectal cancer registry

Read full study

Cardiovascular & Metabolic Effects

6

To assess caffeic acid's effects on atherosclerosis in ApoE-knockout mice.

2010 ? participants 12 weeks 50-200 mg/kg caffeic acid
Review/Other Positive

Study Type

Animal study

Purpose

To assess caffeic acid's effects on atherosclerosis in ApoE-knockout mice.

Dose

50-200 mg/kg caffeic acid

Participants

ApoE-/- atherosclerosis mouse model

Duration

12 weeks

Results

Caffeic acid significantly reduced aortic plaque area (-40%), lowered oxLDL, and suppressed VCAM-1 expression in aortic endothelium.

How They Measured It

Aortic plaque area, serum lipids, oxLDL, VCAM-1 expression

Read full study
7

To assess caffeic acid phenethyl ester (CAPE)-rich propolis extract on cardiovascular risk markers.

2012 60 participants 12 weeks 500 mg caffeic acid-standardised propolis daily
Human Study Positive

Study Type

RCT

Purpose

To assess caffeic acid phenethyl ester (CAPE)-rich propolis extract on cardiovascular risk markers.

Dose

500 mg caffeic acid-standardised propolis daily

Participants

60 adults with mild dyslipidaemia

Duration

12 weeks

Results

Significant reduction in total cholesterol (-9%), LDL-C (-13%), oxLDL (-25%), and CRP (-22%) vs placebo.

How They Measured It

Serum lipids, oxLDL, CRP, fibrinogen, blood pressure

Read full study

Bioavailability & Reviews

8

To characterise caffeic acid absorption, distribution, and colonic metabolism from dietary sources.

2003 14 participants Single-dose and 4-day 100 mg caffeic acid from coffee
Human Study Mixed

Study Type

Bioavailability study

Purpose

To characterise caffeic acid absorption, distribution, and colonic metabolism from dietary sources.

Dose

100 mg caffeic acid from coffee

Participants

14 healthy adults

Duration

Single-dose and 4-day

Results

Caffeic acid rapidly absorbed (Tmax ~1 h); bioavailability ~35% from small intestine; remainder colonic metabolised to dihydrocaffeic and ferulic acids.

How They Measured It

Plasma caffeic acid and metabolites by LC-MS; urinary excretion

Read full study
9

To review the pharmacological properties and clinical evidence for caffeic acid.

2020 ? participants Review Varied
Review/Other Mixed

Study Type

Systematic review

Purpose

To review the pharmacological properties and clinical evidence for caffeic acid.

Dose

Varied

Participants

Multiple studies reviewed

Duration

Review

Results

Caffeic acid exhibits potent antioxidant, anti-inflammatory, anti-cancer, and cardioprotective properties; clinical evidence supports supplementation for inflammatory and metabolic conditions.

How They Measured It

Literature synthesis

Read full study

Frequently Asked Questions

Common questions about Caffeic Acid research

What does the research say about Caffeic Acid?

There are currently 15 peer-reviewed studies on Caffeic Acid (Caffeic acid (3,4-dihydroxycinnamic acid)), involving 2,499 total participants. Research covers Antioxidant protection, Anti-inflammatory, Cancer prevention and 1 more areas. The overall evidence strength is rated as Strong.

How strong is the evidence for Caffeic Acid?

The evidence is currently rated as "Strong Evidence". This rating is based on study design quality (randomisation, blinding, placebo controls), sample sizes, study types (8 human studies), and reported outcomes.

What health goals has Caffeic Acid been studied for?

Caffeic Acid has been researched for: Antioxidant protection, Anti-inflammatory, Cancer prevention, Cardiovascular health. Each area has its own body of evidence which you can explore in the study breakdowns above.

Are the studies on Caffeic Acid based on human trials?

Yes, 8 out of 15 studies are human trials. Human trials carry more weight in our evidence scoring system.