tuneTypical Dose
3.0-3.4 g/day total CLA, split with meals
Supplement
Conjugated Linoleic Acid
Conjugated Linoleic Acid
Evidence TierCWADA NOT PROHIBITED
watchEffect Window
Start with 2-12 weeks for most practical outcomes.
check_circleCompliance
WADA NOT PROHIBITED
Overview
Clinical Summary
Conjugated Linoleic Acid is a group of linoleic acid isomers studied for body composition and lipid metabolism. It is used for modest fat mass reduction goals.
Meta analyses show small reductions in body fat in some populations, with limited effects on weight overall. Effects on lipids and insulin sensitivity are inconsistent, and some studies report worsened glucose control in susceptible groups. Minority benefits include reduced oxidative stress markers. Gastrointestinal side effects are common.
Human outcome confidence is limited. Plausible mechanisms appear preparation-specific and are not consistently replicated in controlled trials.
Outcomes
What This Is Expected To Influence
Primary Outcomes
- adjunct symptom support
- tolerability improvement
Secondary Outcomes
- function score trend
- subjective wellbeing
Safety
Contraindications and Interactions
Contraindications
- Pregnancy/lactation
- Severe liver or kidney disease
- Medication interactions
Side effects
- GI discomfort
- Drowsiness/sedation (agent-dependent)
- Headache
Interactions
- Drug absorption interactions
- Sedatives/CNS-active agents
- Anticoagulants
Avoid if
- Unknown source quality
- Unstable medical conditions
- Complex medication stack
Evidence
Study-level References
conjugated-linoleic-acid-SRC-001Secondary evidence synthesis
Sourceopen_in_newSRC-002 synthesis anchored to PMID: 39150026, summarizing small average fat-mass effects and inconsistent metabolic findings.
Population: Adult human cohorts; mixed conditions and comparators
Dose protocol: Common protocols use about 3-4 g/day total CLA in divided doses
Key findings: Mixed to weak, often context-specific
Notes: Strong heterogeneity in dosing, endpoints, and outcome quality
Paper content
No consistent pooled superiority across all outcomes
conjugated-linoleic-acid-SRC-002Secondary evidence synthesis
Sourceopen_in_newSRC-002 synthesis anchored to PMID: 39150026, summarizing small average fat-mass effects and inconsistent metabolic findings.
Population: Adult human cohorts; mixed conditions and comparators
Dose protocol: Variable
Key findings: No consistent pooled superiority across all outcomes
Notes: Inconsistent methods and selective reporting in available literature
Paper content
No consistent pooled superiority across all outcomes
conjugated-linoleic-acid-SRC-003Double-blind, randomized, placebo-controlled trial.
Sourceopen_in_newJia K, She Y, He Y, He J, et al. Conjugated linoleic acid supplementation suppresses the de novo lipogenesis in adults with high body fat. Mol Nutr Food Res. 2025;69(23-24):e70306. doi:10.1002/mnfr.70306. PMID:41169023.
Population: Adults with elevated body fat percentage.
Dose protocol: 12-week CLA supplementation versus placebo in 65 adults with high body fat.
Key findings: CLA suppressed de novo lipogenesis markers (decreased erythrocyte C16:1n7 and C18:1n9, increased C18:3n3) with correlated improvements in plasma and liver lipid profiles.
Notes: Provides mechanistic support for the modest fat-reduction signal seen in CLA meta-analyses.
Paper content
This double-blind RCT randomized 65 adults with elevated body fat to CLA or placebo for 12 weeks. CLA supplementation decreased erythrocyte C16:1n7 and C18:1n9 (markers of desaturase activity related to de novo lipogenesis) while increasing C18:3n3. These fatty acid shifts correlated with improvements in plasma and liver lipid profiles, suggesting that CLA suppresses de novo lipogenesis in humans with high body fat. The study provides a mechanistic link between CLA intake and lipid metabolism changes, supporting the small body composition effects seen in meta-analyses.