CLA (Conjugated Linoleic Acid)
Also known as: Conjugated Linoleic Acid, c9,t11-CLA, t10,c12-CLA, rumenic acid
Effective Dosage
No established dose from provided studies
What the Science Says
CLA is a naturally occurring fatty acid found in dairy products and meat from ruminant animals like cows. It exists as a mix of different molecular forms, two of which (c9,t11 and t10,c12) are considered biologically active. Animal studies suggest it may reduce fat mass and affect lipid metabolism, but reviews of human clinical trials have not confirmed meaningful fat loss or body composition benefits in people.
What It Doesn't Do
Won't reliably burn fat in humans — animal results don't translate. No solid proof it builds muscle or improves body composition. Not a proven weight loss supplement despite heavy marketing claims. Don't expect cardiovascular benefits; evidence is mixed and inconclusive.
Evidence-Based Benefits
In adults with high body fat, 12-week CLA supplementation suppressed de novo lipogenesis (DNL) activity, reducing erythrocyte C16:1n7 and C18:1n9 fatty acids while increasing C18:3n3, with associated changes in triglycerides and LDL-C (PMID 41169023). In cattle, CLA supplementation — particularly the t10,c12 isomer — has been shown to reduce subcutaneous fat and improve intramuscular fat content, with effects on energy balance and milk yield, though results are inconsistent across studies (PMID 41751012).
Weak EvidenceEffective at: No established dose from provided human studies
Source: auto-research
Absorption & Bioavailability
Unknown — the provided studies do not report human absorption or bioavailability data
Red Flags to Watch For
- The t10,c12 isomer found in most supplements may worsen insulin resistance and raise blood lipids — a potential metabolic harm
- CLA supplementation in lactating women was linked to lower fat content in breast milk, raising concerns for nursing mothers
- Maternal CLA supplementation in animal studies altered offspring metabolism, suggesting possible developmental effects
- 13 randomized controlled trials reviewed found no meaningful fat loss benefit in humans, yet products are heavily marketed for weight loss
- Most compelling research is from rodent studies, which frequently do not translate to human outcomes
Research Sources
- PubMed
- NIH DSLD
This information is for educational purposes only and is not medical advice. Always consult a healthcare professional before starting any supplement regimen. Last updated: 2026-04-06