Conjugated Linoleic Acid (CLA)
حمض اللينوليك المقترن (CLA)
Weight-loss / everyday active · CAS: n/a (isomer mixture)
A heavily marketed 'fat-burner' that mostly doesn't work - and may quietly do harm. Pooled human studies show little real effect on body weight, and one of its two active forms can actually worsen insulin resistance and add fat to your liver, especially in the overweight people it's sold to. ORIA's call: skip it. If you want a fat that helps your health, ordinary dietary fats and real food beat this.
Why this verdict
A modified fatty acid (a 50:50 mix of two isomers) marketed heavily for fat loss and body recomposition. The honest picture is poor: pooled human RCTs find little or no effect on body weight, and a meta-analysis of CLA+exercise found it does not reduce body weight, improve lipids or boost performance (it may slightly lower body fat). Worse, the t10,c12 isomer present in commercial CLA has documented adverse effects in humans - it can WORSEN insulin resistance and promote liver fat (hepatic steatosis/hyperproinsulinaemia), exactly the metabolic problems of the overweight people it is sold to, and it can lower HDL. Graded CAUTION: minimal proven benefit plus a real, isomer-specific metabolic risk. (Halal-by-plant-source does not override this clinical concern.)
What It Is
A 'fat-loss' fatty acid with little proven weight benefit and a real downside: the t10,c12 isomer can worsen insulin resistance and liver fat in humans. Caution, especially in metabolic syndrome/diabetes.
CLA is a textbook case of a supplement whose marketing got far ahead of its evidence - and then the evidence turned out to point the wrong way. It's a 'conjugated' form of an omega-6 fatty acid, sold in softgels as a stimulant-free fat-burner and body-recomposition aid, usually made from safflower or sunflower oil. The catch is two-fold. First, it largely doesn't work: when researchers pool the human trials, CLA produces little to no change in body weight, and a meta-analysis combining it with exercise found no benefit for weight, blood lipids or athletic performance - at best a small dent in body fat. Second, and more important, commercial CLA is a roughly equal blend of two isomers, and one of them - t10,c12 - has been repeatedly linked in human and animal studies to worsening insulin resistance, raised proinsulin, and fat building up in the liver, along with a drop in protective HDL cholesterol. That's a genuinely awkward profile for a product marketed specifically to overweight people, who are the most likely to already be drifting toward insulin resistance and fatty liver. Being plant-derived (and so halal by source) does not make that clinical concern go away. ORIA's verdict: this is one to skip - minimal upside, a real metabolic downside, and your money is better spent on food.
Evidence & Status
EU Status
Permitted in food supplements.
US · FDA Status
Permitted dietary supplement.
Intake & Safety
Upper limit (UL)
No formal UL; supplement doses typically 3–6 g/day
Interactions
may worsen glycaemic control/insulin resistance (coordinate with diabetes management); may lower HDL; possible additive effects with lipid-altering agents
Third-party testing
useful (identity; isomer ratio matters - c9,t11 vs t10,c12)
Halal Status: Source dependent
CLA is usually made from safflower or sunflower oil (plant) - generally permissible by source. The softgel shell (gelatin vs plant) is the question. NOTE: halal-by-source does not change the clinical caution.
Standard: Active plant-oil-derived — generally permissible by source; softgel shell source-dependent; confirm per MS 1500:2019. Halal source does not override the clinical caution.
Worth Knowing
Also Known As
CLA · conjugated linoleic acid · tonalin · c9 · t11 (rumenic) + t10 · c12 isomers · from safflower/sunflower oil
Primary Source
Evidence, not medical advice. You decide.
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