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Cla Matrix Blend

Also known as: CLA, conjugated linoleic acid blend, CLA isomers, cis-9, trans-11 CLA, trans-10, cis-12 CLA, Conjugated Linoleic Acid

Overview

Conjugated Linoleic Acid (CLA) is a naturally occurring fatty acid, a group of positional and geometric isomers of linoleic acid, primarily found in ruminant meat and dairy products. Commercial CLA supplements typically contain a blend of these isomers, most commonly cis-9, trans-11 and trans-10, cis-12. It is widely marketed as a dietary supplement for its purported benefits in improving body composition, aiding weight loss, and supporting metabolic health. While numerous randomized controlled trials and meta-analyses have investigated CLA, findings regarding its efficacy and safety remain mixed. The evidence quality ranges from low to moderate certainty, with observed heterogeneity in study designs, dosages, isomer compositions, and target populations. Despite its popularity, the clinical significance of its effects is often debated.

Benefits

CLA supplementation has been shown to result in a small but statistically significant reduction in body weight (approximately 0.35 to 0.72 kg) and body fat percentage (around 1.3%) in adults, including those at risk of cardiovascular disease. Modest reductions in BMI (around 0.22 kg/m²) have also been observed. These effects are primarily seen in general adult populations and those with cardiovascular risk factors. However, the magnitude of these anthropometric improvements is generally considered small and may not be clinically meaningful for significant weight loss. Importantly, CLA has not consistently demonstrated beneficial effects on lipid profiles or blood pressure. Some research indicates that CLA may increase markers of oxidative stress, such as 8-isoprostanes, suggesting potential pro-oxidant effects, which could be a concern for long-term use. Most studies are short-to-medium term, and long-term benefits are not well characterized.

How it works

CLA is believed to influence body composition by modulating lipid metabolism. Its primary mechanisms include increasing fat oxidation and reducing lipogenesis (fat storage). CLA may interact with peroxisome proliferator-activated receptors (PPARs), which are nuclear receptor proteins that play a crucial role in regulating genes involved in fat metabolism, energy homeostasis, and inflammation. Different CLA isomers may have varying biological activities. Some isomers are also thought to induce oxidative stress, potentially affecting cellular signaling and metabolic pathways. The bioavailability of CLA varies depending on the specific isomer and the formulation (e.g., free fatty acid vs. triglyceride forms), with absorption generally enhanced when taken with fat-containing meals.

Side effects

CLA is generally well tolerated at doses used in clinical trials. The most common side effects, affecting more than 5% of users, are mild gastrointestinal symptoms such as diarrhea or upset stomach. Less common side effects (1-5%) include a possible increase in oxidative stress markers, which, while not immediately severe, could have long-term implications for cellular health. Rare side effects (less than 1%) are not consistently reported. Limited data exist regarding drug interactions, but caution is advised when combining CLA with lipid-lowering or antioxidant medications due to potential interference. Contraindications are not well established, but individuals with conditions related to oxidative stress should exercise caution. The safety profile in special populations such as pregnant or lactating women, children, or individuals with severe chronic diseases is not well studied, and its use in these groups is not recommended without medical supervision.

Dosage

Studies typically use CLA blends at a dosage range of 3 to 6 grams per day. An optimal dosage of approximately 3.4 to 6 grams daily appears common in randomized controlled trials that have shown modest benefits in body composition. Up to 6 grams daily is generally considered safe for short-term use, but long-term safety data beyond this dose or duration are limited. CLA is usually administered with meals to improve absorption, as fat-containing meals enhance its bioavailability. Most supplements contain a mixture of cis-9, trans-11 and trans-10, cis-12 isomers, and the specific ratio of these isomers can influence outcomes. No specific cofactors are required for CLA absorption or efficacy, but an individual's antioxidant status may influence its safety profile, particularly concerning potential oxidative stress markers.

FAQs

Is CLA effective for weight loss?

CLA produces small, statistically significant reductions in body weight and fat, but these effects are modest and unlikely to replace comprehensive lifestyle interventions for significant weight loss.

Is CLA safe to take?

Generally safe at studied doses, but it may increase oxidative stress markers. Long-term safety, especially regarding these markers, is not fully clear and requires more research.

When is the best time to take CLA?

It is recommended to take CLA with meals to enhance its absorption and bioavailability, as fat-containing meals improve its uptake.

How long does it take to see effects from CLA?

Benefits from CLA supplementation, primarily modest changes in body composition, are typically observed within weeks to a few months of consistent use.

Does CLA improve cholesterol levels?

No, current research indicates that CLA does not consistently improve lipid profiles, including cholesterol levels, and may even increase triglycerides in some cases.

Research Sources

https://publish.kne-publishing.com/index.php/JNFS/article/download/14852/13944 – This systematic review and meta-analysis of 12 RCTs found that CLA supplementation significantly increased the oxidative stress marker 8-iso-PGF2α (SMD=1.48). The study highlights potential pro-oxidant effects of CLA, noting heterogeneity in CLA forms, doses, and isomers across the included trials.
https://pubmed.ncbi.nlm.nih.gov/39439191/ – This high-quality systematic review and meta-analysis of 14 RCTs involving adults at risk of cardiovascular disease reported small but significant reductions in body weight (-0.72 kg), BMI, and body fat percentage with CLA. However, it found no significant effect on lipid profiles or blood pressure, questioning the clinical relevance of the small effect sizes.
https://pubmed.ncbi.nlm.nih.gov/37671495/ – A comprehensive meta-analysis of 70 RCTs with 4159 participants confirmed that CLA significantly reduced body mass (WMD -0.35 kg), BMI, waist circumference, fat mass, and body fat percentage in adults. Despite rigorous methods, the study noted high heterogeneity and variable study quality among the included trials, confirming modest anthropometric benefits.
https://www.frontiersin.org/journals/nutrition/articles/10.3389/fnut.2024.1336889/full – This systematic review and meta-analysis of 35 RCTs specifically investigating CLA's impact on lipid profiles concluded that CLA did not improve lipid profiles and might even increase triglycerides. The study noted low certainty evidence and heterogeneity in populations and doses, suggesting no consistent benefit for lipid health.