6 Health Benefits of CLA Supplements (Research Backed)

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Conjugated linoleic acids (C 18:2) are a group of naturally occurring polyunsaturated fatty acids found in the fats of ruminants, including cow, goats, and sheep.

Studies showed that it could modify body composition, glycemic profile, and immune function.

Therefore, CLA rich foods are gaining popularity as functional foods and a weight loss supplement. [1][2]

Health Benefits of CLA Supplements

The key benefit of CLA supplements includes reducing body fat mass in obese or overweight individuals. It may modulate serum lipid markers, increase exercise performance, and reduce the proliferation of tumors. Little studies showed that it might enhance immune function and reduce symptoms associated with irritable bowel syndrome.

1. CLA supplements reduced body fat mass in obese adults

Long term CLA supplementation reduced body fat mass in obese adults.[3] [4] [5]

A double-blind study involving obese volunteers showed that consumption of CLAs (3.4g and 6.8g) for 12 weeks showed a reduction in body fat.[6]

CLA-free fatty acid and CLA-triacylglycerol consumption for a year reduced mean body fat mass in healthy overweight volunteers.[7]

It decreased lean body mass in obese individuals.[8]

One study showed that CLA supplementation reduced body fat mass mostly in the legs and in the women.[9]

Another study showed that it prevented weight gain during the holiday and decreased negative emotions.[10]

What it means: Several studies showed that long term supplementation of CLAs reduced body fat mass in obese or overweight individuals modestly. Additional studies are required to study the molecular mechanisms involved in the prolonged use of CLAs.

2. CLA supplements may modulate serum lipid markers

Studies showed that CLA supplements might improve lipid metabolism by modulating serum lipid markers.[11] [12] [13]

A study showed that mixed isomer CLA supplementation (3.9g/day) reduced total plasma cholesterol and LDL cholesterol levels in exercising nonobese individuals. [14]

A study showed that CLA supplementation increased the total to HDL cholesterol ratio in healthy individuals.[15]

80:20 CLA isomer blend reduced plasma VLDL and triacylglycerol concentration.[16]

CLA supplementation before and after six weeks of aerobic training lowered blood triacylglycerol levels.[17]

What it means: CLA supplementation may modulate serum lipid markers. It may decrease plasma triacylglycerol, LDL cholesterol, and total cholesterol levels. More studies are required to examine the efficacy of lipid-modifying properties of CLA supplements.

3. CLA supplements may increase exercise performance

CLA supplementation may increase strength and lean muscle mass following resistance training.

A combination of CLA supplements with creatine monohydrate enhanced strength gains, up arrow fat-free mass, and down arrow total body fat in older adults.[18]

Another study showed that a combination of CLA, creatine, and whey protein increased strength and lean tissue mass during resistance strength training.[19]

CLA supplementation during resistance training lessened catabolic effects on muscle protein, 3-methylhistidine.[20]

It increased testosterone production following resistance exercise.[21]

However, in one study, CLA supplementation did not improve aerobic training-induced fatigue and muscle endurance.[22]

What it means: Few studies showed that CLA supplementation during and after resistance training might increase strength and lean muscle mass. More randomized controlled studies are required to investigate the benefits of taking CLA supplements during exercise.

health benefits of CLA Supplements

4. Anticancer properties of CLA supplements

CLA supplements may reduce tumor proliferation, lower resistance to cancer treatment, and induce apoptosis of cancer cells.

A study showed that 7.5g/day of CLA supplementation showed a reduction in the proliferation index of breast tumors.[23]

In vitro study showed that CLA-gemcitabine conjugate had antitumor activity against MCF-7 breast tumor cell line.[24]

CLA supplementation reduced invasion of the tumor and lowered resistance to cancer treatment in rectal cancer patients by lowering MMP-9 and MMP-2 levels.[25]

Also, in another study, CLA supplementation induced the apoptotic pathway in colorectal cancer cells.[26]

What it means: Limited studies showed that CLA supplementation might inhibit tumor proliferation, reduce the resistance to anticancer treatments, and induce apoptosis. Future studies will determine the efficacy of anticancer properties of CLA supplements.

5. CLA supplements may reduce symptoms associated with inflammatory bowel diseases

CLA supplements may reduce symptoms of inflammatory bowel disease by activating the PPARγ pathway and reducing inflammatory cytokines.[27]

Oral CLA supplementation suppressed the production of proinflammatory cytokines and improved the quality of life in mild to moderate Crohn’s disease patients.[28]

An animal study showed that CLA supplementation enhanced PPARγ and reduced inflammatory lesion development.[29] [30]

What it means: Few studies reported that CLA supplementation reduced the inflammation associated with irritable bowel syndrome and thereby improved the quality of life. Further studies are required to verify the anti-inflammatory properties of CLA supplements.

6. CLA supplements may enhance immune function

Some studies showed that CLA supplements might modulate the immune function and prevent immune-induced allergic reactions. [31]

In a study, CLA supplements increased PHA-induced lymphocyte proliferation in healthy volunteers.[32]

A study showed that CLA 50:50 fatty acid consumption initiated antibody production to hepatitis B vaccination in healthy male subjects.[33]

1.0% CLA diet increased levels of immunoglobin A, G, and M in animals mitigating food-induced allergic reaction. It decreased IgE levels.[34]

It also reduced delayed-type hypersensitivity response.[35]

What it means: Few studies indicated that CLA supplements might have immunomodulatory properties. It may increase the production of antibodies, reduce delayed-type hypersensitivity response, and lower food allergic reactions. Future studies will help in understanding the mechanisms by which CLA supplements increase immune function.


Possible Side effects of CLA Supplements

CLA supplements are likely safe when taken in recommended amounts.

It may cause stomach upset, nausea, fatigue, backache, and increased risk of bleeding when taken in excess amounts. Rarely, it may cause liver toxicity.


There is no reliable information about the safety of CLA supplements during pregnancy and breastfeeding, therefore avoid taking CLA during these times.

Avoid CLA supplements if having bleeding disorders, diabetes, and metabolic syndrome. It is recommended to stop taking CLAs at least two weeks before a scheduled surgery.

Drug Interactions with CLA Supplements

At present, there is no well-documented interaction of CLA supplements with other drugs.[36] [37]

Dosage of CLA Supplements

There is no optimal recommended dose of CLA supplements.

The different clinical studies used CLA supplements in the range of 3200-6400mg/day. It should be taken with meals.[38]


What is the role of CLA supplements on insulin resistance?

There appears to be both sensitization and resistance associated with CLA supplementation. In a double-blind, placebo-controlled study involving metabolic syndrome patients, t10c12 CLA supplement isomer increased oxidative stress and insulin resistance. [39] [40] [41]
However, in another study, CLA supplementation reduced fasting blood glucose levels.[42] [43] Therefore, long term studies are required to evaluate its safety in improving insulin resistance.


Conjugated linoleic acids (CLA) are polyunsaturated fatty acids found in ruminants. It is gaining popularity as a weight-loss supplement and may have a role in reducing body fat mass and modulating serum lipid markers.

However, only a few studies have examined the effects of CLA in humans, and many questions concerning the safety and efficacy of consuming CLA supplements are yet to be answered. Future investigations will provide conclusive evidence about the pros and reliability of taking a CLA supplement.