CLA

Related Terms

ALLMAX Nutrition? CLA95, catalpic acid, CFA-S, CLA by-product, CLA triglyceride oil, CLA-60, CLA-FFA, CLA-free fatty acid (FFA), ClarinolT, ClarinolT A-65, ClarinolT A-80, ClarinolT A-95, ClarinolT G-80, CLA-triacylglycerol, CLN, CLnA, CLNA, conjugated alpha-linolenic acid (CLnA), conjugated diene isomers of linoleic acid, conjugated dienoic derivatives of linoleic acid, conjugated dienoic isomers of linoleic acid, conjugated fatty acids, conjugated linolenic acid, conjugated octadecatrienoic (CLnA) acids, dietary CLA, dietary conjugated linoleic acid, LA, linoleic acid, linolelaidic acid, lipid esterified conjugated linoleic acid, octadecadienoate (18:2), octadecadienoic acids, polyunsaturated fatty acids, positional and geometric isomers of a conjugated diene of linoleic acid, pure conjugated linoleic acid, RA, rumenic acid, ruminant meat, SafflorinT, SafflorinT isomerized safflower oil, safflower oil, sunflower oil, synthetic conjugated linoleic acid mixture, t10c12-CLA, t10,c12-CLA, Tonalin?, Tonalin? CLA, VA, vaccenic acid.
Combination product examples: ProMassT (gamma-linolenic acid and CLA).

Background

Conjugated linoleic acid (CLA) is a fatty acid that is naturally found in beef and dairy products. CLA levels in dairy products may be modified by changing the animals' diets. Most CLA dietary supplements are made from safflower oil. However, CLA is also found in other vegetable oils, including hydrogenated soybean oil.
Scientific interest in CLA began in the 1980s as a result of early evidence suggesting anticancer effects. Since this time, interest in CLA has broadened to areas of weight loss, exercise performance enhancement, and altered body composition. Conjugated linoleic acid is now a wide-selling supplement marketed to reduce obesity and body fat. Conjugated linoleic acid has also been studied for its effects on allergy, asthma, hair loss, heart disease risk, diabetes, high cholesterol, high blood pressure, immune function, and rheumatoid arthritis. The two dominant isomers, or forms, of CLA that have been studied are the cis-9,trans-11 (c9,t11) and the trans-10,cis-12 (t10,c12) forms.

Evidence Table

These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider. GRADE *
These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider. GRADE *


Conjugated linoleic acid (CLA) is a popular supplement marketed to reduce obesity and body fat. While some human evidence suggests that CLA may reduce body fat mass and body weight, results of other studies failed to show these effects. Additional research is needed in this area before firm conclusions can be made.

 B


Conjugated linoleic acid (CLA) is a popular supplement marketed to reduce obesity and body fat. While some human evidence suggests that CLA may reduce body fat mass and body weight, results of other studies failed to show these effects. Additional research is needed in this area before firm conclusions can be made.

 B


Limited research suggests that CLA may reduce sneezing due to birch pollen allergy. Further research is needed.

 C


Limited research suggests that CLA may reduce sneezing due to birch pollen allergy. Further research is needed.

 C


Limited human research showed that CLA may help asthma patients' lung function. Additional research is needed in this area.

 C


Limited human research showed that CLA may help asthma patients' lung function. Additional research is needed in this area.

 C


Although early evidence suggested that CLA had anticancer effects, human studies are needed to investigate the potential anticancer potential of CLA.

 C


Although early evidence suggested that CLA had anticancer effects, human studies are needed to investigate the potential anticancer potential of CLA.

 C


Some, but not all, human studies showed a decrease in blood pressure with CLA treatment. Additional research is needed to investigate the possible cardiovascular effects of CLA.

 C


Some, but not all, human studies showed a decrease in blood pressure with CLA treatment. Additional research is needed to investigate the possible cardiovascular effects of CLA.

 C


Early evidence suggested that CLA might increase insulin sensitivity and reduce blood glucose; however, other studies have suggested that CLA increases insulin resistance in humans. Additional research is needed in this area before a conclusion can be made.

 C


Early evidence suggested that CLA might increase insulin sensitivity and reduce blood glucose; however, other studies have suggested that CLA increases insulin resistance in humans. Additional research is needed in this area before a conclusion can be made.

 C


Results from studies of the effects of CLA on exercise performance are mixed. Additional research is needed in this area before a conclusion can be made.

 C


Results from studies of the effects of CLA on exercise performance are mixed. Additional research is needed in this area before a conclusion can be made.

 C


Preliminary research showed reduced hair loss after CLA treatment. More research is needed in this area.

 C


Preliminary research showed reduced hair loss after CLA treatment. More research is needed in this area.

 C


Early evidence suggests that CLA supplementation may reduce or prevent high blood pressure. Additional research is needed in this area before a conclusion can be made.

 C


Early evidence suggests that CLA supplementation may reduce or prevent high blood pressure. Additional research is needed in this area before a conclusion can be made.

 C


Early evidence suggests that CLA supplementation may have beneficial effects on blood lipids. Additional research is needed in this area before a conclusion can be made.

 C


Early evidence suggests that CLA supplementation may have beneficial effects on blood lipids. Additional research is needed in this area before a conclusion can be made.

 C


Based on human research, CLA may have small, significant effects on some immune markers. Additional research is needed in this area before a conclusion can be made.

 C


Based on human research, CLA may have small, significant effects on some immune markers. Additional research is needed in this area before a conclusion can be made.

 C


Limited research showed that CLA decreased pain, stiffness, and medication needs in patients with rheumatoid arthritis. Additional research is needed.

 C


Limited research showed that CLA decreased pain, stiffness, and medication needs in patients with rheumatoid arthritis. Additional research is needed.

 C
* Key to grades

A: Strong scientific evidence for this use
B: Good scientific evidence for this use
C: Unclear scientific evidence for this use
D: Fair scientific evidence for this use (it may not work)
F: Strong scientific evidence against this use (it likley does not work)
* Key to grades

A: Strong scientific evidence for this use
B: Good scientific evidence for this use
C: Unclear scientific evidence for this use
D: Fair scientific evidence for this use (it may not work)
F: Strong scientific evidence against this use (it likley does not work)

Tradition / Theory

The below uses are based on tradition, scientific theories, or limited research. They often have not been thoroughly tested in humans, and safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider. There may be other proposed uses that are not listed below.

Dosing

Adults (18 years and older)
In humans, the estimated daily intake of CLA is 0.35 grams daily for women and 0.43 grams daily for men, predominantly from milk, milk products, and some meats.
There is no proven safe or effective dose for CLA.
For allergy, two grams of CLA has been taken by mouth daily for 12 weeks.
For asthma, 4.5 grams of CLA has been taken by mouth daily for 12 weeks.
For cardiovascular (heart) disease risk factors, up to four grams of CLA has been taken by mouth daily for up to six months.
For diabetes, doses of CLA of up to 6.4 grams have been taken by mouth daily for up to 16 weeks.
For exercise performance enhancement, doses ranging from 3.9 to 6 grams of CLA have been taken by mouth for 28 days to 12 weeks.
For high cholesterol, 3-3.9 grams of CLA has been taken by mouth daily for 56-63 days. One liter of milk daily naturally enriched with 4.2% of the cis-9,trans-11 (c9,t11) form of CLA has been taken by mouth for eight weeks.
For high blood pressure, 4.7 grams of CLA has been taken by mouth daily for five weeks.
For immune function, 1.7 grams of ClarinolT or 1.6 grams of mixed CLA isomers has been taken by mouth daily for 12 weeks. Two to 3.9 grams of CLA has been taken daily for up to 63 days. Two grams of mixed CLA isomers has been taken by mouth daily for four weeks.
For obesity/weight loss, body fat mass, abdominal diameter, or body weight reduction, up to 6.8 grams of CLA has been taken by mouth for as long as two years. For weight maintenance after weight loss, up to 3.6 grams of CLA has been taken by mouth daily for up to one year. Clinical trials have used up to 4.5 grams of CLA taken by mouth daily for up to 12 weeks or 2.59 grams of CLA in butter taken by mouth for four weeks. Also, 3.4 grams of a purified trans-10,cis-12 (t10,c12) isomer of CLA has been taken by mouth daily for 12 weeks; 1.5 or 3 grams of c9,t11 CLA, 1.5 grams or 3 grams of t10,c12 CLA have been taken by mouth; 80% c9,t11 CLA isomer-enriched (0.59, 1.19, and 2.38 grams daily) or 80% t10,c12 CLA (0.63, 1.26, and 2.52 grams daily) has been taken by mouth for 24 weeks; 500 milliliters of fortified milk containing three grams of CLA has been taken by mouth daily for four months; and 3.2 grams of CLA has been taken by mouth daily (equal amounts of c9,t11 and t10,c12 isomers) for 12 weeks. Milk containing three grams of ClarinolT Lipid Nutrition per serving has been taken by mouth daily for an average of seven months. Three grams of CLA in 500 milliliters of skim milk has been taken by mouth daily for 12 weeks, and 3.76 grams of triacylglycerols (Tonalin 75 TG?) with equal amounts of the c9,t10 and t10,c12 isomers in yogurt has been taken by mouth daily for 14 weeks. One liter of milk naturally enriched with 4.2% of c9,t11 isomer alone has been taken by mouth daily for eight weeks; 0.7 grams of CLA has been taken by mouth daily for four weeks, followed by 1.4 grams of CLA taken by mouth daily for four weeks. CLA (3.4 grams) has been taken by mouth daily for 12 weeks; 2.1 grams of mixed CLA has been taken by mouth for 45 days. According to secondary sources, 2-3 grams of CLA with breakfast, lunch, and dinner was suggested.
For rheumatoid arthritis, five grams of mixed CLA isomers has been taken by mouth daily for 12 weeks.

Safety

The U.S. Food and Drug Administration does not strictly regulate herbs and supplements. There is no guarantee of strength, purity or safety of products, and effects may vary. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy. Consult a healthcare provider immediately if you experience side effects.

Interactions

Interactions with Drugs
Conjugated linoleic acid (CLA) may increase the risk of bleeding when taken with drugs that increase the risk of bleeding. Some examples include aspirin, anticoagulants (blood thinners) such as warfarin (Coumadin?) or heparin, antiplatelet drugs such as clopidogrel (Plavix?), and nonsteroidal anti-inflammatory drugs (NSAIDS) such as ibuprofen (Motrin?, Advil?) or naproxen (Naprosyn?, Aleve?).
CLA may lower blood pressure. Caution is advised when using medications that may also lower blood pressure.
CLA may affect blood cholesterol levels. Caution is advised when using medications that may also affect cholesterol.
CLA may affect blood sugar levels. Caution is advised when using medications that may also affect blood sugar. Patients taking insulin or drugs for diabetes by mouth should be monitored closely by their qualified healthcare professionals, including pharmacists. Medication adjustments may be necessary.
CLA may also interact with antibiotics, antibodies, antidepressants, anticancer drugs, anti-inflammatory drugs, antiobesity drugs, calcium salts, cardiovascular drugs, corticosteroids, drugs for skin conditions, drugs that affect the immune system, drugs that may damage the liver, exercise performance enhancers, fertility agents, gastrointestinal drugs, hematologic agents, hormonal agents, neurologic drugs, osteoporosis drugs, polyethylene glycol (PEG), and surfactants (surface-active agents).

Attribution

This information is based on a systematic review of scientific literature edited and peer-reviewed by contributors to the Natural Standard Research Collaboration (www.naturalstandard.com).

Bibliography

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