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.

References

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