Health Guide

Conjugated linoleic acid (CLA)

What is it?

Conjugated linoleic acid (CLA) is a supplement used for weight loss. CLA has not been proven to work for weight loss in people. Talk to your doctor before taking CLA. CLA has not worked to lower cholesterol in studies in people. CLA has been studied as an antioxidant, for certain types of cancer, and to prevent food allergies in animals and in the laboratory but its effect in people for these conditions is not known.

Other names for conjugated linoleic acid include: CLA.

Ask your doctor, nurse, or pharmacist if you need more information about this medicine or if any information in this leaflet concerns you.

Before Using:

Tell your doctor if you

  • are taking medicine or are allergic to any medicine (prescription or over-the-counter (OTC) or dietary supplement)
  • are pregnant or plan to become pregnant while using this medicine
  • are breastfeeding
  • have any other health problems, such as high blood pressure or heart or blood vessel disease


Talk with your caregiver about how much conjugated linoleic acid you should take. The amount depends on the strength of the medicine and the reason you are taking conjugated linoleic acid. If you are using this medicine without instructions from your caregiver, follow the directions on the medicine bottle. Do not take more medicine or take it more often than the directions tell you to.

To store this medicine:

Keep all medicine locked up and away from children. Store medicine away from heat and direct light. Do not store your medicine in the bathroom, near the kitchen sink, or in other damp places. Heat or moisture may cause the medicine to break down and not work the way it should work. Throw away medicine that is out of date or that you do not need. Never share your medicine with others.

Drug and Food Interactions: Do not take conjugated linoleic acid without talking to your doctor first if you are taking:

  • Orlistat (Xenical(R)) (8)


  • Before taking linoleic acid, tell your doctor if you are pregnant or breastfeeding.
  • If you have high risk of heart problems or already have heart problems, talk to your doctor before taking conjugated linoleic acid (5).
  • When mothers had higher levels of conjugated linoleic acid and lower levels of other essential fatty acids (omega 3), children had a greater incidence of atopic (allergy) disease (9).
  • Diets high in conjugated linoleic acid can lead to allergic inflammation (red, itchy, swelling) in children (9).

Side Effects:

Call your doctor right away if you have any of these side effects:

  • Allergic reaction: Itching or hives, swelling in your face or hand, swelling or tingling in your mouth or throat, chest tightness, trouble breathing, or rash.

Other Side Effects:

You may have the following side effects, but this medicine may also cause other side effects. Tell your doctor if you have side effects that you think are caused by this medicine.

  • Upset stomach, burping, constipation, or vomiting (4)
  • Unusual bleeding (tell your doctor about any signs of bleeding) (6,7)


1. Mougios V, Matsakas A, Petridou A et al: Effect of supplementation with conjugated linoleic acid on human serum lipids and body fat. J Nutr Bio 2001; 12:585-594.

2. Conjugated linoleic acid (CLA) reduced abdominal adipose tissue in obese middle-aged men with signs of the metabolic syndrome: a randomized controlled trial. Int J Obes Relat Metab Disord 2001; 25(8):1129-1135.

3. Smedman A & Vessby B: Conjugated linoleic acid supplementation in humans-metabolic effects. Lipids 2001; 36(8):773-780.

4. Blankson H, Stakkestad J, Fagertum H et al: Conjugated linoleic acid reduces body fat mass in overweight and obese humans. J Nutr 2000; 130(12):2943-2948.

5. Basu S, Riserus U, Turpeinen A et al: Conjugated linoleic acid induces lipid peroxidation in men with abdominal obesity. Clin Sci (Lond) 2000; 99(6):511-516.

6. Benito P, Nelson G, Kelley D et al: The effect of conjugated linoleic acid on platelet function, platelet fatty acid composition, and blood coagulation in humans. Lipids 2001a; 36(3):221-227.

7. Truitt A, McNeill G & Vanderhoek J: Antiplatelet effects of conjugated linoleic acid isomers. Biochim Biophys Acta 1999; 1438(2):239-246.

8. Vidgren H, Agren J, Valve R et al: The effect of orlistat on the fatty acid composition of serum lipid fractions in obese subjects. Clin Pharmacol Ther 1999; 66:315-22.

9. Kankaanpaa P, Sutas Y, Salminen S et al: Dietary fatty acids and allergy. Ann Med 1999; 31(4):282-287.

Last Updated: 7/4/2018
The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites.

All rights reserved