CLA, or conjugated linoleic acid, is a type of trans fatty acid found in high concentrations in beef and dairy products. But don’t get scared away by the mention of trans fat, because CLA is actually beneficial and linked to reduced risk of cardiovascular disease and long-term weight management. CLA, which is a mixture of the different types of linoleic acid that occur in nature, can also be taken as a dietary supplement. Consult your doctor before taking supplements that contain high amounts of CLA.
Conjugated linoleic acids are a family of at least 28 isomers or subtypes of linoleic acid. Linoleic acid, often abbreviated as LA, is an unsaturated omega-6 fatty acid. It’s classified as an essential fatty acid because your body cannot make it from other sources. Consequently, you must obtain LA or CLA from dietary sources or via supplementation. The richest sources of CLA are grass-fed beef and raw or unpasteurized dairy products that come from grass-fed cattle. Levels of CLA are up to five times higher in grass-fed cows than those fed grains such as corn. A lot of research on the health benefits of CLA has been conducted, although most of it has been on animals.
CLA consumption reduces body fat while preserving muscle tissue, which essentially increases lean body mass and metabolic rates. Results are best in those who combine exercise with dietary intake of CLA. The improved muscle-to-fat ratio is related to improved insulin sensitivity, which allows fats and glucose to be attracted to muscle cells and fat cells more equally. More fat and glucose is burned as energy instead of being stored as fatty adipose tissue. The affect of CLA on insulin, which mimics that of diabetic drugs, may be good news for Type 2 diabetics who have trouble with reduced insulin sensitivity. Researchers need to do more testing on diabetics before they can make specific recommendations for CLA.
Reduced Risk of Cancer
CLA consumption may slow cancer cell formation and progression, especially with breast, colorectal, prostate, lung, skin and stomach cancers. CLA is the only fatty compound that inhibits various stages of carcinogenesis in animals, and it does so by increasing absorption of fat-soluble vitamins A and D as well as exerting effects on chemicals that regulate cellular function. Animals fed CLA show a reduced incidence and size of benign and malignant tumors. CLA also seems to improve immune system response by reducing chemicals that tend to suppress immune function, which has implications for cancer and many other diseases. The reduction in these chemicals, such as leukotrienes and prostaglandins, also reduces the inflammatory reaction in your body, which may have positive implications for those suffering from arthritis and allergies.
Reduced Risk of Cardiovascular Disease
CLA's ability to prevent the storage of fat may also help reduce the risk of clogged arteries or atherosclerosis. Atherosclerosis is the buildup of fatty plaques in arteries, which is a primary cause of heart attacks and high blood pressure. CLA prevents atherosclerosis by reducing “bad” LDL cholesterol in the blood and increasing “good” HDL cholesterol. CLA may also help prevent cardiovascular disease by acting as an antioxidant and eliminating artery-damaging free radicals.
- Contemporary Nutrition: Functional Approach; Gordon M. Wardlaw et al.
- PDR for Nutritional Supplements; Sheldon Hendler and David Rorvik
Sirah Dubois is currently a PhD student in food science after having completed her master's degree in nutrition at the University of Alberta. She has worked in private practice as a dietitian in Edmonton, Canada and her nutrition-related articles have appeared in The Edmonton Journal newspaper.