The never-ending quest for the ultimate body keeps the nutritional supplement business in full swing every year.

Tonalin is one such supplement. It contains conjugated linoleic acid (CLA) and advocates say it can burn fat quickly, while preserving and honing the strength and shape of your muscles.

But while you can find Tonalin online and at most supplement stores, research proving the benefits of CLA and Tonalin is not so readily available.

CLA is a naturally occurring polyunsaturated fatty acid found in animal meat and dairy. In recent years, it’s become a popular dietary supplement.

Fat that your body does not use for energy is absorbed into fat cells with the aid of the enzyme lipoprotein lipase. CLA blocks this enzyme and sends the unabsorbed fat to muscle cells. This theoretically promotes weight loss, increases muscle strength, and improves appearance.

Tonalin claims to be the highest quality CLA supplement available, and it is made from safflower oil extract.

According to a from the Netherlands, CLA is not as beneficial as supplement companies might have you believe. In research conducted on mice and rats, the effects were noticeable but came with the consequence of increasing fat in participants’ livers. This may worsen blood sugar control in people with diabetes and also worsen insulin resistance in those with metabolic syndrome.

Studies conducted on humans have largely been inconclusive, but lean to the fact that CLA does not work well as a fat burner. Tonalin and related supplements should be considered risky until future testing is done.

Vascular Damage

Studies from Italy show that CLA has potential to cause vascular damage in the long term.

A major ruling by the European Food Safety Authority has rejected the notion that CLA and body fat mass reduction are linked, instead calling attention to the limited available data and the negative effects on vascular function.


One from Norway showed that small doses of CLA can cause a minor decrease in body fat mass. However, one major side effect of CLA consumption was extreme fatigue.

Overall, CLA usage should be considered risky. Recent rulings in Europe, as well as most of the science, concludes that there is more testing to be done. It is not safe to assume that Tonalin or any CLA supplements will result in weight loss or muscle definition.