Tonalin is a brand name for for CLA (conjugated linoleic acid). Many studies show that CLA helps preserve muscle while reducing body fat.
One study concluded that “CLA supplementation for 4 weeks in obese men with the metabolic syndrome may decrease abdominal fat, without concomitant effects on overall obesity or other cardiovascular risk factors.” ((http://www.nature.com/ijo/journal/v25/n8/abs/0801659a.html;jsessionid=BEEC4EB0FD89DF864FEF344A7D7D831F))
Another study ((Conjugated Linoleic Acid Reduces Body Fat in Healthy Exercising Humans; Thom, Wadstein, and Gudmundsen. 2001)) found that the subjects taking CLA decreased their body fat from 21.3% to 17%. That is a significant amount. They only lost a small amount of weight, but remember, CLA is designed to help you maintain (or increase) your muscle while you lose the body fat. Muscle weighs more than fat.
CLA is one of the few ingredients that actually has been studied a great deal. The vast majority of which is quite supportive of its claims to help in weight loss. Big thumbs up for CLA and the branded version of it, Tonalin.