This is, in essence, a question about economics. It is a question that asks us whether a given incentive will be enough to change human behavior.
All other things being equal, providing a monetary incentive should increase the likelihood that workers at a given organization will do things that will help them to lose weight. The laws of economics tell us that people are more likely to do things when they are paid to do them than when they get no tangible reward. Therefore, giving people money should lead them to behave in ways that would make them lose weight.
However, this program would have to be set up correctly. In particular, it would be very important to give people information about how to lose weight. It would not be enough to simply provide money if individuals lost weight. The reason for this is that the monetary reward might not outweigh the time it would take to figure out what to do in order to lose weight or the emotional frustration that would occur if the person could not lose weight.
Monetary rewards will make people more likely to lose weight. Doing so provides people with a benefit that they obtain by losing weight. However, the laws of economics tell us that it is also important to reduce the “costs” of losing weight. It is important to make it easier for people to know what to do so that the costs (in time and emotional commitment) will not be higher than the monetary benefit.