Is it safe to apply body slimming gel if I am breastfeeding? Would like to target my arms, tummy and thighs. Thanks!

Some people say that it does get into the body system but then there are those slimming centers that apply gel on ur body for their treatment - to help women lose their pregnancy weight. I did w Marie France and their cream was ok - they been using it for many years and it's topical application. So i guess if ur cream is the safe kind (not from some online shop/craze - got a lot of fakes) but sold in a proper store in SG (so that it is regulated) then should be ok