First off, this has nothing even remotely related to weight loss surgery. I found this research interesting so I thought I would post a link.
Two groups of Native Americans, the Flatheads of Montana and the Blackfoot of Alberta, used sweetgrass as an insect repellent. They did so by burning the grass and allowing the smoke to saturate their clothing or by placing sachets (scented bags) of sweetgrass in their clothing. A group of scientist tested the effectiveness of essential oils of sweetgrass in a side by side comparison with DEET in the effectiveness to repel mosquitoes. They found that they were equally effective. The results were published recently in the Journal of Agricultural and Food Chemistry.
http://acsh.org/news/2016/11/01/sweetgrass-deet-traditional-native-american-herbal-remedy-acts-mosquito-repellent
So why might this be of importance. The answer is Zika virus which is spread by bites from mosquito, the type that is found in warm climates such as Florida along with other pathways (such as sexual transmission with infected individuals). Sweetgrass may provide an alternate to DEET in repelling mosquitos.