Weight loss spells, mantras, chants and the like are all good self motivators for you to achieve your goal. They in themselves will notnot magically make you thinner overnight ( as Eiskora already told you) , but they may enable you to eat one less spoon of that pound cake that your mom made. They in themselves will not instantly transform you the next day (as many people in this community think and believe) to two dress sizes lower, but they may remind you to take an extra glass of water before the meal starts. They will not make you into the prince charming after a day, but they may add to your confidence.
Weight loss spells, and others like that aren't shams in itself but perhaps a reminder that allows you to be the better person you can always become. These spells are self motivating guides, constant reminders that we tell ourselves to achieve what we want to happen. People might get disappointed and think that its not what they thought it was, weight loss spells may not be considered really as a weight loss method but it does have a great influence on how we think. And oftentimes, the effectiveness of any diet program will start and stem out from our motivation, our state of mind. Hope I made my point.