Feruchemical Weight Loss
I was thinking on my to class about Feruchemy, and when would be good times to store different things. When I got to thinking about storing energy, I realized that you may be able to store stuff you're not currently eating. This would mean that you could store fat, and dehydrate yourself at will. I'm not sure what benefits being dehydrated would give you, other than maybe making a more convincing disguise in some cases, but the first one is obviously useful. You could add some chub to disguise yourself as a rich person, and take off a lot for a poor person. Or, you could just lose weight. Either way, it would be really useful, if it is possible.
I've never heard of this method. Well, I guess it's not really popular, because there are chances that it can be risky for health.
The whole idea of Feruchemy reminds me a bit of how some people actually try to adjust their body composition with different strategies for fitness or even sports. I remember hearing about people who use things like Steroids Canada to build muscle or cut fat, depending on their goals. But in this case, steroids can actually help.
I think the idea of changing things like hydration or adding a bit of bulk to make yourself look different could be useful in the fitness world too.