If you want to change the way you eat or attempt to change the way you look, go ahead. Everyone can eat however they want to, at any time. Just try to be aware that.. 
January is often the worst time of the year for people with eating disorders or people who are fat and just want to live their lives. 
Diet advice is everywhere. TV. Billboards. Gyms are running their promotions. “Keep your weight loss New Year’s Resolutions” are being shoved down our throats from every angle. Additionally, people who usually have other interests are suddenly all about fitness for a few weeks. It can be really, really hard to just exist as a fat person. 
Do what you want. Diet. Gym. Whatever you’re doing, absolutely go ahead, but don’t assume that everyone can or wants to hear about it. There are tons of other people who are ALSO starting to diet and/or exercise right now, so why not seek them out?