I'll chime in with some additions. Lots of good advice here, and I can't really add to it much. Personally I've made some changes myself to get healthier and have started seeing the results. I've just made some adjustments in that I don't eat any empty calories anymore. When I go to lunch I eat a healthy option, and I don't buy the chips+soda meal option, I just ask for a cup for water. I've taken some items I may have eaten at meals, and made those my between meal snacks (always healthy, like greek yogurt, protein shake or bar, sunflower seeds or nuts). For exercise, I've started some high intensity interval training just three times a week for 20-25 minutes, and then I play soccer once a week.
After 8 weeks, I've not really lost weight on the scale, but I'm tracking measurements on my arms, waist, chest and legs, and all are the same or smaller, with my waist being three inches smaller! Obviously my body is reorganising things, and I feel better. More to come, and this is a change for life.
OK, my two things to add: see a physician ASAP. He or she needs to know what you're doing and can recommend a pace of weight loss. He can also plan to do periodic blood work to make sure you are doing these properly. Consider the blood work as your oil analysis equivalent on your car. Second, find a community of people who have similar goals as you to talk with regularly. They will be your support, and you can support them. This is the mental part of it, because it will challenge you.
A great book I read on setting goals and getting the right thinking is "The SLight Edge" by Jeff Olson. A life changer.
Keep us posted and good luck!
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