This year I decided to get healthier. So far I've dropped almost 25 lbs. since January. I found this vid (below) to be interesting. I did the 2 day calorie restriction for a few weeks at the beginning. Combined this with using the My Fitness Pal app on my phone to track meals and exercise. The most interesting piece of the fitness app wasn't tracking caloric intake (although that is useful too), but seeing my nutrient intake. The key (for me, anyway) is trying to keep sodium and sugar down, and increase fiber (which is a struggle for me) and potassium. It's amazing, and kinda scary, when you realize the majority of your diet is fat, sodium, and sugar (at least mine was). Processed foods and restaruant food can be really bad (but why does it taste so good?).
It's a change, but not horrible. I started with eating more raw veggies, quickly got bored, and started looking for recipes that looked interesting, called for fresh produce (and meat in some cases), and did not call for sugar, salt, fat, etc. This helps if you like to cook and are a little adventurous. I still eat meat, but now we do more lean cuts (typically grilled) and smaller portions. I should do more fish, but holy shit salmon is expensive! So we've stuck with the Holy Trio of Beef, Pork, and Chicken.
I also started exercising more. Nothing hard core, we just try to walk or run a couple times per week, and get in some kind of strength work. Typically, we'll run 1.5 miles and walk another 3-4. Another day we just walk 5-7 miles. Usually, if we don't do the 2nd walk we'll do "circuit training" at home with dumbells followed up with some stretching.
Oh, and consult your Dr. I'm not medically trained and your current condition may not be good to jump into some of this. But
my point was, changing your diet can be done and it can be enjoyable discovering new foods. But I won't lie, craving a big bowl of ice cream while realizing it'll have 3 days worth of sugar/fat in it (and not wanting to screw the progress you've already made) is a real bitch at times.