Diets are tricky, and never the same for two people. Generally speaking, you want to consume unprocessed foods. That means... NO sodas, fast food, cold cut deli meats, store-bought jelly, store-bought peanut butter, white bread, candy, reduced-fat milk, cheese, etc.
NO ALCOHOL, when your liver processes alcohol, it produces a substance toxic to the production of testosterone. Less testosterone ->less muscle ->more fat
Good breakfast ideas: Oatmeal (probably the best base for breakfast), fresh fruit (helps your body absorb protein), eggs (eggs are a miracle food), bacon (if you want, in small amounts)
Any other meal: unprocessed lean meats(fish, chicken, beef), fresh veggies (steamed, raw is better), brown rice (good filler to keep calories down), leafy greens (good source of calcium and help with muscle recovery), whole grains (FIBER)
There isn't any proof that GMOs are actually bad for you. GMO corn and soy aren't good for you because, well, corn and soy aren't good for you. Your body can't process corn efficiently, and soy can make you fat (mostly women, but it can effect men, too)
Protein shakes are a great way to easily add protein to your diet, and protein shakes alone will not hurt your liver. What can damage your liver is a being on a high protein diet for an extended period of time.
If you eat enough of the right foods, you will not need a multivitamin. Having a good diet isn't expensive, it's time consuming. Being lazy in the kitchen is just as bad as never exercising.
To keep the weight off, you're going to have to hit the gym, there's no way around it. You can effectively alter your metabolism by adding more lean muscle mass to your body. Muscle burns about double the energy that fat does, so weight training is absolutely necessary. Cardio is almost completely unnecessary. You want your resting heart rate to be below 70 BPM, and you want your peak rate to be above 140 BPM. Do enough cardio (30 MINUTES, MAX) to keep your heart strong. Excessive cardio burns off muscle and puts your body into sort of a limp mode, where you will burn fewer calories than weight training.
1997 TJ - Current project: Simple-ish build
1988 Civic Hatch - Runs 12's, gets 30 mpg