Baked goods. For the entire week, avoid all sweet and savory baked goods. That means not eating any cakes, cookies, cupcakes, muffins, bread, or bagels. You should also pass up salty snack foods like pretzels, baked chips, or tortilla strips. Got a sweet tooth? Opt for a single serving of fresh fruit. When you're craving something crunchy, grab some raw veggies.
High-calorie drinks. Sweetened beverages are full of calories. Drink water this week and avoid all alcohol (wine, beer, and cocktails), juice, sports drinks, sweetened teas, flavored coffee drinks, soda, and commercially flavored water (such as vitamin waters). You can also make flavored water with fresh lemon juice or other fruit if you don't like plain water. Stay hydrated, but avoid drinks that cause weight gain via empty (non-nutritive) calories.
Have a small, protein-heavy breakfast. Kickstart your day with a protein filled breakfast that will give you energy (and keep your blood sugar up) for the rest of the day. Aim for a breakfast that is 400 calories and eat it every morning at around the same time. Go for variety and rotate two to three options. Pair your breakfast with unsweetened tea or a glass of water with lemon.[6]
Trans fats, which are typically found in processed foods with partially hydrogenated oils, should be avoided when buying, cooking, or ordering food because of the role they play in weight gain. As noted in the journal Obesity, these unhealthy substances have been found to pack on the belly fat in monkeys. As it turns out, they’re not great for humans either. “Trans fats cause inflammation in the body leading to insulin resistance and impairing the body’s ability to use glucose properly, resulting in excess fat storage around the belly,” says Tina Marinaccio, MS RD CPT in 50 Ways to Shrink Your Belly. Trans fats, which are created by partially hydrogenating vegetable oils, are beloved by manufacturers because they increase the shelf life of processed foods, but they are no friend to your waistline. “Trans fats may be lurking in any processed or fried food such as chips, baked goods, and even butter spreads,”Marinaccio warns.”To avoid them, check the ingredients for hydrogenated or partially hydrogenated oils.”

Stephen Colbert may be on to something. UCLA Center for Human Nutrition researchers divided study participants into two groups, each of which were fed a nearly identical low-cal diet for 12-weeks. The only difference between the groups was what they were given to eat as an afternoon snack. One group ate 220-calories of pretzels while the other group munched on 240-calories worth of pistachios. Just four weeks into the study, the pistachio group had reduced their BMI by a point, while the pretzel-eating group stayed the same, and their cholesterol and triglyceride levels showed improvements as well.