Water is the dieter's best friend. Sweet, sugary, or caffeinated drinks are the enemy of the dieter. A simple sweet "energy" or "sports" drink can be as much as 400 calories. That's a third of your total calories for the entire day. Stay away from any drink but water, with one exception.  Unsweetened green tea is acceptable to drink, on occasion. If you're sick and tired of drinking just water day in and day out, the occasional green tea is fine. Green tea has lots of antioxidants and 0 calories, which makes it fine to drink. If you're really hungry during meals, down a nice big cup of water right before you eat. This will help trick your stomach into thinking that you're more full than you actually are, making you less hungry. Simple carbs, also called refined carbohydrates, are usually not very nutritious for our bodies and get absorbed by the body very quickly. Stay away from simple, refined carbohydrates such as these while on your diet:  Cookies, candies, cakes, and other baked sweets Honey, molasses, and syrup White bread, white rice, and normal pasta Many packaged cereals Complex carbohydrates, unlike simple carbohydrates, are full of fiber as well as other nutrients, and get digested by the body and released into the blood stream far slower. Examples of complex carbs include:  Whole grain bread, whole grain pasta, brown rice Beans and legumes, such as lentils, carrots, and sweet potatoes Veggies and fruits like asparagus and apricots Go for beef that is 98% lean and only 2% fat. Go for chicken breast without the skin attached. Soy products like edamame or tofu are also high in protein, as are many types of fish, including salmon. In addition to cooking everything in trans fat, fast food burgers, fries, and shakes (or burritos, mac 'n' cheese, or sandwiches) are whoppers when it comes to salt and sugar. They are essentially empty carbs, with no real nutrients to them. If you're serious about shedding those pounds and getting your weight back on the right path, you'll stay away from fast food. Ever hear...

TL;DR in Vietnamese:
Chỉ uống nước. Loại bỏ carbohydrates đơn ra khỏi chế độ ăn. Thay thế carbohydrate đơn bằng carbohydrate phức hợp. Ăn protein gầy. Cương quyết tránh thức ăn nhanh. Buổi sáng ăn như hoàng đế, buổi trưa ăn như hoàng tử, buổi tối ăn như ăn xin. Ghi nhật ký về lượng calorie của toàn bộ thức ăn nạp vào cơ thể. Khi lỡ vi phạm (và ai cũng thế cả), bạn đừng phóng đại mọi chuyện.