Generally, foods that make you fat are those that are high in fats and contain a lot of carbohydrates. Fats accumulate in the body and resultantly you put on weight. Excess carbohydrates are stored as fats as well. Following is a list of foods that make you gain weight while minimizing their usage will definitely boost your weight loss efforts.
Milk, cheese, butter, yogurt, etc. are caloric dense and rich in fats, so try avoiding these foods as much as you can.
Cheeseburgers, fries, steaming hot pizzas and fried chicken, cheesecake, chicken nuggets, cheese sticks, burrito, tuna, may seem tempting but definitely not suitable for someone who wants to follow the 3 week diet plan to lose weight. (For more information, you can check out the 3 week diet review by Brian Flatt).
Potato fries and sweet potatoes should be avoided. Potatoes in any form are not good.
Sweetened beverages (smoothies, cold drinks etc.), sodas, sweets, white bread, white sugar, ice cream, cookies, cakes, pastries etc. These foods have less fiber in them, so they accelerate the process of digestion and are quickly converted to glucose. Insulin then, stores up some of this in the fat cells, leading to weight gain.
Hot dogs, sausages, bacon, chicken wings, hamburgers, salami, roast beef, dumplings, etc.