• According to what we have found on the Internet, if you consume more calories than your body needs, you will gain weight. We calculated that Doris’s changed diet, which includes upsized meals from McDonald’s, increases her calorie consumption to more than that of what she needs.  
• If Doris consumed an upsized meal from McDonald's everyday and also have the same two meals of her old diet, she will gain a total of 17215 calories per week. For example, she has McDonald for lunch but still has the same breakfast and dinner she used to have.
• A McSpicy Single (Whole Muscle), an upsized french fries (Large), an upsized Coke (Large, 32Oz) will cause her to consume 1336 calories.
• A McChicken, an upsized french fries (Large), an upsized coke (Large, 32Oz) will cause her to consume 1146 calories.
• A Fillet-O-Fish, an upsized french fries (Large), an upsized coke (Large, 32Oz) will cause her to consume 1102 calories.
• A Big Mac, an upsized french fries (Large), an upsized coke (Large, 32Oz) will cause her to consume 1273 calories.
• A Quarter-pounder with Cheese, an upsized french fries (Large), an upsized coke (Large, 32Oz) will cause her to consume 1259 calories.
• A cheeseburger, an upsized french fries (Large), an upsized coke (Large, 32Oz) will cause her to consume 1049 calories
• A hamburger, an upsized french fries (Large), an upsized coke (Large, 32Oz) will cause her to consume 1000 calories.
• Doris burnt 1800 calories from her netball training every week and took in another 10850 calories for her other meals in a week, thus, her calories intake during the two months will be 137720. The total calories she will need in that two months would be 129808. That is going to cause her weight to increase after two months, as the amount of calories she consumed is more than that of what she needs. This effect would carry on and on as we assumed that her activity factor would not change so she still burns the same amount of calories and her calorie intake remains the same.