Today my wife and I got into a little discussion on calorie intake and weight gain. A dietitian will tell you that if you take in an extra 3500 calories a day in your food, you will gain an extra 1lb if you do not burn off that 3500 calories. This is usually true, since there is no food out there that I am aware of that weighs less than 1lb and has the normal 2500 calories required a day plus the extra 3500 calories. 6,000 calories total. My wife was trying to explain to me that you can technically eat a small pill that contains 6,000 calories and gain 1lb after your body burns off the normal daily 2500 calories required by most humans. Even if the pill weighs only several grams. I was trying to explain that this is only true if you take in that 1lb through food or water which your body then turns into stored fat. She was also explaining an example of her friend's mother who had lupus and would gain 60lbs of water weight in a day and a half. I told her "She would have had to have taken in 60lbs of water for that to happen" and my wife insisted that she didn't, that the disease magically manifested 60lbs of matter from thin air. Now I know that matter cannot be created or destroyed under normal circumstances like metabolising food. Since she will not ever believe me, I was hoping someone out there with a strong physics background could shed some proof onto this subject. Unless humans have some special ability to absorb matter from the surrounding atmosphere around us then this would be impossible, right?