Why do people find fatty or sugary foods comforting? I mean, what is it in these types of foods that causes the body / mind to see this type of food as comforting or pleasurable? Surely from the point of view of the body, it prefers foods that are high in nutrients — so why do people who turn to food for comfort always turn to fatty or sugary foods that don't offer the body anything? just wondering??? and I hope that made sense because I'm sorry it's quite badly worded!

In attempting to preserve lean body mass, what is the relationship of body composition to caloric need: Is it true that no matter how lean a person is, the same amount of calories is needed to preserve lean body mass or the leaner a person is, the more calories are needed to preserve lean body mass? Which one is true? And thank you.

Why is margarine better than butter when margarine is just oil that is hydrogenated, which means that extra hydrogen atoms are added to oil (liquid) to make it firm? If oil is hydrogenated into butter, there would be no difference between butter and margarine because they would both be saturated fats with single bonds and the same number of hydrogen atoms. Is margarine really better than butter?

1) When I do a 3-mile or 5-mile run, I run for time and try to finish with nothing in the tank. The closer I get to the end, the more I push myself, because I know I don't need to sustain the effort much longer. When I stop running, I suddenly get very light-headed and dizzy. It never happens while I'm running. I walk briskly while I'm warming down, but that doesn't prevent it. Why does this happen? Is it dangerous?

2)  Sometimes after jogging a while, or cycling a great distance, my head begins to spin and I feel as if I'm going to pass out. Is it normal to have feelings like these, and if so, how intense should these feelings be?

How can you tell when you're full? I am not over-weight, but I tend to over-eat. How can I know when to stop?