I have a question about walking for weight loss. My walking buddy believes the theory of walking distance is what helps you lose weight best versus my theory that it is the speed at which you walk that matters. So, could you help me figure this one out? Which matters most in ultimate weight loss: speed or distance?

I am currently trying to revise my eating habits to eat less often (I'm a throughout the day snacker, and normally don't eat meals). Is it okay to replace cravings or "boredom eating" with herbal teas? I was told that tea is a no calorie drink, and yet it fills me up when I'm hungry. I have started to replace most of my cravings with tea now, so that I actually eat a lot less than before. Is tea healthy for you if it is no caffeine, herbal, and I use honey to sweeten it? I am not used to drinking much of anything in the day and am fairly slim, so could the extra water intake have any weight gaining effects on me? Could this be a healthy diet?

I have been chewing and spitting large amounts of food (pretty much always sweet stuff — pastries, chocolate, etc.) almost every night for eight or nine months. I am eating a healthy, balanced diet otherwise, maybe a little on the lower caloric side (1300 to 1500 calories per day). My chewing and spitting sessions usually follow a balanced meal. I know this is a type of eating disorder. I have done a lot of research online and I know that there are side effects, although they vary depending on who you ask. Some sites mention that chewing and spitting activates the release of insulin and results in hyperinsulinemia, insulin resistance and weight gain. Is this true? How long would it take to develop these problems? Are these reversible if I were to stop this behavior?

I have an eating disorder, and I'm now in the treatment, but it's not really a treatment. My doctor only told me that I have to gain weight every day. I'm 15, male, six feet tall, and weigh 118 pounds, and I need to get it up to 140. I don't do any exercise right now because of it, so I wanted to know how many calories should I be taking in a day. Thanx!

I've read a lot lately about midnight snacking and late night eating and obesity and calorie worries, but my problem lies in the opposite direction — I'm LOSING weight, and insatiably hungry, day and night! The only advice I get is, "Eat healthy," which is preaching to the choir, since I consume more fresh produce, mostly vegetables, and home-cook all my own meals. At a recent nutrition check-up, the nutritionist patted me on the back in congratulations for having one of the healthiest lifestyles he's seen, and shrugged at my inexplicable hunger. The fact is, I'm in the kitchen every other hour, and my body doesn't differentiate between awake and asleep anymore when it comes to hunger. I go to bed on a full stomach, and wake up every three hours to eat again. It's exhausting! I'm falling asleep during the day — but never more than an hour, because hunger strikes. And amid all this, my grocery bill climbs and my weight drops. I don't get it. What am I doing wrong?

I have recently learned that in order to burn fat as a fuel, your body requires carbohydrate. Up until this point I had been doing cardio training first thing in the morning on an empty stomach, as I had read that this is optimum for fat burning. However, now I have a small carbohydrate snack before I train in order to prevent my body using lean muscle tissue as a fuel. Today I have again read in another book that training on an empty stomach first thing in the morning burns the most fat. I am a little confused over the best thing to do! I train with weights twice a week and do cardio three times per week. I do want to maintain my lean muscle, but am looking to reduce my body fat.

How many calories does it take to lose one pound?

Does altitude affect calorie-burning? That is, if I do the exact same workout twice — once in New York City and once in Colorado — will I burn more calories at the high altitude? What things DO affect how many calories you burn in a workout?

I've heard of body suits that increase sweating during exercise. Then I heard that Saran wrap had the same effect. I want to shed pounds but first I wanted to know if wrapping plastic wrap around the stomach helps burn fat during exercise.

Do "fat burners" really work? If so, why? If not, why not?

A friend of mine and I were disagreeing about this point and I thought maybe you could help. I have heard that it is not possible to both lose fat and build muscle mass simultaneously: ideally, a person should do cardiovascular exercise with dieting to lose extra body fat, and then start to focus on building up muscle mass. He says it's possible to both burn fat and build up muscle over the same period of time. Which is the case?