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

I was recently turned away from a blood donation site for slightly low hemoglobin. I'm a menstruating woman and a vegetarian, so it wasn't a big shock. I'm trying to add more iron to my diet in the form of beans and cruciferous veggies and eggs (cooked on cast iron!), but I've run into some confusion. The pamphlet I got from the blood bank suggests raisin bran as a very good source of iron. Several health articles and studies I've found online also point to raisin bran, but others say that wheat bran inhibits iron absorption and should be avoided when trying to raise iron levels. Sometimes the conflicting information comes from the same source! Can you shed any light on this, Alice? Would a bowl of raisin bran a day help or hurt my iron intake?

Is it bad for you to drink hard water? Can the calcium in hard water be absorbed by your body and would this be good for you, like the calcium in milk?

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 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.

What is the difference between Ionic and colloidal in vitamins & minerals?

I sometimes can't find the time to cook for weeks at a stretch. During these periods, I live on whole grain bread, cheese, and fruits (usually pears). Oh, and a couple of soft-boiled eggs at breakfast. I feel very healthy, but my friends have told me that this diet is low in minerals. Is this true? If it is, what should I add to it?

I don't really understand the way daily vitamin supplements work... I take One a Day for Women. My question is, if the vitamins you take are not time released, does your body use them the way intended or are they just a waste of time? Thanks.