Despite medication, diet control, and exercise, I still have a ratio problem regarding HDL/LDL. What foods would you suggest to boost HDL, while reducing LDL?

I've been trying to diet for over two years. My goal is to lose about 25 pounds, but the most I've been able to get is 15, and I can hardly keep it off. I concentrate on eating very little and since exercise is so hard to keep up, I pretty much starve myself to death. I manage to maintain the weight for a month, and then I lose control again. I've been thinking about the various diet products in the market, such as diet teas, herbs, meal- substitution shakes, and other medical products. I'd like to know what kind of side-effects they have, and how effective they are. (Some boast a seven-day plan, but that seems hardly believable.) Also, I'd like to know how well-researched the information is on these products (i.e., are they long-term enough to cover all the side-effects?) As for aspartame, is it really harmless, or is it just not researched yet?

1) What's the deal with monosodium glutamate (MSG)? What exactly is it, and how bad is it for you really?

2) I have recently been told I have a strong intolerance to MSG. But I am having trouble in working out what it is in. Is there any chance you could give me a list of items of food in which MSG is present in? I would be extremely grateful for any help.

Can you explain the difference in healthiness of breads and grains? Are all darker grains better for you than lighter counterparts? Why? If all bread is low in fat, how can it be bad for dieters, etc.?
Thanks!

Do you recommend the natural remedy Ginkgo as a dietary supplement for good health?

Can you tell me what are the uses of artificial preservatives and additives? Also, can you tell me info on the different types of preservatives and additives and why food manufacturers use them? Can you give examples for those??

Thank you very much!!!

I wanted to know how many days of rest is recommended between workouts. I heard it was three days on to one day off...is this enough? I workout on a treadmill for 50 minutes every day and have for the last 14 months. I was not aware of how rest played a very important role until I recently read a brief article on it. I guess my question is, do I need to take that day of rest and how important is it?