Walloon, I’m no fitness expert, doctor, or nutritionist, but based on my knowledge of the subject, I think your calorie intake is too restrictive, and your exercise program is excessive.
Your body needs a minimal amount of calories daily to function. The amount of calories your body needs depends on your gender, weight, and how physically active you are. Generally, you can figure that a moderately active person needs about 20 calories per pound of body weight per day. So a 150 pound, moderately active person would need to consume about 3000 calories per day. (See the bottom of this page for a chart.)
Eat too few calories, and your body will look to other sources of energy. Ultimately, it will begin consuming itself in order to obtain energy. To avoid this, you need to consume calories. No way around it.
I also think you’re exercising too much. Most fitness magazines will recommend a program of exercise of three to four times per day, with alternating routines (such as weight training and cardio every other day). All of the ones I’ve seen included at least one day off. This day off is important, as it allows your body time to rest and repair itself.
IMO, what you need is a little bit of moderation and flexibility. It really sounds to me like you’re trying to accomplish too much too quickly with your present routine. As effective weight loss and management involve making permanent lifestyle changes, I don’t think your program is one anyone could keep up indefinitely, or one allows for flexibility.
Instead of cutting down to 1200 calories, focus on broader, more nutritionally sound changes. Calculate what your minimum caloric intake should be. Try to consume this number of calories per day. (Though this may result in weight gain initially, if your previous caloric intake was high, eating your minimum requirement should still mean fewer calories.)
Don’t make drastic reductions to your normal diet. Doing so makes it that much harder to adopt and accept the changes, and decreases the likelihood of a permanent change. (Also, on a side note, I have read that you should not reduce your caloric intake by more than 500 calories at a time.) Keep up eating lots of fruits and vegetables, but also make sure you are getting adequate protein and fat. Keep up the vitamins, and the resolve to stay away from junk foods.
For your exercise program, I think you would be better off by 1) adding a rest day or two, 2) adding some variety, and 3) reducing the intensity. I personally would adopt a weight training routine in addition to my cardio program. Weight training will build up your muscles (it won’t immediately add bulk), and as I understand it, the more muscle you have, the more calories you burn. I would also restrict my exercising to about half an hour per day, alternate the programs, and have a day off somewhere between to let my body rest. In the future, when I feel I’m outgrowing my routine, I can accomodate either greater intensity or longer duration to my workouts.
Many people adopt programs that are drastic and potentially show results in a short amount of time. The problem is, not all these programs are healthy or sustainable. Many people also view the changes they make as temporary, and once they resume relatively normal eating, they gain weight back.
There’s a simple way around these problems. Basic psychology holds that changes that are too big or too drastic are the ones least likely to be effective or take hold. Therefore, the goal to keep in mind is to make changes that are small and incremental. They should be easy for you to adopt, and easy for you to build upon. That ease will be what will help you adopt the changes permanently.
Even if you ignore everything else I’ve written, please take the basic dieting advice: talk to your doctor before you start a fitness program.
Upon preview, I see someone’s beat me to it.