I know it's pretty dumb, but ...

definately get vitamin D blood levels checked, so many people are deficient and it can cause fatigue and muscle aches!!! i know i experienced it and i still do in the winter months! I take prescription dose vitamin D every so often

Thyroid levels can change, so having them rechecked is a good idea.

Also, if you're on any medication for your bi-polar disorder, you may want to consider that might be what is causing it. Obviously you don't want to go off your medication without talking to your doctor, but medication can cause very serious fatigue, so please talk to your doctor about this. I went almost a decade with debilitating fatigue (sleeping 10-14 hours a day, falling asleep in really inappropriate places, feeling awful all the time) only to find out it was my medication.

As for caffeine consumption, honestly, it's not good for you, a good analogy is to think of it as getting energy on credit, you get some now, but later, you're eventually going to have to pay for it. That said, I do it when I have to in order to get through the day. I would try the no or low sugar monsters, or some other source of caffeine with fewer calories in it. Diet soda (which everyone here hates, but whatever) is an option, as is black coffee or even black tea (although caffeine content tends to be lower). I've even been known to take caffeine pills. Is it good for me long-term? No, but it can be a short-term tool. Also, for most people there are diminishing returns, eventually you may need caffeine just to feel normal, and you won't get the rush anymore, so use it sparingly.

I drink zero calorie energy drinks (monster, red bull, etc.) once in a while when I need to stay up later than usual (especially weekends) but really only when I'm doing something that's out of normal for my routine. I think if exercise on top of your typical daily activities is too difficult to imagine after a long day then an energy drink isn't going to give you the stamina you need for a good workout. I'd try maybe eating smaller meals more often so your body doesn't "crash" at any point during the day and sap your energy levels. Otherwise you'll end up dependent on energy drinks to make it through your workout days and that's really not where you want to leave yourself in the long term.

I can't comment on Monster, or thyroid or your meds, but I can tell you that for years I felt like I needed a nap as soon as I woke up in the morning. I finally went and did a sleep study and was diagnosed with severe sleep apnea. Yes I was significantly overweight and this is one of the symptoms along with loud snoring, but many skinny people have it too! Just a suggestion for one more area to consider. Using a machine at night has made such a major change in my alertness and energy during the day, along with losing the weight.

Whatever you do, be sure you do it with guidance from your medical professional and best of luck!

have you had your Vitamin D level checked? I had mine checked and it was a 7 which is critically low and that explained some of my tiredness and getting sick all the time.

I was exhausted my entire life, and trying to stay fit and healthy while being exhausted is not an easy task. I finally found out that I had a genetic mutation that wouldn't allow me to absorb vitamins. The likely hood of you having it isn't ultra common, but it could be the vitamins your taking. Even normal people have troubles digesting tablet form vitamins. Maybe try switching to powdered capsules or better yet liquid capsule supplements. They seriously changed my life. Something so small made such a HUGE impact.

You should have your iron checked. I've had issues with this in the past to the point of needing to be rushed to the ER for a blood transfusion. My symptoms were the same and could have slept my life away, day by day, and not even care. Iron supplies oxygen to your organs and most importantly to your brain. If it isn't getting enough, it will not function properly along with other organs like your lungs and heart. Please get checked.

As others have mentioned, I would suggest going to a sleep medicine doctor and have a sleep study done. If you have sleep apnea, you need to have it treated (by using a cpap machine). Sleep apnea is dangerous and has a lot of long-term health consequences. I speak from experience. I was diagnosed years ago. I was tired all the time. Some days I would go out to my car on my lunch break at work to take a nap. I just could not make it through the day. I also used to wake up with terrible headaches. Now that I use a cpap, that is all gone. Now I know the lethargy that I do have is caused from my excess weight.

I get free food being a huge temptation and something you want to take advantage of as much as possible but please DO stick to the salads (with grilled chicken for protein). Have two if you're hungry enough, just avoid the fries and buns (and desserts of course) at all costs! Make sure you're sipping that water - chugging it just makes it go through your system too fast so it's not being utilized and you're going to have to keep peeing like mad. Bring in a couple pieces of fruit for snacks.

My weekend routine used to be to get 2 cheeseburgers at the drive thru and when I started this weight loss, I cut that down to one and now I've cut them out altogether. It's not that the cheeseburger has a ton of calories, I could totally "afford" eating one for lunch but all those carbs just didn't do a thing for me. I'd much rather head home real quick to mix up some chicken salad or a ham and cheese or even some yogurt and fruit because I know they'll give me energy for a few hours, not 30 minutes.

What's wrong with daily caffeine? I don't do sugary drinks, but I sure have two cups of black coffee every day. Yum!

It is ok for a pleasure drink (1-2 a day) but not as a pick-me-up drink because positive waking up effects from caffeine on the brain disappear quickly. The lesser amount of coffee/caffeine you consume daily, the greatest the effect of caffeine will be when you really need it. At least this is my experience.