I'm relatively new here, but not new to dieting by any means. I'm 25, starting weight about 257/currently 240/ goal 140.

I'm trying to re-lose the 50 lbs that I lost in '05, then regained over the following year and a half, plus about 50 more! I've been dieting and exercising for about 5 weeks and have lost 15-ish lbs (I'm right around 240 now)! I have felt very motivated, but I'm feeling that is starting to decrease...
My problem is for the last week-and-a-half, I have felt EXHAUSTED all the time. I'm not sure if it's because I introduced working out into my routine a couple weeks back, but I have never experienced this during prior attempts to exercise and lose weight.
Last time I lost 50 lbs, I did it by following a very low-cal diet, approximately 1200 cals per day. It came off quickly, and I still had the same level of energy than with my prior (bad) eating habits.
Does anyone have any suggestion as to why? It could just be the simple fact that I'm older now (sadly enough, I felt like I had a lot more energy when I was 23). Should I increase my caloric intake? I'm really not overdoing it at the gym - usually 30-45 minutes of cardio at 70-80%, and *sometimes* weight training. I go about 3-4 times a week.





The B vitamins work to convert food into energy.
