In span of 1 year, I have lost about 34 kgs. Yet, sometimes I lightheaded and dizzy suddenly. This generally happens upon sudden movement. For example while sitting up from lying or getting on foot from sitting. My entire body feels numb at this point. I feel as if time has slowed down. I got a full body checkup no more than a month ago. The results exhibited a few things amiss but I consulted a local family relative who is a doctor and not a proper GP. What should I do? Is this problem worrisome?