Hello i am 27, 397lb female. overall healthy besides being obese. Well since i started dieting, using slim fast and doing well on it for the past week i started feeling very dizzy accompanied with headaches i get dizzy going from sit to stand, even laying down i get a buzzed head spinning feeling. occasionally walking or standing i feel as if i am going to fall and have to lean on something. this feeling is causing me to feel nauseated. also at night only i urinate constantly anywhere from 4-7 times. which interupts with sleep. I sleep about 7 hours and feel exhausted throughout the day. I go to my pcp and all he does is give me pain meds for headaches. im really scared. I do notice if i eat something for example 1 cup of chicken fried rice along w slim fast shake after 30 min. my dizzy spells go away temporarily