I am 6'2" as well and I have found that 160-170 seems to be a good weight range to be in. At 140 pounds, you are at the bottom of the healthy range and 190 is the upper end. I did a check on the web and there seems to be some argument about this. The old rule was 3500 calories per pound and the new rule is somewhat higher. Assuming you are reasonably active, you would need about 2200 calories a day giving you about a 500 calorie short fall. Over a week, that would be about a pound. If you are a bit more active you could lose more, possibly between 1.5 and 2 pounds a week. Be careful not to be upset if you don't lose weight at a weigh in. Sometimes the body will replace the fat with water maintaining your weigh and latter you may drop several pounds in one week. In addition, if you drop your intake to low, your body will go into starvation mode and it will become harder to lose weight. Slow weight loss is healthier and you are more likely to keep it off than a crash diet.