I very much agree that different people can respond quite differently to a diet, and sometimes you'll encounter a diet your body just can't tolerate (like atomic, I do very poorly on Atkins/low carb). However, if you find yourself feeling bad when you first start doing the LE, don't assume you won't be able to do it. Very often there is an adjustment period as your body chemistry changes in response to the diet and your body gets used to fewer meals and calories. This is completely normal and can last a few days to a week; if after a week you aren't feeling any better and cannot tolerate it, then you might consider making some changes.