5 year old losing weight??

my 5 year old son is suddenly losing weight.  about 1 or 2 months ago he was at the doctors and weighed 48 lbs.  he is about 45 inches tall.  I would say in the last couple of weeks, i kept looking at him (along with my husband and mother) thinking that he just looked really skinny.  he has always been thin but lately he looks really worn down and almost sickly skinny.  in my opinion, his eating habits haven't changed.  he has never been the greatest eater in the world but i really don't see any difference in his eating habits.  he has had a couple bouts of strep throat this year but other than that, he hasn't really been too sick.  he complains of leg pains occasionally, usually in his knees or shins.  i weighed him today and he is down to 44lbs.  it seems like he is losing weight for no apparent reason and that worries me.  any suggestions?

[Renee Radenberg]

I suggest you bring him to his MD and have him checked out, get blood work done and see why he is losing weight. He should not be losing weight if his eating habits have not changed. In the meantime, I recommend you give him a daily children chewable multi-vitamin and make some high calorie milkshakes (1-2 times a day) for him. You can use Carnation Instant Breakfast or use just milk and ice cream with some fruit and blend in a blender. It will give him extra protein and carbohydrates.