24"????
that really is a bit on the skinny side. i am very surprised a doctor recommended that to you!! as the others have already said other factors are involved...usually a doctor would be focusing on your weight/BMI not merely waist size...
Weight Charts, Ideal Weight Chart, Ideal Body Weight, Ideal Weight for Height
scroll down for weight charts
BBC - Health - Healthy living
BBC NEWS | Health | Public unaware of waist size risk
i'm (almost) 5ft 4 & a medium frame (i think) my healthy recommended weight according to this chart (sometimes they vary by a few lbs) is 124 lbs to 138 lbs...yeah i'd agree with that...though before i started to put this weight on a few yrs ago i actually weighed less about 117 lbs (8 stone 4)...i stuck at that weight for 20 yrs from when i was about 16...except of course for pregnancies & the fact that in times of stress/comfort eating/man problems i would gain & lose the same 7 lbs over & over again...whenever i hit 124lbs i wouldn't go out socially again until i'd lost it!!! @ 124 lbs i felt overweight??!! jesus??! thats the point my healthy weight range actually starts!! goes without saying i must have been a bit daft at the time...i suppose things are all relative to that time/age you are/what weight you've been used to etc..i know in my 20's my concern with my weight had far more to do with what dress i wanted to get into rather than health....anyhoo...........
i know you're an inch+ taller than me but to give you an indication of how thin a 24" waist might look...if you have a peek at my pics in my profile there is a pic of me in a little dress with my sis & a friend...that dress is a UK size 10/size 6 US...as you can see i look very slim....but to be a UK size 6/US size 2 with a 24" waist i'd have to lose the equivalent of 2 dress sizes/4" from my waist from how i look in that pic!!! NO WAY!!! esp as to me now looking back i was too slim in that pic...i much prefer the 3rd pic where i'm in the black body/all in one thingy were i think i was approx a size 12/30" waist. i have no desire to be a size 10 again...i much prefer having the bigger boobs!!!
it amazes me how/why some celebs under eat to keep themselves at a size 4 UK/size 0 US?? victoria beckham/rene zellweger/nicole ritchie??? we all know that this is NOT their natural weight...we saw them before them dieted

!!! so who do they think they are fooling?? funny how differtent ppl have different ideas on what looks healthy or even sexy...
UK size 4/US size 0
30-31 inch bust, 23 inch waist and 32-33 inch hips...
personally i think a figure like that belongs on a 11/12 yr old...
yes some ppl are very petite naturally...but you can always tell the difference...those women who continually diet to look very thin have a pinched drawn look to their face...i remember in an interview courtney cox said...In Hollywood, you get your bottom half to be the right size, your face may have to be a little gaunt. You choose your battles...
oh please!!! i'd much rather have a healthy looking happy face (no wonder Posh always looks so friggin miserable...literally starving!!!) & the few extra womanly curves!!! to me women (& men!!) look far sexier with a bit of meat on their bones anyway...
plus we all need a little something to hold onto!!!

(& cuddle too of course

!!)