the ratio kilos height/weight has to do with sceleton mass too.so she may be underweight and may not.her stance about food and water and brushing teeth show whe has a little pathological issue with her health.she probably reads a lot about heathy nutrition and now she may be overdoing it.but unless she starts looking very skinny shes probably doing the right thing which says that if u are a female of 160 cm height then u should be 50-55 kg.its a ratio between 20 and 25 where the best thing is 22,5 but then again it has to dowith bones weight.
watsh her if she starts looking skinny.but even 20 kilos down of yr height over 100 is ok and makes u live longer.this 20 is for men and for women would be 15.example is male of 180 height.he is ok on only 60 kg if his bones are slight. or female of 160 hight.she is ok with only 45 kg if her bones are loght and small.and it has to do with muscle mass to in both sexes.its only fat unders skin thats bad.this fat is measured on the side of the back over ribs.u take in ur finger a portion of skin so that it doubles.and then devide the width of it by two.the number is yr fat layer there.when one is not fat at all it is lower that one cm.anything over i sm fat there over ribs on the sides of our back bone is fat...so this is how u can tell if yr friend is skinny.measuring hre double folded skin there on in front under her breasts on the sides where u can take teh skin between two fingers.i hope u know what i mean.in young people ration kolos heitht/weight usually shows whether one is too slim or normal or fat this ratio being number 20 20 25.but when we get muc older then we loose muscle and not fat so the right ratio does not mean the person is not fat.it may be 160/55 and i still have in my 55 kilos fat layers on my back and it does not show in my weight of only 55 kg cos i lost a lot of my muscles.but this is not yr problem yet...
