Doctors at the Royal Free Hampstead NHS Trust carried out tests on 737 teenage girls and found that more than two-thirds had a deficiency of iodine, which is found in dairy products and seafood and is important for brain development.

Consultant physician Dr Mark Vanderpump, who led the research team, said: "Children used to consume a lot more milk. We found there was a lower dietary intake of milk in the diet of the girls who had the lowest urine iodine levels and this may be an important factor in why they were so iodine-deficient."

Teenage girls were focused on as they are potential mothers of the future and low iodine levels among pregnant women are seen as more dangerous because of the effect on their babies’ brain development.

http://www.cypnow.co.uk/Health/article/1067006/Doctors-issue-iodine-deficiency-warning/

I have read of similar reports of other nutritional deficiencies in teenage mothers.  Teenagers are still growing so some of the nutrients from the teen mom's diet are going to be going to the growth of her bones and tissues.  I believe bone growth is not completely done until about age 24 or so.  

Then many teens are still eating too much junk food and teenage girls are often into dieting. The worst thing that teenagers probably do to their bodies is diet sodas.  

Teen moms have a higher incidence of low birthweight babies.
 

Just to clarify, the point is that iodine is important, and milk is important. (and fish on friday won't hurt)

Teenage girls were focused on as they are potential mothers of the future

As to your point about low birth weight:

For mothers between 15 and 19, age in itself is not a risk factor, but additional risks may be associated with socioeconomic factors

http://en.wikipedia.org/wiki/Teenage_pregnancy

Quote from: ora pro me

I believe bone growth is not completely done until about age 24 or so.  
 

According to what I've read the long bones of women stop growing at 18, on average.  

I am referring to bone ossification.  I believe this would be the same thing as bone density.  

See:

http://en.wikipedia.org/wiki/Bone_growth

Timetable for human ossification
Time period   Bones affected

Third month of embryonic development Ossification in long bones beginning
Fourth month Most primary ossification centers have appeared in the diaphyses of bone.
Birth to 5 years Secondary ossification centers appear in the epiphyses
5 years to 12 years in females, 5 to 14 years in males Ossification is spreading rapidly from the ossifcation centers and various bones are becoming ossified
17 to 20 years Bone of upper limbs and scapulae becoming completely ossified
18 to 23 years Bone of the lower limbs and os coxae become completely ossified
23 to 25 years Bone of the sternum, clavicles, and vertebrae become completely ossified
By 25 years Nearly all bones are completely ossified


Kids should rarely drink soft drinks because sodas pull calcium out of the bones.  

I wish I could still grow new bone.   For me it's a matter of keeping bone.  :geezer: