hHealthy People 2010 calls for a 20 percent

improvement in the prevalence of osteoporosis

in the U.S. (U.S. Department of Health and

Human Services, 2000). A 2005 website posting

of the National Osteoporosis Foundation

(2005) indicates that osteoporosis is a major

public health threat for an estimated 44 million

Americans, or 55 percent of this country’s pop-

ulation who are 50 years of age and older.

Eighty percent of those who will be affected by

osteoporosis are women. With aging, the

impact of osteoporosis on the health of women

is huge: 30 to 50 percent of women will experi-

ence a vertebral fracture in their lifetime (Ross,

1997).

Reframing Osteoporosis

The improvement called for by Healthy People

2010 is unlikely to be realized until health care

providers and health education messages

reframe osteoporosis—it’s a disease with roots

in adolescence. In fact, osteoporosis should no

longer be considered solely a geriatric disease

(Schettler & Gustafson, 2004). Bone is living

tissue in which there is a dynamic process of

building up and breaking down. An important

determinant of lifetime risk of osteoporosis is

bone mineral density (BMD). The optimal

building of bone requires calcium, magnesium,

phosphorus, vitamin D and protein; it’s stimu-

lated by estrogen levels and by weight-bearing

exercise. Bone formation occurs up to the age

of 30, after which a gradual loss of bone

begins. At menopause, the rate of loss increas-

es. A woman who has achieved a high-peak

BMD before the loss of bone begins is much

less likely to suffer the ultimate consequence of

bone resorbtion: fractures. Since 40 percent of

bone density accrual occurs during adoles-

cence, teenagers should be a focus for preven-

tion. In fact, suboptimal bone growth in child-

hood and adolescence is as important as bone

loss to the development of osteoporosis

(National Institutes of Health, 2000).

Numerous risk factors for osteoporosis are

unalterable:

• female gender

• increased age

Osteoporosis—it’s a

disease with roots in

adolescence

324 AWHONN Lifelines Volume 9 Issue 4

Merry-K. Moos, RN, FNP, MPH, FAAN

Had Their

Have YourTeenagers

Calcium Today?

• white race

• family history

• small frame

However, the disease can occur in all popula-

tions and at all ages (National Institutes of

Health, 2000). A history of anorexia nervosa or

bulimia and the use of corticosteroids and

anticonvulsants have been associated with an

increased likelihood of developing osteoporo-

sis. While use of alcohol and caffeine-contain-

ing beverages is inconsistently associated with

low BMD, a number of lifestyle choices includ-

ing inadequate calcium intake, low vitamin D

exposure, little weight-bearing exercise and

smoking are known to increase the risk of

developing the disease. Late menarche, early

menopause, amenorrhea and low estrogen lev-

els have been associated with diminished BMD.

Strategies for ReducingOsteoporosis in Society

Numerous strategies that have the potential to

diminish the risks of osteoporosis should be

incorporated into the routine care of all ado-

lescent females. Specific strategies that can

evolve into lifetime habits to promote wellness

include:

• Assess current calcium intake: The intake of

1,300 mg of calcium a day is recommended

for females ages 9-18. A cup of milk provides

300 mg of calcium, and 8 ounces of low fat

yogurt can have up to 450 mg of calcium.

Adolescence is the age that many young

women give up milk. In the 2003 Youth Risk

Behavior Survey only 11.2 percent of a

national sample of female students in grades

9 to 12 drank at least three glasses of milk a

day (Grunbaum et al., 2004). A study of 9th

graders found that the majority knew

calcium can prevent osteoporosis but few

knew the amount of calcium they should be

ingesting or the calcium content of common

foods sources (Harel, Riggs, Vaz, White, &

Menzies, 1998). Encourage young women to

keep a seven-day log of how much calcium

intake they are getting (make it a fun exercise

to read food labels, etc.) and to determine

their own strategies to increase their intake.

• Recommend approaches to increase calcium

intake while not encouraging excessive

calorie consumption: Young women can be

directed to resume milk consumption but

encouraged to drink low-fat or skim milk as

both have the same amount of calcium as

whole milk; calcium-fortified citrus juices are

a good source of calcium (330 mg per 8

ounces) but are high in calories.

• Recommend calcium supplements if the

young woman is unable to achieve 1,300 mg

intake most days: Calcium carbonate is the

least expensive choice with the highest

amount of elemental calcium; it needs to be

taken with food because an acidic

environment is required to maximize

absorption. Examples of calcium carbonate

are Tums® and Caltrate.® Viactiv® is another

choice, but it’s more expensive. Some people

are unable to tolerate calcium carbonate

because of gastrointestinal complaints

including gas and constipation. For these

women, calcium citrate, which can be taken

on an empty stomach, is a good choice.

Calcium citrate is more expensive and

generally contains less elemental calcium per

tablet. Citrical® is an example.

• Assess vitamin D exposure because it’s the

most important cofactor involved in calcium

absorption: In fact, in the absence of vitamin

D, less than 10 percent of dietary calcium

will be absorbed (Schettler & Gustafson,

2004). When young women stop drinking

milk, they also stop getting the benefits of

milk’s fortification with vitamin D. While

most adolescents will be able to synthesize

sufficient vitamin D by brief exposure to

sunlight, sunscreen blocks the benefit.

Therefore, given the need to educate about

the consistent use of sunscreen to decrease

skin damage, it’s probably easier to

recommend a daily multivitamin that

includes sufficient vitamin D if dietary

sources of the nutrient are insufficient. Most

multivitamins include 400 IU, which is

considered adequate.

• Assess the level of physical activity:

Adolescents involved in jumping and weight-

bearing exercise may increase BMD by 5 to

10 percent (Schettler & Gustafson, 2004).

• Discourage smoking.

• Assess for primary and secondary

amenorrhea: Amenorrhea and low estrogen

levels may be a growing risk for low BMD for

In the absence of

Vitamin D, less than

10 percent of dietary

calcium will be

absorbed

August | September 2005 AWHONN Lifelines 325

326 AWHONN Lifelines Volume 9 Issue 4

adolescents because of their contraceptive

choices.

Depo-Provera Warning

In late 2004, the federal Food and Drug

Administration (FDA) announced a Black Box

Warning concerning long-term use of depot

medroxyprogesterone acetate (DMPA, depo-

provera) contraceptive injections

(http://www.fda.gov/bbs/topics/ANSWERS/

2004/ANS01325.html, accessed April 15, 2005).

According to the FDA, Black Box Warnings are

designed to highlight special problems, partic-

ularly those that are serious, and to give health

care professionals a clear understanding of a

potential medical complication associated with

a drug. The warning was issued because

women who use depo-provera for contracep-

tion have been demonstrated in studies to lose

significant bone mineral density, with loss

being greater with increasing duration of use.

Because it’s unknown whether the loss is com-

pletely reversible with discontinuation of the

drug, the warning indicates that depo-provera

contraceptive injection should not be used as a

method of birth control for more than two

years unless other methods are inadequate to

the contraceptive needs of the patient. DMPA

results in low estrodiol levels, which may

explain the associated bone loss.

Approximately 10 percent of adolescents

choose DMPA for contraception because of its

convenience (Piccinino & Mosher, 1998).

Because they have not yet met their peak BMD,

the drug may particularly disadvantage adoles-

cents. Accumulating evidence suggests that

recovery in bone mass occurs with discontinu-

ation, but the impact over a lifetime has not yet

been assessed. Care should be taken in pre-

scribing long-term use of DMPA for adoles-

cents by weighing the risk of unintended preg-

nancy against the lifetime risk of transient low

BMD.

As newer options and formulations of con-

traception become available, we need to be

watchful of the research to determine if there

are unintended consequences relative to life-

time risks. For instance, a recent paper found

that oral contraceptives with 20 mcg of ethinyl

estradiol may provide insufficient estrogen for

optimal bone mass acquisition (Cromer et al.,

2004). As nurses committed to the health of

women and children, the best defense our

young patients may have against osteoporosis

is for us to reframe our thinking. We need to

recognize that prevention activities must start

in the early teen years and become habits for a

lifetime, we need to provide young women

with practical and attainable suggestions for

reducing their risks, and we need to commit

ourselves to monitoring the research so that we

can turn research into evidence-based

practice.

References

Cromer, B. A., Stager, M., Bonny, A., Lazebnik,R., Rome, E., Ziegler, J., et al. (2004).Depot medroxyprogesterone acetate, oralcontraceptives and bone mineral densityin a cohort of adolescent girls. Journal ofAdolescent Health, 35, 434-441.

Grunbaum, J. A., Kann, L., Kinchen, S., Ross, J.,Hawkins, J., Lowry, R., et al. (2004).Youth risk behavior surveillance—U.S.,2003. Morbidity and Mortality WeeklyReport, 53(SS-2), 1-96.

Harel, Z., Riggs, S., Vaz, R., White, L., &Menzies, G. (1998). Adolescents and cal-cium: What they do and do not knowand how much they consume. Journal ofAdolescent Health, 22, 255-258.

National Institutes of Health. (2000).Osteoporosis prevention, diagnosis, andtherapy. NIH Consensus Statement, 17,1-45.

National Osteoporosis Foundation. (2005).Disease facts. Retrieved June 13, 2005,from http://www.nof.org/ osteoporosis/diseasefacts/htm.

Piccinino, L. J., & Mosher, W. D. (1998). Trendsin contraceptive use in the U.S.: 1982-1995. Family Planning Perspectives, 30, 4-10, 46.

Ross, P. D. (1997). Clinical consequences ofvertebral fractures. American Journal ofMedicine, 103, 30S-43S.

Schettler, A. E., & Gustafson, E. M. (2004).Osteoprosois prevention starts in adoles-cence. Journal of the American Academyof Nurse Practitioners, 16, 274-282.

U.S. Department of Health and HumanServices. (2000). HealthyPeople 2010.McLean, VA: International Medical.

Merry-K. Moos, RN,

FNP, MPH, FAAN, is a

professor in the

Department of

Obstetrics and

Gynecology at the

University of North

Carolina at Chapel

Hill. She is also a

member of the

AWHONN Lifelines

Editorial Advisory

Board.