Behind the new recommendations:
Now we need to supplement with Vitamin D?!?
By Christine Climer
In April of 2003, the American
Academy of Pediatrics issued new guidelines for preventing rickets
and vitamin D deficiency in children. Because cases of rickets
continue to be reported, the AAP recommends that all children
receive a vitamin supplement containing 200 IU of vitamin D daily,
unless they drink at least 17 ounces of either vitamin D-fortified
milk or infant formula.
These new recommendations have
caused quite a controversy, even among the medical community.
What are rickets and vitamin
D, anyway?
When skin is exposed to ultraviolet light, it makes vitamin D
from cholesterol. The active form of vitamin D is actually a hormone
that controls the absorption and metabolism of calcium and phosphorus,
so it affects how our bones are formed.
Children who do not have enough
vitamin D can experience stunted growth and skeletal deformities
such as bowed legs; this disorder is known as rickets.
But they say breast milk
doesn’t have enough Vitamin D!
Everyone knows that breast milk is the most perfect food for babies.
It contains small amounts of vitamin D because nature intended
for babies to be exposed to sunshine. Vitamin D in breast milk
is intended to supplement the vitamin D that infants make themselves
from sunshine; it is not to provide 100% of their daily requirement.
According to the Institute of Medicine, “with habitual small
doses of sunshine, breast- or formula-fed infants do not require
supplemental vitamin D.”
Babies are born with stored vitamin
D that they get from their mothers during pregnancy. These stores
are used during those first weeks of life when sunlight exposure
is often limited. A full-term infant whose mother was not vitamin
D-deficient during pregnancy should have enough stored vitamin
D to last up to 8 weeks without supplementation.
How much sunshine is enough?
The answer to this question depends on many factors. Higher levels
of ultraviolet light exist during the summer months, at lower
latitudes and when air pollution levels are low. Clothing, sunscreen
and windows block most ultraviolet light. And people with darker
skin pigmentation require greater exposure for vitamin D production
than do lighter-skinned individuals. All of these variables make
it impossible to determine a precise measurement for how long
any specific child should be exposed to sunshine in order to achieve
the daily requirement of vitamin D.
In an effort to decrease the incidence
of skin cancer, the AAP recommends that children under 6 months
old stay out of direct sunlight and that older babies and children
wear protective clothing and sunscreen when they are exposed to
sunshine. The AAP claims that initiating sunlight exposure at
an earlier age increases the risk of skin cancer. However, research
demonstrates that only episodic, high exposure sufficient to cause
sunburns increases the risk of developing skin cancer later in
life, not routine exposure of minimal duration. Further research
into sun exposure and vitamin D status in infants has been met
by stiff resistance from many doctors who feel that it is unethical
to expose children to sunshine without sunscreen.
Dr. Michael Holick, one of the
most respected vitamin D researchers in the world (professor of
Medicine, Physiology and Dermatology at Boston University School
of Medicine, and chief of Endocrinology, Metabolism and Nutrition),
believes that exposing the arms and face to sunlight for just
5 to 10 minutes two to three times a week during the summer, spring
and fall is adequate for vitamin D production and will not significantly
increase the risk of skin cancer or damage the skin. This correlates
with the recommendations of the World Health Organization and
the New Zealand Ministry of Health. A study of breast-fed infants
at 39°N latitude in Cincinnati, Ohio, demonstrated that adequate
vitamin D was made when infants wearing only a diaper were exposed
to sunshine 30 minutes a week. Babies fully clothed without a
hat required about 2 hours of sunshine each week.
How can we get vitamin
D?
Latitude and season affect the amount of ultraviolet light that
reaches the earth’s surface. During the period of “vitamin
D winter,” when sunlight exposure results in no vitamin
D production, dietary supplementation might be warranted. This
is why Sweden’s Ministry of Social Welfare recommends supplementation
for children over one year of age only from September through
April. For people living at 52°N latitude, this period extends
from October through March, and for those at 42°N latitude
from November through February. People living at 34°N effectively
make vitamin D throughout the winter.
Latitudes of selected major
cities
| Los Angeles, California |
34°N |
| Dallas, Texas |
33°N |
| Boston, Massachusetts |
42°N |
| Edmonton, Canada |
52°N |
| Santiago, Chile |
33°S |
| London, England |
51°N |
| Rome, Italy |
42°N |
| Moscow, Russia |
55°N |
| Tokyo, Japan |
36°N |
| Beijing, China |
40°N |
| Cairo, Egypt |
30°N |
| Cape Town, South Africa |
34°S |
| Sydney, Australia |
34°S |
Vitamin D can be obtained from foods many of us eat every day.
Some dairy products, margarines, orange juice and grain products
are fortified with vitamin D, but it is important to read the
label to be sure. Other good food sources include halibut, herring
and cod. The daily percentage value for vitamin D that is listed
on food labels is based on a dosage of 400 IU, so children need
only 50% of that in order to obtain the recommended amount daily.
Foods high in Vitamin D
• Cod liver oil contains about 450 IU/teaspoon. Pharmaceutical-grade
oils have been highly purified and are more concentrated than
food grade oils, so check labels for exact content.
•
3 ½ oz. salmon provides 360 IU
• 3 ½ oz. mackerel contains 345 IU
• 1 cup fortified milk or orange juice contains 100 IU
• 1 egg yolk contains 25 IU
Vitamin D supplements are available
for children. In the United States, these are available only in
multivitamins. The most common are those produced by manufacturers
of infant formulas.
Vitamins should be stored securely
out of children’s reach, to reduce the chance of accidental
overdose. Due to a built-in protection mechanism, it is impossible
to overdose on vitamin D that is made in our bodies from sunshine.
References
American Academy of Pediatrics,
“Ultraviolet Light: A Hazard to Children,” Pediatrics
1999;104(2): 328-33.
Australian Broadcasting Corporation,
“Vitamin D,” The Health Report with Norman Swan (1
November 1999). http://www.abc.net.au/rn/talks/8.30/helthrpt/stories/s63610.htm
Autier P, Dore J, “Influence
of sun exposures during childhood and during adulthood on melanoma
risk. EPIMEL and EORTC Melanoma Cooperative Group. European Organisation
for Research and Treatment of Cancer,” Int J Cancer 1998;77(4):
533-7.
Children’s Nutrition Research
Center at Baylor College of Medicine, “CNRC experts ‘D’-mystifies
nutritional rickets,” Consumer News Vol 2 (2001).
Dietary Reference Intakes for Calcium,
Phosphorus, Magnesium, Vitamin D and Fluoride (Washington, DC:
Institute of Medicine, 1999): 250-287.
Gartner L, Greer F, “Prevention
of rickets and vitamin D deficiency: new guidelines for vitamin
D intake,” Pediatrics 2003; 111: 908-10.
Good Mojab C, “Sunlight Deficiency: A Review of the Literature,”
Mothering 2003;(117):52-55, 57-63.
Gritz E, “Back to School Cancer Prevention Tips” CancerWise
(Sept 2001). http://www.cancerwise.org/september
_2001/
Holick M, “Environmental
factors that influence the cutaneous production of vitamin D,”
Am J Clin Nutr 1995;61(3 Suppl.): 638S-645S.
Kaskel P, et al., “Outdoor
activities in childhood: a protective factor for cutaneous melanoma?
Results of a case-control study in 271 matched pairs,” Br
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National Institutes of Health Clinical
Center, “Vitamin D,” Facts About Dietary Supplements.
http://www.cc.nih.gov/ccc/supplements/vitd.html
Norman A, “Vitamin D and
Milk,” University of California, Riverside, Dept of Biochemistry
& Biomedical Sciences (2000). http://vitamind.ucr.edu/milk.html
Nozza J, Rodda C, “Vitamin
D deficiency in mothers of infants with rickets,” Med J
Aust 2001;175(5): 253-5.
Scanlon K, Ed., “Vitamin
D Expert Panel Meeting October 11-12, 2001, Atlanta, Georgia,
Final Report,” Centers for Disease Control (2001). http://www.cdc.gov....pdf/Vitamin_D_Expert_Panel_Meeting.pdf
Specker B, et al., “Sunshine Exposure and Serum 25-hydroxyvitamin
D Concentration in Exclusively Breastfed Infants,” J Pediatr.
1985; 107(3):372-6.
Webb A, DeCosta B, Holick M, “Sunlight regulates the cutaneous
production of vitamin D3 by causing its photodegradation,”
J Clin Endocrinol Metab. 1989;68(5):882-7.
Webb A, Kline L, Holick M, “Influence
of season and latitude on the cutaneous synthesis of vitamin D3:
exposure to winter sunlight in Boston and Edmonton will not promote
vitamin D3 synthesis in human skin,” J Clin Endocrinol Metab.
1988;67(2):373-8.
World Health Organization, “The
Known Health Effects of UV.” http://www.who.int/uv/faq/uvhealtfac/en/print.html
Christine Climer is
a registered nurse with experience in pulmonary disease, pediatrics,
home health and hospice services. Also trained in early childhood
education, she is currently executive director and child care
nurse for an early childhood health promotion organization. She
lives with her husband and three children (including a set of
twins) in Texas and enjoys researching health issues and gardening.
