Environmental Health News

What's Working

  • Garden Mosaics projects promote science education while connecting young and old people as they work together in local gardens.
  • Hope Meadows is a planned inter-generational community containing foster and adoptive parents, children, and senior citizens
  • In August 2002, the Los Angeles Unified School District (LAUSD) Board voted to ban soft drinks from all of the district’s schools

#681 - TV Viewed as a Public Health Threat, 05-Jan-2000

1999 Wrap-Up, Part 2

During 1999 the American Academy of Pediatrics recommended that
children younger than 2 should not be allowed to watch television
for fear that it will stunt the development of their brains.[1]
The intellectual and emotional development of young children
depends upon interaction with adults, and children watching TV
are unlikely to receive the active attention they need from
adults, the Academy said.

Specifically, the Academy said, "Pediatricians should urge
parents to avoid television viewing for children under the age of
2 years. Although certain television programs may be promoted to
this age group, research on early brain development shows that
babies and toddlers have a critical need for direct interactions
with parents and other significant caregivers (e.g., child care
providers) for healthy brain growth and the development of
appropriate social, emotional, and cognitive skills. Therefore,
exposing such young children to television programs should be

The Academy also urged parents, once again, to limit all
children's exposure to TV to 1 to 2 hours of "quality
programming" per day. (The Academy has issued a series of similar
recommendations, based on its concern about youth violence and
TV, since 1984.) The national average for all children is now
more than 3 hours of TV per day, the Academy said.[1] In other
words, children now spend about 20% of their waking hours glued
to the tube. This does not include time spent watching movies on
videotape, watching music videos, playing computer or video
games, or surfing the internet for recreational purposes. "Time
spent with media often displaces involvement in creative, active,
or social pursuits," the Academy said. By age 70, typical
American children will have spent 7 to 10 years of their lives
watching TV, the Academy said.

The Academy published a short list of problems associated with
children watching TV:

** Children are exposed to more than 14,000 sexual references in
a year's time. If children are watching 21 hours of TV per week,
this works out to one sexual reference every 5 minutes for the
1100 hours that the average child spends glued to the tube each

** The Academy blamed TV for some of the violence exhibited by
some children. The Academy said, "More than 1000 scientific
studies and reviews conclude that significant exposure to media
violence increases the risk of aggressive behavior in certain
children and adolescents, desensitizes them to violence, and
makes them believe that the world is a 'meaner and scarier' place
than it is."[1] In a 1995 statement, the Academy pointed out that
by age 18 the average American child has viewed an estimated
200,000 acts of violence on TV alone. Video games increase that
number. "Although media violence is not the only cause of
violence in American society, it is the single most easily
remediable contributing factor," the Academy said.[2]

** An American child has viewed about 360,000 advertisements
before graduating from high school, the American Academy of
Pediatrics pointed out in 1995.[3] At that time the Academy said,
"In 1750 B.C. the Code of Hammurabi made it a crime, punishable
by death, to sell anything to a child without first obtaining a
power of attor- ney. In the 1990s, selling products to American
children has become a standard business practice." The Academy
went on to say, "The American Academy of Pediatrics believes
advertising directed toward children is inherently deceptive and
exploits children under 8 years of age" because children who are
developmentally younger than 8 "are unable to understand the
intent of advertisements and, in fact, accept advertising claims
as true."3

** But probably the most important information that the Academy
published about TV, from a public health perspective, is that
watching TV causes weight gain in children. The Academy said in
1999, "Increased television use is documented to be a significant
factor leading to obesity...."[1]

This is important for two reasons. First, excess weight is a
significant, and worsening, problem among American children.[4]
Roughly 25% of U.S. children are overweight or obese. Secondly,
children who are overweight turn into adults who tend to be
overweight as well, and the JOURNAL OF THE AMERICAN MEDICAL
ASSOCIATION said in 1999 that excessive weight gain among
American adults is an "epidemic" and a major cause of disease and

How is "overweight" defined? To find out if you are overweight,
you need to know (accurately) your height in inches and your
weight in pounds. (Most people overestimate their height and
underestimate their weight.) Now convert your weight into
kilograms by multiplying pounds times 0.45, and convert your
height into meters by multiplying inches times 0.0254. Now square
your height (in meters) by multiplying it by itself. Now divide
the resulting number into your weight in kilograms. The final
result is your Body Mass Index, or BMI. Put most simply,

A BMI of 19 to 24.9 is considered "normal." A BMI of 25 to 29.9
is considered overweight, and a BMI of 30 or above is considered
obese, according to the American Medical Association and the
World Health Organization.[6]

Among U.S. adults, the prevalence (occurrence) of obesity (BMI 30
or greater) has increased rapidly in recent years, according to a
study based on telephone interviews with more than 100,000
randomly-selected individuals each year, 1991-1998, who reported
their own height and weight. In 1991, 12% of the population was
obese; by 1998 17.9% of the population was obese.[5] And these
numbers are likely to underestimate the problem because
overweight people tend to underestimate their true weight and
everyone tends to overestimate his or her true height.

Remarkably this study showed that, from 1991 to 1998, obesity
increased in every state, in both sexes, and across all age
groups, all races, all educational levels, and among both smokers
and non-smokers. As the authors of the study said, "Rarely do
chronic conditions such as obesity spread with the speed and
dispersion characteristic of a communicable disease epidemic."[5]

A different study, in which peoples' height and weight were
actually measured, concluded that 21% of U.S. men and 27% of U.S.
women are obese. When this study considered not only obesity but
also overweight (a BMI of 25 or greater), then 63% of American
men and 55% of American women qualified in 1998, an increase of
more than 25% in the past 3 decades.[7] As noted above, at least
25% of U.S. children are overweight or obese.[8]

The BMI of 25 was not chosen arbitrarily to define "overweight."
It was chosen because that is the BMI at which weight-related
diseases start to increase among the population. As BMI increases
above 25, so do high blood pressure, type 2 diabetes, gall
bladder disease, and osteoarthritis.[7] About 80% of obese
individuals have at least one of these disease conditions, and
40% have 2 or more of these conditions.

A study published in 1999 estimated that in 1991, excess weight
killed about 280,000 Americans. That is to say, 280,000 people
who died in 1991 would not have died that year if they had not
been overweight.[9] Excess weight shortens people lives by about
1 to 3 years.[9]

The currently-accepted medical explanation for the
rapidly-increasing epidemic of obesity in the U.S. (and, indeed,
in other countries) is starkly simple: we are eating more
calories while at the same time burning fewer calories at work
and through exercise.[10,11]

However, to us the occurrence of an uncontrollable epidemic of
excess weight is somewhat perplexing in a society that is
preoccupied with body weight, fitness, and diet. Nearly one-half
of all U.S. women and one-third of all U.S. men report that they
are attempting to lose weight.[10] Health clubs and fitness
centers abound. Home exercise equipment is a booming business.
Walkers, joggers, in-line skaters and bicyclists are visible in
every city and town. Low-calorie, low-fat "health foods" are
featured in supermarkets and restaurants. Why then are Americans
of all ages, races, education levels, sexes, and geographical
locations, unable to control their weight?

A hypothesis worth considering has to do with hormones. Clever
research this past decade has identified a family of hormones
that control both appetite and the way in which the body turns
food into fat.[12] One such hormone is called leptin, and leptin
injections have recently been shown to reduce weight in humans in
a dose-dependent fashion.[13] At least as interesting as leptin
is melanocyte stimulating hormone (MSH), which caused such rapid
weight loss in obese mice that it "prompted a double-take from
the surprised scientists" who conducted the experiments.[14] We
know from recent studies of wildlife, laboratory animals, and
humans that some industrial chemicals, released into the
environment, can interfere with hormones.[15] It is conceivable
that something in the environment -- something widely dispersed
-- is interfering with the hormones that control appetite and fat

But of course these hormone-disrupters would not be acting alone.
No doubt fast foods and snack foods, and the barrage of
advertisements that induce us to eat them, are having an effect
on many of us. And a sedentary lifestyle is taking its toll, too.
Just recently a study published in the JOURNAL OF THE AMERICAN
MEDICAL ASSOCIATION showed that children lost weight, and lost
inches around the midriff, if they simply watched less TV.[16]

In sum, excess weight is a major public health problem, and
television viewing is an important -- and preventable --contributing

--Peter Montague (National Writers Union, UAW Local 1981/AFL-CIO)


[1] "Media Education," PEDIATRICS Vol. 104, No. 2 (August 1999),
pgs. 341-343. Available at www.aap.org/policy/RE9911.html.

[2] "Media Violence," PEDIATRICS Vol. 95, No. 6 (June 1995), pgs.
949-951. Available at www.aap.org/policy/00830.html. And see
"Children, Adolescents, and Violence," PEDIATRICS Vol. 96, No. 4
(October 1995), pgs. 786-787. Available at www.aap.org/-
policy/9538.html And see, "The National Television Violence
Study: Key Findings and Recommendations," YOUNG CHILDREN Vol. 51,
No. 3 (March 1996), pgs. 54-55.

[3] "Children, Adolescents, and Advertising," PEDIATRICS Vol. 95,
No. 2 (February 1995), pgs. 295-297. Available at

[4] Richard P. Troiano and others, "Overweight children and
adolescents: description, epidemiology, and demographics,"
PEDIATRICS Vol. 101, No. 3 (March, 1998), pgs. 497-504. And:
Richard P. Troiano, "Overweight Prevalence and Trends for
MEDICINE Vol. 149 (October 1995), pgs. 1085-1091.

[5] Ali H. Mokdad and others, "The Spread of the Obesity Epidemic
in the United States, 1991-1998," JOURNAL OF THE AMERICAN MEDICAL
ASSOCIATION Vol. 282, No. 16 (October 27, 1999), pgs. 1519-1522.

Vol. 282, No. 16 (October 27, 1999), pg. 1596. Also available at

[7] Aviva Must and others, "The Disease Burden Associated With
ASSOCIATION Vol. 282, No. 16 (October 27, 1999), pgs. 1523-1529.

[8] James O. Hill and John C. Peters, "Environmental
Contributions to the Obesity Epidemic," SCIENCE Vol. 280 (May 29,
1998), pgs. 1371-1374.

[9] David B. Allison and others, "Annual Deaths Attributable to
Obesity in the United States," JOURNAL OF THE AMERICAN MEDICAL
ASSOCIATION," Vol. 282, No. 16 (October 27, 1999), pgs.

[10] Phil B. Fontanarosa, "Patients, Physicians, and Weight
No. 16 (October 27, 1999), pgs. 1581-1582.

[11] Jeffrey P. Koplan and William H. Dietz, "Caloric Imbalance
ASSOCIATION Vol. 282, No. 16 (October 27, 1999), pgs. 1579-1581.

[12] Jack A. Yanovski and Susan Z. Yanovski, "Recent Advances in
ASSOCIATION Vol. 282, No. 16 (October 27, 1999), pgs. 1504-1506.

[13] Steven B. Heymsfield and others, "Recombinant Leptin for
Weight Loss in Obese and Lean Adults," JOURNAL OF THE AMERICAN
MEDICAL ASSOCIATION Vol. 282, No. 16 (October 27, 1999), pgs.

[14] Joan Stephenson and others, "Knockout Science: Chubby Mice
Provide New Insights Into Obesity," reporting on L. Yaswen and
others, "Obesity in the mouse model of pro-opiomelanocortin
deficiency responds to peripheral melanocortin," NATURE MEDICINE
Vol. 5, No. 9 (September, 1999) pgs. 1066-1067, which was
commented upon in G. Barsh, "From Agouti to Pomc--100 years of
fat blonde mice," NATURE MEDICINE Vol 5, No. 9 (September, 1999),
pgs. 984-985.

[15] For example, see William R. Kelce and others, "Persistent
DDT metabolite p,p'-DDE is a potent androgen receptor
antagonist," NATURE Vol. 375 (June 15, 1995), pgs. 581-585, and
Frederick S. vom Saal and others, "Prostate enlargement in mice
due to fetal exposure to low doses of estradiol and
diethylstilbestrol and opposite effects at high doses,"
1997), pgs. 2056-2061, and Jorma Toppari and others, "Male
reproductive health and Environmental Xenoestrogens,"
1996), pgs. 741-803.

[16] Thomas N. Robinson, "Reducing Children's Television Viewing
to Prevent Obesity; A Randomized Controlled Trial," JOURNAL OF
1999), pgs. 1561-1567.

Descriptor terms: tv; obesity; overweight; weight; diabetes;
osteoarthritis; gall bladder disease; violence; children;
hormones; leptin; msh; melanocyte stimulating hormone; high blood

Error. Page cannot be displayed. Please contact your service provider for more details. (28)