D

diabetes prevention DIABETESis emerging as one
of the most significant health concerns facing the
United States in the 21st century. Approximately
18 million Americans have diabetes and 16 mil-
lion have prediabetes, a condition of INSULIN RESIST-
ANCE that has a high risk for progressing to
diabetes. Prevention efforts target type 2 diabetes,
which primarily appears in adults as a manifesta-
tion of converging lifestyle factors. About 95 per-
cent of diabetes in the United States is type 2,
which many researchers and doctors believe
appropriate preventive measures that focus on
EATING HABITSand physical exercise can eliminate.
Type 1 diabetes, which typically features sudden
onset in childhood or ADOLESCENCE, is an autoim-
mune disorder. Most researchers do not consider
type 1 diabetes preventable through lifestyle mod-
ifications although lifestyle measures can signifi-
cantly influence insulin EFFICACY and the
development of complications related to diabetes.
The discovery of INSULINreplacement therapy in
the early 20th century provided the first viable
treatment for diabetes, which until that time had
been a diagnosis of death. Nearly 100 years later
insulin replacement therapy remains the only
treatment for type 1 diabetes. In the 1980s oral
ANTIDIABETES MEDICATIONSbecame available to treat
type 2 diabetes. Many of these medications work
by increasing cellular sensitivity to insulin. Most
type 2 diabetes develops over years to decades and
manifests after age 40 years, though doctors are
diagnosing the condition in an increasing number
of adolescents. Doctors and researchers attribute
the increase in young-onset type 2 diabetes to the
rise in OBESITYamong younger people.
Diet and exercise are the major lifestyle factors
that contribute to type 2 diabetes. Improvements
in both can delay or prevent the disease’s develop-

ment. In particular, exercise improves cell sensitiv-

ity to insulin. Numerous clinical studies have

shown that 30 minutes a day of moderate physical

activity such as walking, coupled with weight loss

of 5 to 10 percent, improves insulin resistance

more effectively than do antidiabetes medication.

Diabetes is a leading cause of CARDIOVASCULAR DIS-

EASE(CVD), KIDNEY disease, blindness, PERIPHERAL

VASCULAR DISEASE(PVD), and limb AMPUTATION.

KEY MEASURES FOR PREVENTING DIABETES

• 30 to 45 minutes of physical exercise daily


• weight loss if necessary to achieve a BODY MASS INDEX(BMI)
  below 25


• diet that features fruits, vegetables, and whole grain prod-
  ucts with fewer processed and fried foods


• annual blood GLUCOSE(sugar) test beginning at age 40 years
  (sooner in women who have had GESTATIONAL DIABETES)

See also AUTOIMMUNE DISORDERS; DIET AND CARDIO-

VASCULAR HEALTH; PHYSICAL EXERCISE AND CARDIOVAS-

CULAR HEALTH.

drinking water standards Clean water is funda-

mental to health. In 1974 the US Congress passed

into legislation the Safe Drinking Water Act

(SDWA), which the Environmental Protection

Agency (EPA) administers and enforces. Amended

in 1986 and 1996, the SDWA regulates all public

drinking water systems in the United States as

well as the sources for drinking water supplies.

Regulations define the operational parameters for

maintaining safe drinking water systems. Though

the SDWA does not apply to private wells that

serve fewer than 25 people, the US Food and Drug

Administration (FDA) encourages those who

obtain their drinking water from private wells to

maintain similar clean water standards.

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