Facts on File Encyclopedia of Health and Medicine

LUNGS, raising the risk for atherosclerosis and CAD
with prolonged use. As well, smokeless tobacco
contains carcinogens that release into the mouth
and is the leading cause of oral cancers. Doctors
diagnose 30,000 people with oral cancers due to
smokeless tobacco use each year in the United
States; about 8,000 Americans die each year from
such oral cancers.

CARCINOGENS IN SMOKELESS TOBACCO

acetaldehyde arsenic
benzopyrene cadmium
crotonaldehyde formaldehyde
hydrazine nitrosamine acids
polonium-210 (radon) tobacco-specific
volatile aldehydes nitrosamines (TSNAs)
volatile nitrosamines

See also CARCINOGEN; HALITOSIS; SMOKING AND
CANCER; SMOKING AND HEALTH; SMOKING CESSATION.

triceps skinfold A measure of the thickness of a
fold of SKINat the triceps (MUSCLEat the back of
the upper arm), which indicates BODY FAT PERCENT-
AGE. Triceps skinfold thickness is easy for doctors,
nutritionists, and fitness professionals to measure
as a means of monitoring loss of body fat. A ten-
sioned caliper, placed over a segment of pinched
skin at the triceps, measure the skinfold thickness
in millimeters. The thickness value corresponds
roughly to the body fat percentage. For example, a
triceps skinfold measurement of 10 millimeters
(mm) corresponds to approximately 10 percent
body fat; of 35 mm to approximately 35 percent
body fat. The triceps skinfold measurement may
also serve as an indicator for adequate nutrition in
infants and young children, with less than 5 mm

(5 percent body fat) indicating insufficient nutri-

tion.

See also BODY MASS INDEX(BMI); UPPER ARM CIR-

CUMFERENCE; WAIST CIRCUMFERENCE; WAIST TO HIP

RATIO.

upper arm circumference A measurement of

the distance around the center of the upper arm,

which serves as an approximate measure of LEAN

MUSCLE MASS. Upper arm circumference, also called

mid-upper arm circumference (MUCA), is one

method to estimate appropriate nutrition. The

muscles store protein, thus measuring the size of

muscles provides an approximation of the body’s

protein supply. In undernutrition and MALNUTRI-

TION MUSCLEsize shrinks because the body metabo-

lizes protein stores to generate energy.

Overnutrition (overweight and OBESITY) results in

exaggerated muscle size as a consequence of high

amounts of fat in the muscle fibers. RESISTANCE

EXERCISEsuch as weightlifting enlarges the upper

arm muscles, which can make upper arm meas-

urement less accurate as an assessment of lean

muscle mass.

UPPER ARM CIRCUMFERENCE AND HEALTH

Measurement Health Risk Correlation

(centimeters)

<16 MALNUTRITION

16.1 to 18.5 increased risk for undernutrition

18.6 to 22 no increased health risk

22.1 to 25 overweight, moderate health risk

> 25 OBESITY, significant health risk

See also BODY MASS INDEX (BMI); TRICEPS SKIN

FOLD; WAIST CIRCUMFERENCE; WAIST TO HIP RATIO;

WEIGHT LOSS AND WEIGHT MANAGEMENT.

upper arm circumference 307