W

waist circumference The distance measured
around the waist. Doctors define the waist as the
imaginary line that circles the body between the
umbilicus (belly button) and the crest of the hip
bones. Healthy waist circumference is less than 35
inches for a woman and less than 40 inches for a
man, regardless of age. Waist circumference is an
important measure of health risk for conditions
such as OBESITY, INSULIN RESISTANCE, type 2 DIABETES,
and forms of CARDIOVASCULAR DISEASE(CVD) such as
HYPERTENSION(high BLOOD PRESSURE), HYPERLIPIDEMIA,
ATHEROSCLEROSIS, and CORONARY ARTERY DISEASE
(CAD). Excessive waist circumference also dramati-
cally increases risk for HEART ATTACK.
Though waist circumference alone increases
the risk for health conditions, the risk compounds
when it occurs in combination with elevated BODY
MASS INDEX (BMI). Health risk rises moderately
when BMI reaches 25 and significantly when BMI
reaches 30. In combination with waist circumfer-
ence that exceeds 35 inches for a woman or 40
inches for a man, health risk jumps to the next
level. Other risk factors for CVD, such as cigarette
smoking and physical inactivity, further increase
the likelihood for heart disease, heart attack, and
STROKE. Weight loss sufficient to decrease waist cir-
cumference also decreases BMI, improving the
health risk.

Waist circumference that exceeds 35 inches for

women or 40 inches for men when body weight is

within the range of healthy (BMI of 18.5 to 24.9)

indicates a body fat distribution pattern of ABDOMI-

NAL ADIPOSITY, which reflects increased risk for

heart attack and CVD even when no other risk

factors for heart disease are present. Doctors rec-

ommend modest weight loss (5 to 10 percent),

with emphasis on increased physical activity, to

reduce waist circumference.

See alsoHEALTH RISK FACTORS; WAIST TO HIP RATIO;

WEIGHT LOSS AND WEIGHT MANAGEMENT.

waist to hip ratio The proportion between the

distance around the waist and the distance around

the hips (WAIST CIRCUMFERENCEdivided by hip cir-

cumference). A waist to hip ratio of 0.9 in men

and 0.8 in women indicates an “apple” body

shape, which reflects an elevated body fat percent-

age, heralds an increased risk for CARDIOVASCULAR

DISEASE(CVD) and HEART ATTACKin particular. The

higher the waist to hip ratio, the greater the risk.

WAIST TO HIP RATIO AND HEALTH RISK

Health Risk Men Women

healthy, no increased risk 0.89 or less 0.79 or less

moderate to significant 0.9 or greater 0.8 or less

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WAIST CIRCUMFERENCE, BODY MASS INDEX (BMI), AND HEALTH RISK DUE TO WEIGHT

Health Risk Moderate Significant Severe
BMI overweight (25 to 29.9) X
waist > 35 inches/40 inches X
BMI overweight plus waist > 35/40 inches X
BMI OBESITYclass 1 (30 to 34.9) X
BMI obesity class 1 plus waist > 35/40 inches X