Korean J Med.
1998 Mar;54(3):406-414.
Influence of age on serum hormone levels, visceral fat area and thigh muscle mass in healthy Korean men
- Affiliations
-
- 1Department of Internal Medicine, College of Medicine, Yonsei University, Seoul, Korea.
- 2Department of Food and Nutrition, College of Human Ecology, Yonsei University, Seoul, Korea.
Abstract
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BACKGROUND: With aging, muscle mass decreases but
fat mass increases. The purpose of this study was to
investigate the relationship of changes in body fat and
muscle mass with endocrine function.
METHODS
Fasting serum levels of hormones were
determined in 52 normal weight and 100 overweight-
obese Korean men with a wide age range(21-60yr).
Adipose tissue and muscle areas were calculated from
computed tomography scans made at two body levels,
umbilicus and mid portion of thigh.
RESULTS
Total abdominal fat areas did not vary with
aging in normal weight and overweight-obese men, while
visceral fat areas showed an increase at age 41-60,
compared with age 21-30. Thigh muscle mass and serum
testosterone levels remained relatively stable before age
40 and declined rapidly thereafter. At age 41-50, the mean
values of serum testosterone and free androgen index
were only 72% and 49% of those at age 21-30, respec
tively. The serum levels of insulin and IGF-1 declined by
20% and 33% between age 21-30 and age 51-60,
respectively. Increased visceral fat accumulation was
associated with reduced serum levels of testosterone and
IGF-1, and elevated levels of insulin. Thigh muscle mass
was positively correlated with serum levels of testos
terone, free androgen index and insulin. Fasting serum
levels of testosterone were correlated negatively with
serum insulin.
CONCLUSION
Korean men with aging showed an
increase in visceral fat and a rapid decrease in thigh
muscle mass although body weight and total abdominal
fat mass were maintained. These changes in regional
body fat and muscle mass might result from reduced
serum levels of testosterone and IGF-1.