10 doctors weighed in:
What are the physiological determinants of gynecomastia?
10 doctors weighed in

Dr. Vered Lewy-Weiss
Pediatrics - Endocrinology
6 doctors agree
In brief: Hormones and fat
In men and boys mammary tissue development occurs when (t) testosterone:(e) estrogen ratio is lower. Most boys get it early in puberty; goes away as t levels go up thru pubertal progression & ratio increases.
Obesity exacerbates the problem because fatty tissue makes more e, which lowers the ratio despite pubertal progression. Certain meds like Aldactone (spironolactone) can cause gynecomastia by blocking t.

In brief: Hormones and fat
In men and boys mammary tissue development occurs when (t) testosterone:(e) estrogen ratio is lower. Most boys get it early in puberty; goes away as t levels go up thru pubertal progression & ratio increases.
Obesity exacerbates the problem because fatty tissue makes more e, which lowers the ratio despite pubertal progression. Certain meds like Aldactone (spironolactone) can cause gynecomastia by blocking t.
Dr. Vered Lewy-Weiss
Dr. Vered Lewy-Weiss
Thank
Dr. Sharon Ann Clark
Surgery - Plastics
3 doctors agree
In brief: Hormones, tissue
Gynecomastia can result from abnormal stimulation from elevated hormones, a fact that means an endocrine work-up is indicated.
The breast tissue is composed of fat and gland tissue so that heavier men can even develop pendulous breasts. Fat also leads to higher estrogen levels which stimulate the breasts. Some develop gynecomastia on only one side. Teen hormonal breast changes can improve.

In brief: Hormones, tissue
Gynecomastia can result from abnormal stimulation from elevated hormones, a fact that means an endocrine work-up is indicated.
The breast tissue is composed of fat and gland tissue so that heavier men can even develop pendulous breasts. Fat also leads to higher estrogen levels which stimulate the breasts. Some develop gynecomastia on only one side. Teen hormonal breast changes can improve.
Dr. Sharon Ann Clark
Dr. Sharon Ann Clark
Thank
Dr. Tom Pousti
Surgery - Plastics
2 doctors agree
In brief: Varies...
Gynecomastia comes from the greek meaning "gyne" meaning woman and  "mastos"  meaning breasts.
 it refers to abnormal development of large mammary glands in males. Although there may be many “causes”, most cases are idiopathic (no specific cause). The use of certain medications, drugs, organ dysfunction (kidney or liver), hormonal imbalances etc. May also be causative.

In brief: Varies...
Gynecomastia comes from the greek meaning "gyne" meaning woman and  "mastos"  meaning breasts.
 it refers to abnormal development of large mammary glands in males. Although there may be many “causes”, most cases are idiopathic (no specific cause). The use of certain medications, drugs, organ dysfunction (kidney or liver), hormonal imbalances etc. May also be causative.
Dr. Tom Pousti
Dr. Tom Pousti
Thank
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