Hormonal Imbalance and Breast Tissue Growth
All males produce both testosterone and small amounts of estrogen. Gynecomastia develops when the ratio shifts in favour of estrogen, stimulating breast glandular tissue to grow. This is different from pseudogynecomastia, which is simply fat accumulation in the chest area without glandular involvement.
The distinction matters because glandular tissue and fat respond to different treatments. Glandular enlargement driven by hormonal changes will not resolve through diet and exercise alone, while fat deposits may reduce with weight loss.
Puberty and Age-Related Changes
Gynecomastia is extremely common during puberty. Fluctuating hormone levels during adolescence frequently cause temporary breast tissue enlargement, affecting an estimated 50 to 70 percent of adolescent males. In most cases, the tissue regresses within one to two years without any intervention.
A second peak occurs in men over the age of 50. As testosterone production naturally declines with age, the relative influence of estrogen increases. Body composition changes, including increased fat tissue that can convert androgens to estrogen, further contribute to the imbalance.
Medications That Can Trigger Gynecomastia
A wide range of medications list gynecomastia as a potential side effect. These include certain anti-androgens used for prostate conditions, some antidepressants, anti-anxiety medications, heart medications such as digoxin and calcium channel blockers, and some antibiotics and antifungal agents.
If you suspect a medication is contributing to breast tissue enlargement, consult your doctor before making any changes. In some cases, an alternative medication may be available that does not carry the same risk.
Anabolic Steroids and Recreational Substances
Anabolic steroid use is a well-documented cause of gynecomastia. When exogenous testosterone is introduced in supraphysiological doses, the body converts some of it to estrogen through a process called aromatisation. This can stimulate breast tissue growth even in otherwise lean, muscular individuals.
Certain recreational substances, including cannabis and excessive alcohol consumption, have also been associated with gynecomastia, though the evidence is less conclusive than for steroids.
Weight Gain and Body Composition
Excess body fat plays a dual role. Fat tissue contains the enzyme aromatase, which converts testosterone to estrogen. Higher body fat levels therefore increase estrogen production, which can stimulate glandular breast tissue growth. Simultaneously, fat itself deposits in the chest area, compounding the visible enlargement.
Weight loss can reduce the fat component but may not resolve established glandular tissue. Your surgeon can assess whether glandular tissue, fat, or both are contributing to the enlargement. Understanding whether surgery could recur depends partly on identifying and managing the original cause.
When No Cause Is Found
In a significant proportion of cases, particularly in adult men, no specific cause can be identified. This is termed idiopathic gynecomastia. The condition may result from subtle variations in hormone receptor sensitivity or minor fluctuations in hormone levels that fall within normal ranges but are enough to stimulate tissue growth. Consult your surgeon for a thorough evaluation to rule out any underlying medical conditions.
