What causes gynaecomastia in men

What is Gynecomastia?

Gynecomastia is a common condition characterized by the abnormal development of breast tissue in males. It is not the same as pseudogynecomastia, which is excess fatty tissue in the chest that can occur in overweight men. Gynecomastia involves actual glandular tissue enlargement, which can sometimes be tender or painful.

What Causes Gynecomastia?

The primary cause of gynecomastia is a hormonal imbalance between androgens (like testosterone) and estrogens. While men produce small amounts of estrogen, and women produce small amounts of androgens, a shift in this balance can lead to breast tissue growth in men. This imbalance can occur for several reasons:

1. Natural Hormonal Changes

• Puberty: During adolescence, boys experience significant hormonal fluctuations. It's common for estrogen levels to temporarily rise relative to testosterone, leading to gynecomastia in about 50-60% of teenage boys. This usually resolves on its own within months or a few years.
• Infancy: Newborn boys can experience temporary breast enlargement due to the transfer of maternal estrogen across the placenta. This typically disappears within a few weeks after birth.
• Aging: As men age, particularly after 50, testosterone production often decreases, while estrogen levels may remain stable or increase slightly, leading to a relative estrogen dominance and potential gynecomastia.

2. Medications

A significant number of gynecomastia cases are linked to medications. Several drug classes can disrupt hormone balance, leading to breast tissue growth. It's estimated that medications are responsible for up to 25% of gynecomastia cases. Common culprits include:

• Anti-androgens: Used to treat prostate cancer or benign prostatic hyperplasia (e.g., spironolactone, flutamide).
• Anabolic steroids: Often misused by athletes and bodybuilders to enhance muscle mass.
• Heart medications: Such as calcium channel blockers (e.g., nifedipine, verapamil) and some antiarrhythmics.
• Gastrointestinal drugs: Including omeprazole and cimetidine.
• Antidepressants: Particularly selective serotonin reuptake inhibitors (SSRIs).
• Antiretrovirals: Used to treat HIV/AIDS.
• Chemotherapy drugs.
• Opioids.

If you suspect a medication is causing gynecomastia, it's crucial to consult your doctor before stopping or changing any prescription.

3. Medical Conditions

Certain underlying health issues can also contribute to gynecomastia by affecting hormone production or metabolism:

• Liver disease: Conditions like cirrhosis can impair the liver's ability to metabolize estrogen, leading to higher levels in the blood.
• Kidney failure: Chronic kidney disease can disrupt hormone balance.
• Testicular tumors: Cancers or tumors in the testicles can produce hormones, including estrogen.
• Thyroid problems: Both hyperthyroidism (overactive thyroid) and hypothyroidism (underactive thyroid) can sometimes lead to gynecomastia.
• Adrenal gland tumors: These can produce hormones that affect the estrogen-testosterone balance.
• Malnutrition or starvation: Periods of severe calorie restriction or rapid weight loss can alter hormone levels.
• Klinefelter syndrome: A genetic condition where males are born with an extra X chromosome (XXY), which typically leads to lower testosterone production.

4. Lifestyle Factors

• Alcohol abuse: Chronic and excessive alcohol consumption can affect liver function and hormone levels.
• Recreational drug use: Certain drugs, such as marijuana, heroin, and amphetamines, have been linked to gynecomastia.
• Herbal products: Some products containing plant-derived estrogens, like lavender oil or tea tree oil, have been anecdotally linked to gynecomastia, although scientific evidence is limited.

When to See a Doctor

While gynecomastia is often temporary and resolves on its own, especially during puberty, it's advisable to consult a doctor if:

• The breast tissue is tender, painful, or swollen.
• The enlargement occurs suddenly.
• It affects only one breast.
• You are concerned about the appearance.
• You are experiencing other symptoms like fatigue, loss of libido, or discharge from the nipple.

A doctor can help determine the underlying cause through a physical examination, blood tests (to check hormone levels, liver function, etc.), and sometimes imaging tests. Treatment depends on the cause and may involve addressing the underlying condition, adjusting medications, or, in persistent cases, surgical options.