Reduce body fat through a calorie-controlled diet
Do regular strength training and cardio
Avoid anabolic steroids and prohormones
Limit alcohol intake
Avoid recreational drugs, especially cannabis and opioids
Review medications with a doctor if gynecomastia started after a new prescription
Eat a balanced diet with enough protein, healthy fats, and micronutrients
Sleep 7 to 9 hours per night
Manage stress
Avoid excess soy or phytoestrogen supplements if they seem to worsen symptoms
Stop using products or supplements that may affect hormones
Maintain good posture and chest muscle development
Give it time if it is recent and related to puberty
See a doctor if the lump is painful, growing, one-sided, hard, or persistent