In one of Andrew‘s podcast he mentions how taking melatonin supplements will make it to the body stops producing its own. Can you explain that to me?

No—Andrew does not say melatonin supplements make the body stop producing its own melatonin. The concern he raises is that supplements can add unusually high amounts of melatonin and interfere with the body’s natural pattern of release. 1

• 1. Higher-than-natural doses: The body’s own melatonin rises and falls as part of its daily and seasonal rhythms. Many supplements contain amounts far above typical natural levels, and the amount in a product may not match its label. 1 2
• 2. Timing and broader effects: Melatonin supplementation can change the total amount and normal rhythm of melatonin exposure. Melatonin also affects systems beyond sleep, including reproductive hormones; Andrew notes that melatonin has broader effects on the brain and body, including immune and cardiovascular function. 3 4
• 3. Caution and natural regulation: Andrew favors caution, particularly with routine use, and suggests behavioral approaches such as light exposure, exercise, and temperature to support or shift sleep timing. 5 6