Article continues below advertisementMeghan Trainor revealed the real reason why she began using a GLP-1.In a November 13 interview with Kayla Thomas on iHeartRadio's KIISFM, the pop star, 31, disclosed that a gestational diabetes diagnosis inspired her to start shedding pounds.Gestational diabetes is diagnosed during pregnancy when the body can't make enough insulin to support pregnancy hormones.Article continues below advertisementSource: 102.7KIISFM/YouTubeMeghan Trainor lost 60 pounds.