Why is type 2 diabetes showing up in younger people and even teenagers now?

It's generally understood as a combination of factors rather than one single cause: rising rates of childhood and adolescent obesity, more sedentary lifestyles, changes in diet patterns, and possibly increased screening catching cases that used to go undiagnosed longer. Genetics and family history still play a role too. A teenager with strong family history combined with other risk factors is at meaningfully higher risk than general population statistics alone would suggest. References: https://obesitycanada.ca/healthcare-professionals/adult-clinical-practice-guideline/ https://guidelines.diabetes.ca/GuideLines/media/Docs/Quick%20Reference%20Guide/2024-CPG-Quick-Reference-Guide.pdf