Yes, during the application process, you’ll need to declare that you have type 1 diabetes.
It’s essential to disclose diabetes (and any other pre-existing medical conditions) to your insurer during the application.
Withholding, or lying about, certain details on your life insurance application is known as ‘non-disclosure’ and this is a form of insurance fraud.
If discovered, your policy could become void and the pay out to your loved ones will be denied.