You are allowed to bring your own food into the campus, especially since you’re a diabetic patient and concerns about not being able to eat what’s provided. This is because most campuses have rules in place that permit bringing outside food for personal consumption.
To make sure you don’t run into any issues, I recommend checking with the campus administration or facilities management team beforehand to confirm their policy on outside food brought onto premises. They may provide some guidelines or restrictions on what types of foods are permitted.
In general, it’s common sense that loose granola bars like your example would be accepted as a healthy snack for personal consumption. But it’s always best to verify with the relevant authorities so you’re aware of any specific campus rules and regulations regarding food items.
By bringinging your own snacks, not only will you have more confidence in being able to satisfy your dietary needs but also contribute minimally to waste reduction within the community.