You worded your question differently, elsewhere, and I replied to that, too.
My kids are adopted, but all from ethnically high-risk groups: Chinese, South Asian, and Guatemalan.
The greatest risk is of type 2, in their case, but also, because they were adopted (this is true), they are also at greater risk of developing Type 1. An additional risk factor is that my eldest was a preemie. Added to that, she genetically appears to be Bengali Brahmin, one of the highest-risk ethnic groups.
What I am doing with them is:
Occasionally testing their blood sugars with my meter;
Making them aware of healthy diet that will not overstimulate their pancreas (low sugar, and, more importantly low starch);
Making it clear to them that the health guidelines they are taught in school and might hear from their friends are mistaken;
Making sure they get enough vitamin D from the sun (they are darker skinned, and in spite of the government guideline to USE sunscreen, we do not, and we get them out as often as possible to build up reserves and give supplemental D in winter);
I have them in swimming, at least 3 times per week, which keeps blood sugar and insulin secretion more stable, and controls their weight (all are quite slender, but, interestingly the adopted kids who develop T2 tend to be slender T2's!).
Most radical of all: I have been a vegetarian for 38 years, I still do not eat meat, but I have informed them that eating meat is healthier for them. Thus far 2 of the 3 have taken me up on it and my son really enjoys it. My daughter has eaten the breaded-and-fried fish sticks, at school (SIGH), but won't eat things like pork chops cooked in coconut oil that her dad offers.