his main crop is walnuts

For some reason, I misread this as "walrus" and was really confused, but also a bit intrigued.

I told my dad I was eating a low carb diet and his response was "but there's more calories in fat than there are in carbs." Uhm, yeah, Dad, that's why you don't eat as much of it. He's supportive but doesn't/doesn't want to understand it and makes suggestions/offerings of foods that are labeled as "healthy" (whole grains, higher carb veggies, etc.) in effort to be helpful. I appreciate the sentiment, at least. I think his idea of carbs is just sugar/sweets.

I have to be really careful about how I talk to him about anything related to blood sugar. If talking about regulating insulin can somehow be misconstrued into me being diabetic or at risk for it, etc. he goes into panic mode. My mom was diabetic (type 1) and died when I was 14 due to complications from it (it was a lot harder to manage back then). Even though the reason that I'm doing this is to avoid issues like that, it's one of his buttons and I just don't push it because it's not worth stressing him out. He sees that what I'm doing is working and that makes him happy, so he's stopped questioning it.

I wish he'd change his eating habits. He has an epic sweet tooth, but he's not overweight and 71 and stubborn.