My father has a strong interest in the biological side of nutrition, as do I. I remember fighting with him about coconut oil when I was home over Christmas break, as I hadn't yet gone primal but wanted to get some SFA in me after reading on here about how good they were. Now that I'm fully primal (3 weeks in and 2.6 kilos lost) he listens but still shakes his head and says "I hate meat and don't want to give up grains." He also has heart issues (arrhythmogenic right ventricular dysplasia), so I worry for him.
However, since I don't live at home, I'm trying to urge my brother (who does) to get Primal (it's helped my mood an enormous amount, and I think it would help his as well). If my brother and I are both Primal and my father sees how much it's helped us, I know he'll jump on the bandwagon. In fact, when I sent him an entire day's worth of stuff I'd eaten on Fitday with 80 grams of protein and 52 grams of carbs listed, he emailed me back with "get more protein! you should be eating 110 grams!" Not a word on the carbs. 8)
My mother still gasps when I say I cook my food in lard, though.