just my opinion of why...

Nuts have a high carb count. I think Dr A wanted us to learn to eat more veggies and get our carbs from them instead of from the higher count in nuts. BTW--I eat like 1/4c of nuts maybe once a week if not I would murder someone for a bag of chips, and pork rinds just don't cut it like salted nuts do. But I take a can or bag of them and measure out in ziplock baggies exactly 1/4c no more, nuts are a big trigger for some people and can't just stop at 1/4c and they eat the whole can at a time. I get 1 baggie once a week and that's it and believe me I SAVOR each and every nut!!!