This discussion is interesting and I learned so much that I just had to share it with all of you!
The main point that I understand now is that Dr. Fuhrman's Eat to Live recommendation of 1 cup of starchy grain, potato or squash is intended for people who want to lose weight. If weight loss is not in your plans right now, eating a nutrient rich, plant based diet with more starchy grains, potatoes and/or squashes would be fine. It's about the calorie deficit created when a person loads themselves with veggies and avoids higher calorie foods.
And, of course, the starchy plant foods are not as nutrient dense as the other plant foods like greens, so your health will ultimately benefit much more from filling your stomach with those rather than, let's say, acorn squash.
But McDougall's argument that the less starchy diet is unsustainable is a very interesting one. I really need to think about what he is saying in my own history of eating this way. I think he may have a point. I know that ideally, I would like to be able to eat as close to E2L as possible and remain at my lowest weight. But that has been impossible for me and I find myself gravitating toward eating starchy grains and squashes with every lunch and dinner. Over time, my weight has crept up a little. So this video has shed light on why this has happened to me. If I want to lose a little weight, I could go much lighter on the starches. Like that old cliche, it's not rocket science!
But it might be pointless if it's unsustainable.
What has your experience and history been with maintaining weight loss on a plant based diet?