L.K.
While I have the utmost respect for Dr. Campbell and his research. I have taken a class with him personally, and others who believe in the benefits of a vegan diet. But I personally don't believe everyone will do well on the diet. I have tried. I felt, sick, weak, had headaches, stomach aches, just over all did not feel well at all. When I talked to someone (not Dr. Campbell) about my symptoms, I was pretty much told I wasn't trying hard enough. I have found that scheduling snacks with my meals, that include proteins of greek yogurt with sliced almonds and lean animal protein, along with vegetables, fruits and whole grains, I feel much better than what I did on the China Study diet.
You can do reading and research to support anything you believe. And like I said, I do have respect for him. But my reading, research and personal experience leads me to believe that for my body chemistry, it is not the best diet. You can also read about the Inuit Indians who essentially live on whale fat and animal protein and they don't have the same diseases we do. I believe that it is our processed diet of food like products. We should get back to basics and eat food closest to it's natural state as possible.
As for your husband and your reasons, I will tell you that ANY diet improvement will lead to feeling better. You can eat plant based, not give up animal protein, and feel better. But the key is fresh, whole, preferably organic, vegetables and fruit should be the main part of the diet and the animal protein the side dish. I have proven in my family, (husband and son included) that we each do not have to have our own steak. I can fix a decent sized, lean steak, slice it before serving and still have leftovers from a family of 4. But I also will fix 2 different vegetables, maybe a side salad and some sort of fruit. The meat is the side dish. We eat a lot of chicken and fish as well, with the same formula, the protein is the side dish. I also try to cook from scratch, and limit processed foods as much as possible. Processed foods are usually full of chemicals, from artificial colors to flavors to flavor enhancers to preservatives, which is playing havoc with our health.
Now having said all of that, because I do try to eat fairly healthy, I don't feel good when I eat some sort of junk food or fast food. But it's not the animal protein it's the processed junk.
Good Luck