I'm not talking about doubts. I'm talking about a group of people who have done it for years, and at some point noticed problems. They go to the doctor and find deficiencies in their bloodwork. Then go to a nutritionist to try to correct for it. Eventually they try eating fish or something for a few days and see improvement, seemingly overnight. They then have meat meals once or twice a week, and do fine on that.

Certainly we eat far more meat than we need, and the vast majority of us should cut back. But the insistence that meat should be or even could be, entirely eliminated from everyone's diet today if we all decided to, is just wrong. But if everyone cut back, even to half, perhaps the awful industrial farming conditions could be improved. That would also take some economic policy changes to make happen, but maybe.