The Transcendors (channeled by Rik Thurston) had said much the same thing as this Seth quote, but they also added that we’re smart to make life easy for our body and to not live on junk food or whatever.
It’s true that we create our own reality but, for most people, life isn’t supposed to be a biological stress test (unless that really is your purpose in this life).
“The ideas that you have, then, play a large role in the way the body handles its nutrients, and utilizes its health and vitality. If you believe that the body is somehow evil, you may punish it by nearly starving to death, even though your diet might be considered normal by usual standards. For it is possible for your ideas to cause chemical reactions that impede your body’s ability to accept nourishment. If you believe that the body is evil, the purest health-food diet will or may do you little good at all, while if you have a healthy desire and respect for your physical body, a diet of TV dinners, and even of fast foods, may well keep you healthy and nourished.”