Juice diets do prevent your body from going into a state called ketosis, he says. Ketosis means your body has no carbohydrates to burn for energy, so it has to burn stored fat or whatever else is available, he tells WebMD. "You feel bad, even smell bad. That's what makes you feel like hell during a [water-only] fast. But is that because the toxins are coming out? No! You're going into ketosis. It's known physiology."
But the psychological or spiritual effect can't be discounted, says Dillard. "People love the idea of cleansing, of purification rituals, going to the Ganges, to the spa. It has powerful psychological, religious, spiritual meaning. That has its own positive effect on health. But we need to separate that from saying this is science or good medicine."
What is moderation? In essence, it means eating only as much food as your body needs. You should feel satisfied at the end of a meal, but not stuffed. For many of us, moderation means eating less than we do now. But it doesn’t mean eliminating the foods you love. Eating bacon for breakfast once a week, for example, could be considered moderation if you follow it with a healthy lunch and dinner—but not if you follow it with a box of donuts and a sausage pizza.
Dinner? That's miso soup with some chopped sea vegetables (like the Japanese nori, used to make sushi) snipped over top. Or you might choose a cup of brown rice with a few chopped vegetables mixed in. "Brown rice gives your body plenty of B vitamins, which is a stress reducer. It's very high fiber, will fill you up, will help you sleep, and will flush you out in the morning."