Consequently, researchers have widely discredited the hCG diet, which involves using hCG injections, pellets, sprays, or drops, and consuming as few as 500 calories daily. The diet is problematic not only because there’s a lack of research on hCG supplements, but also because the calorie requirement is dangerously low, potentially leading to nutrient deficiencies, fatigue, hormone imbalances, blood clots, and other issues. Thus, most experts agree the hCG diet is not safe for anyone, the Mayo Clinic notes. (35)
When you drink liquid carbs, like the sugar in soda, your body doesn't register them the same way as, say, a piece of bread, according to a review of studies published in Current Opinion in Clinical Nutrition & Metabolic Care. That means, even though you're taking in calories, your fullness cues aren't likely to signal that you're satisfied once you finish off a can. And that can lead to consuming more overall.
Popularized by the documentary Forks Over Knives, the Ornish diet is a low-fat, plant-based diet plan based on whole grains, vegetables, fruits, and legumes. It's based on a lacto-ovo style of vegetarianism, allowing only egg whites and nonfat dairy products. It's packed with vitamins, fiber, and lots of filling plants to keep you satiated. Some studies have shown it can reverse heart disease and have beneficial effects on other chronic health conditions. (BTW, there is a difference between a vegan diet and a plant-based diet.)