Though we singled out quinoa above, whole grains in general (we’re talking cereal, rice, pasta, and more) are conducive to weight loss, especially when they’re used in place of refined—white—grains. In fact, a study published in the American Journal of Clinical Nutrition found that substituting whole grains for refined grains in the diet increases calorie loss by reducing calories retained during digestion and speeding up metabolism. Unlike refined grains, whole grains are packed with satiating, heart-healthy fiber.
When you’re eating the foods that get you there (more on that in a minute), your body can enter a state of ketosis in one to three days, she adds. During the diet, the majority of calories you consume come from fat, with a little protein and very little carbohydrates. Ketosis also happens if you eat a very low-calorie diet — think doctor-supervised, only when medically recommended diets of 600 to 800 total calories.
In the study, researchers fed mice (!) a keto diet for three days (!), and then ran a glucose tolerance test. They noticed that while the mice on a keto diet had a lower fasting blood glucose, it got higher after the glucose tolerance test and there were signs of a reduced effect of insulin compared to mice on regular mouse chow. That’s basically it.
Created in 2003 by cardiologist Arthur Agatston, this low-carb diet features three phases. The first phase is the most restrictive, limiting carbs such as potatoes and rice. Each subsequent phase becomes more lenient, and the diet emphasizes lean protein, unsaturated fats, and low-glycemic carbs such as nonstarchy vegetables. South Beach promotes lasting lifestyle changes, according to the Mayo Clinic. (21)
“A lot of people think the foundation of a paleo diet is high-fat meat, but I suggest that it’s vegetables,” says Hultin. The concept is to eat only foods — including meat, fish, poultry, eggs, fruits, and vegetables — that would have been available to our Paleolithic ancestors. This means grains, dairy, legumes, added sugar, and salt are all no-no’s.
On a ketogenic diet, your entire body switches its fuel supply to run mostly on fat, burning fat 24-7. When insulin levels become very low, fat burning can increase dramatically. It becomes easier to access your fat stores to burn them off. This is great if you’re trying to lose weight, but there are also other less obvious benefits, such as less hunger and a steady supply of energy. This may help keep you alert and focused.