You can stay on the Keto diet indefinitely, do it as a weight-loss plan over a single short period or cycle in and out. Fat-rich foods are key, protein is moderate and carbs are the bad guys. As the diet moves into the second and third weeks, you’ll begin to feel better. Soon, low-carb, high-fat eating will seem more natural as it becomes a habit. By week four, you can expect weight loss, especially if you’ve been physically active while sticking closely to the plan. Selecting the right food will be easier as you become accustomed to the Keto approach. Instead of lean meats, you’ll focus on skin-on poultry, fattier parts like chicken thighs, rib-eye steaks, grass-fed ground beef, fattier fish like salmon, beef brisket or pork shoulder, and bacon. Leafy greens such as spinach, kale and lettuce, along with broccoli, cauliflower and cucumbers, make healthy vegetable choices (but you’ll avoid starchy root foods like carrots, potatoes, turnips and parsnips). You can work in less-familiar veggies such as kohlrabi or daikon.