Yes, they're technically a fruit, but we think olives deserve a shout-out all of their own, since they're also a great source of healthy fats and are one of a few keto-approved packaged foods. Plus, they're a great source of antioxidants, will satisfy your craving for something salty, and are blissfully low-carb. “About a palm's worth only has 3 grams of net carbs,” Sarah Jadin, RD, told Health in a previous interview.
Ketogenesis has existed as long as humans have. If you eat a very low amount of carbohydrates, you starve your brain of glucose, its main fuel source. Your body still needs fuel to function, so it taps into your reserve of ketones, which are compounds the liver creates from fat when blood insulin is low. This process is known as ketosis: It’s like when a hybrid car runs out of gas and reverts to pure electricity.
The easiest macro to calculate in the ketogenic diet is fat. Once you've got your carbs and protein set, simply fill the rest of your daily calorie needs with fat sources. If you find yourself wanting to gain a bit of weight, add approximately 500 calories, or 55 grams. If you want to lose weight, cut down on your fat intake by 200-500 calories, or 22-55 grams.