Unfortunately, high-carb foods like popcorn or oatmeal probably won’t fit in the keto diet. One cup of air-popped popcorn contains 5 g of net carbs, which may be ¼ of your carb allotment for the entire day. It’s also worth mentioning that one cup of popcorn is not a large serving; it contains just 30 calories and no fat, so it won’t be filling. Oatmeal likely doesn’t fit, either. About ¼ cup of plain dried oats (about ½ cup cooked) has 12 grams of net carbohydrates for 77 calories and just one gram of fat.
As for yogurt, it depends on what type you choose and whether it’s keto-compliant. About half of a 7 oz container of Fage plain 5 percent milkfat Greek yogurt, for instance, contains 3 g of carbohydrates. Remember to choose plain versions, as flavored will add more sugar (and, therefore, carbs).
Better keto-compliant snacks include nuts (1 oz almonds has 3 g net carbs), seeds (½ cup of sunflower seed kernels has 3 g of net carbs), and small amounts of low-carb fruits like berries, says Whitmire. Beef jerky and nonstarchy veggies such as broccoli and cucumbers are other good snack options on keto.