Yes, natural popcorn without seasoning or toppings is completely safe and non-toxic for cats to eat. If you look at the ingredient list of most cat foods, you’ll find that corn is a top ingredient as it’s used to bind kernels together. If your cat is eating corn in most of their food then it’s completely safe for them to eat a popped kernel of corn.
Are there any benefits
This is a topic that is wildly up for debate, but I’m of the position that if corn is found in the vast majority of cat foods then it has to have some kind of benefit to your cat. As a carbohydrate, there are definitely some benefits to cats having carbs in their diet. Your cat would have to eat a lot of popcorn in order to gain any real nutritional value but, Let’s look at the ingredients.

Protein
This is pretty self-explanatory. Your cat's diet should consist of mostly protein.
Vitamin B
B vitamins play a very important role in every cat's life. These water-soluble nutrients are essential for cell metabolism needed for proper growth, development and energy production.
Potassium
Potassium serves an important function in the conduction of electrical charges in the heart, nerves, and muscles.
Iron
This is an essential mineral in maintaining the health of your cat's body and ensuring proper blood chemistry.
Magnesium
Magnesium is an amazing nutrient for cats suffering from muscle tension, spasms or seizures. Magnesium is required for many metabolic functions, it is an activator or catalyst for more than 300 enzyme systems.
Fiber
While fiber isn’t a known nutritional requirement for cats, in the wold the fur and animal bones they would normally eat contain fiber. Fiber helps cats digestive system function properly and can prevent constipation.
How often should I feed it to my cat
If your cat enjoys popcorn, then it’s probably safe to feed it to your cat on the occasional. Your cat would have to eat a LOT of popcorn to really gain any serious nutritional value from it. Corn isn’t necessarily bad for your cat, but it doesn’t really add ay significant nutritional value to your cat's diet in the quantities that they are capable of eating.
Any concerns
The popcorn that you eat out of the microwave bag, from the movie theaters and popcorn that you get from “organic” brands, is a BAD idea to give to your cat.
Many of the sugars, salts, caramel, and seasoning that is put on popcorn that humans eat can be dangerous to your cat. It would not be wise to give your cat anything other than air-popped corn kernels that you prepared yourself.
Store-bought brands, no matter how “organic” are probably not a good idea for you to give to your cat as they can contain salt or other additives that are not intended for feline consumption.
Common Questions
Do cats like popcorn?
Cats are curious creatures and they may enjoy attempting to eat some of the foods that you eat. If they show interest, then it’s possible that your cat might like popcorn.
Can kittens eat popcorn?
Yes. Cats of all sizes and ages can eat popcorn. It is not toxic to your cat, however, this only applies to popcorn without seasoning or any additives.
Final Word
Popcorn is not really a good option for a snack. It has low nutritional value because it requires a large quantity of it to be eaten and there are many other snacks that you could give your cat that would provide more lasting value. Is it safe for your cat to eat?
Yes, but only if it’s completely plain and doesn’t have any added seasoning or ingredients. I can’t think of the last time I’ve seen popcorn that was completely plain. For that reason, I wouldn’t recommend that you give it to them on any consistent basis. Cats might enjoy playing with the kernels as they can be fun to toss around.
If that’s the case, then it’s okay to give your cat popcorn kernels to play with and if they happen to eat one, so be it!